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diff --git a/78733-0.txt b/78733-0.txt new file mode 100644 index 0000000..503ef45 --- /dev/null +++ b/78733-0.txt @@ -0,0 +1,8978 @@ +*** START OF THE PROJECT GUTENBERG EBOOK 78733 *** + + + + + THE MASTER OF DESTINY + + + + + BOOKS BY + FREDERICK TILNEY + + THE BRAIN FROM APE TO MAN + + IN COLLABORATION WITH + HENRY ALSOP RILEY + + THE FORM AND FUNCTIONS OF THE + CENTRAL NERVOUS SYSTEM + + + + + THE MASTER OF DESTINY + + A BIOGRAPHY + OF THE BRAIN + + BY FREDERICK + TILNEY, M.D. + + WITH A FOREWORD + BY AUSTEN FOX + RIGGS, M.D. + + [Illustration] + + DOUBLEDAY, DORAN & COMPANY, INC. + GARDEN CITY MCMXXX NEW YORK + + + + + [Illustration] + + COPYRIGHT, 1929, 1930 + BY FREDERICK TILNEY + ALL RIGHTS RESERVED + PRINTED IN THE UNITED STATES AT + THE COUNTRY LIFE PRESS + GARDEN CITY, N. Y. + + FIRST EDITION + + + + +FOREWORD + + +Race after race of man has appeared on this earth, lasted but a short +span of time, and then met disaster and extinction. Our modern race is +of this series. We have reason to believe that it differs in quality +from its forerunners chiefly in its cerebral endowment. That its +progress from animalhood to civilization is due to this endowment, is +not questioned, for its victory over environment, its ascendency over +all other animals is plainly due to its superior brain power. + +How did this race originate? Like all the other races preceding it? Or +by some aberrant, instantaneous freak of creation? How did it acquire +its characteristic brain? As the bird its wings, as the elephant its +trunk, as the camel its hump, or by a divine act of separate and +special creation? Those who maintain the quarrel over man’s origin are +not those who have familiarized themselves with the history of the +world and its creatures; they are not the astronomers, the geologists, +the biologists, the anthropologists or the archeologists. They are +clearly those who prefer believing to thinking, the traditionalists, +good men mayhap but not necessarily wise. In the earlier days of +science (it is only four or five hundred years old), its devoted +labourers were persecuted by Church and State. They had to give +respectful attention to criticism or else perish by fire and sword. +But, as we have advanced slowly from religious persecution and the +auto-da-fé to mere intolerant and wordy remonstrance, the scientist +has paid but scant attention to these quarrels. He feels that as they +are not of his making, neither are they his concern. Perhaps he is +not quite right there. To be sure, he is criticized, not wisely but +too well, and for the most part not quite fairly. We have criticized +him for an assumed lack of reverence, but even more for his obvious +indifference to our criticism. This has justice in it for, though his +indifference to criticism may be excused, the ignorance upon which +this criticism is founded should be his first concern, for the man +of science is the teacher and ignorance is his very opportunity. +Heretofore, however, he has seen his opportunity too narrowly, for he +has been content to teach only the few embryo scientists apprenticed to +his own particular field. He has not, until very lately, realized that +his hard-won knowledge is far more needed and therefore far more owed +to those who are most ignorant of it, in short, to the great mass of +men and women outside the scientific world. + +“You are irreligious,” said his critics. “You have been weighed +and found wanting in that devotional attitude we find essential to +humanity. You do not even listen to our reproaches. You are irreverent!” + +For the most part, there has been no answer. The men of science have +been strangely preoccupied with their own business of finding out +all they can of their fellow man, of his nature, his origin, his +difficulties, his dangers, and of his predictable future, all in the +faith that such knowledge will ultimately benefit mankind. + +Now at length one of them has made rejoinder to these protests. +He admits that he has been preoccupied, especially so in the past +twenty years, with laborious but fascinating research into just these +questions so vitally concerning his fellow man. He admits that he had +not thought his scientific gleanings would interest any but scientists, +but he denies irreverence and insists that neither he nor any other +who spends his life in studying man and his place in nature could lack +reverence. He cannot find himself entirely in accord with any of the +eleven surviving religions which guide the lives of many men to-day. +The twelve extinct religions of the past also leave him unsatisfied. +Nevertheless he worships devoutly, though in a temple transcending in +significance and beauty any wrought by the hand of man. His devotion is +no mere lip service expressive of the self-protective instinct, but one +that takes form in labour. In spite of disappointment and hardship, he +has persevered through years in that labour, with the single object of +gaining a deeper understanding of man and his place in nature. + +It is now our turn to admit error and ask if we may not share in the +fruits of his research--even though our understanding has thus far been +alien to his field of labour, even though our path has not led us to +his temple, even though we have not been aware of his devotion. We +urge him to speak to us, not as to scientists, but as to his fellow +creatures, fellow citizens and fellow sufferers. We urge him to speak +to us plainly, believing that whatsoever has value in human knowledge +may be simply told. + +With some hesitation he has consented. He has chosen to speak to us +of the brain, as the most direct approach to the comprehension of the +nature of man. He points out that this master organ of life holds the +secret of human success, that its function is human progress, its +neglect human disaster. + +The immensity of the retrospect of his story will create in us the +wholesome effect called humility. The prospect he pictures is fraught +with the terror of what may happen, but it also holds forth inspiration +to courage and is golden with hope. No man can follow this account +without being inspired by a vision of the dawning of a new era of +progress, not an era of greater possessions but of better use of those +already possessed; of better relations between peoples and races; and +being sobered by a realization that this hope lies in developing still +further the efficiency of the master organ of destiny, through training +and education. + +The scientist speaks. He tells what he has seen and heard and read +through the long pilgrimage of years, searching for the truth, and +he gives us the fruit of these labours, simply and accurately. But +scientific accuracy and matters of fact are only his raw material. They +are woven into the fabric of a true story, vibrant with adventure, +warmed by the love and reverence of the humanitarian, and illumined by +the prophetic imagination of a poet. + +This tale of man’s emergence is fascinating, inspiring, stimulating, +but when it brings us to the climax of the present it becomes a +challenge. We are faced by an awful question. Shall the glorious race +of modern man sink into oblivion, as all the preceding races have sunk, +or may he save himself from chaotic ruin? If he is to be spared for +further progress to greater heights of happiness, he must take heed +of his own history, he must value his forebrain as his master organ +and set himself diligently to develop its powers more fully than ever +before. To this end he must discard the last bit of fundamentalism, +and the false security of all superstition; he must learn to depend +courageously on his own power to understand and control himself; he +must give up superhuman sanctions for evils that his intelligence has +long since discarded. Knowledge must replace superstition--else the +embattled hosts of the world will again be at their bloody work of +extinction, praying to the same god, using the same old prayers. It is +only by increasing the scope of his forebrain through self-knowledge, +training, and education that man can save himself from the old pitfalls +from which neither the old nor the new religions have heretofore saved +him. It is only thus, through understanding, that he can ever hope +to make full use of the forces of growth and change which we call +evolution. But our scientist gives us reason to hope that through +intelligence, itself a product of evolution, man may yet not only +escape destruction by these forces but may even go far toward gaining +a mastery over them which will insure the progress of his race toward +planes of usefulness and happiness as yet undreamed of. + +It is indeed time that we think of ourselves as men in the making +and cease to consider ourselves as gods and the lords of a finished +creation. + + AUSTEN FOX RIGGS. + + Stockbridge, Massachusetts, + October, 1929. + + + + +CONTENTS + + + PAGE + + FOREWORD v + + CHAPTER + + I. PRIMITIVE ANCESTORS 1 + Origin and Early Days of the Brain + + II. ANCESTORS BEFORE THE APES 24 + The Brain from Fish to Man + + III. MAN IN THE MAKING 51 + Human Progress from Prehistoric to Modern Times + + IV. EDEN OR EVOLUTION 85 + Genesis and the Origin of Species + + V. BIRTHPLACE AND EARLY BEGINNINGS OF MAN 107 + Influences of Forest and Plain on Brain Development + + VI. DAWN OF THE PRIMATE BRAIN 129 + The Lowest of the Monkey Kind + + VII. ON THE WAY UPWARD 152 + Brains of the Old World Monkeys + + VIII. MANLIKE TENDENCIES 168 + Brains of Gibbon and Orang-Outang + + IX. HUMAN IN MINIATURE 186 + The Brain of the Chimpanzee + + X. ALMOST HUMAN 212 + The Brain of the Gorilla + + XI. HUMAN AT LAST 239 + The Brain of Prehistoric Man + + XII. IMPLEMENTS OF HUMAN SUCCESS 267 + How the Hand, Foot, and Brain Led the Way to Humanity + + XIII. ESTIMATES AND VALUES 301 + Assets and Liabilities of the Human Brain + + XIV. THE FINAL TEST OF THE BRAIN 330 + World Coöperation and Recivilization + + + + +THE MASTER OF DESTINY + + + + +CHAPTER I + +PRIMITIVE ANCESTORS + +ORIGIN AND EARLY DAYS OF THE BRAIN + + +Since every well-arranged biography should start at the beginning, we +may first inquire into the origin of the brain. The early history of +such an important organ must be closely interwoven with the genesis of +man. If man were the result of a separate creative miracle, so also was +his brain. + +But we are not obliged to accept this view which attributes the +universe and all living things to creative miracles. There is another +and equally reasonable possibility. We may, for example, assume that +man and all else came into existence by that process of continuous +change and progressive development called evolution. We have excellent +grounds for accepting such an assumption. Astronomy, geology, biology, +chemistry, and all of the sciences relating to mankind have revealed +the essential facts. Any other interpretation must disregard or +repudiate this convincing record. With such a record as this to guide +us we may turn our attention to the origin of the brain. + + +_Earliest Forms of Animal Life_ + +The inception of life on our planet was simple in the extreme. The +earliest animals, although well organized, possessed no special organs +in the strict sense. In the beginning there was nothing which could be +specifically called a stomach or a heart, a lung or a kidney. Certainly +there was nothing even remotely resembling a brain. The business of +living was transacted within a single cell. This cell was so small +that it could not be seen by the naked eye. Each of these cells was +sufficient unto itself. Each played its own separate part with a simple +programme of existence. Each was required to get its own food, to carry +on its own chemical activities of digestion and elimination. Finally, +after it had been successful in this remarkable process, it was called +upon to produce offspring, to perpetuate its species. This last act +was the crown and climax of its life, for in this way it conferred a +material immortality upon its kind. + +The amœba, among living animals, is a good example of this simple +life. It is wholly intent upon carrying on within itself the earliest +traditions of existence. All of its life is conducted within a +single microscopic cell, which is at once its office and workshop. +It has nothing in its make-up that could in the ordinary sense be +called an organ. In such amœban animals as these there seems to be +nothing progressive, nothing to suggest the possibilities of further +advancement. Each amœba might, if such a thing were possible, look back +over a long line of ancestors exactly like itself. In looking forward +it might see no great possibility of progress. Perhaps it might reach +the more specialized conditions of its present-day relatives with +contractile threads in their substance and vibrating hairs by which to +move themselves about. At best the outlook of the amœba for progress +was restricted within very narrow limits. + + +_Familiar Animals of Earliest Type_ + +Certain events in the long history of these little animals have +acquired much human interest. At times some of these simple lives +become strikingly dramatic. Their monotonous existence is changed +and they pass through certain exciting phases. Such a drama is often +enacted when certain amœbæ gain entrance into the body of another +animal and there become parasites. The other animal may be some +huge beast or even man himself. One unpretentious amœba (_Amœba +histolytica_), if it gains entrance into the intestinal tract of man, +may cause amœbic dysentery and abscess of the liver. Another single +cell animal (_Trypanosome Gambiense_) living in the blood of certain +cattle is often conveyed by the tsetse fly to human blood where it +produces the fatal disease known as “African sleeping sickness.” +This small animal claims hundreds of thousands of victims a year. In +tropical Africa its devastations go on unchecked over an area of more +than a million square miles. In this region sleeping sickness kills +as many persons as all other diseases combined. From five to seventy +per cent. of the inhabitants in different localities are stricken. +Cattle, horses, and other domestic animals cannot be kept because of +this disease. On this account, and also because the area in which +the sickness rages is extremely fertile, it has been said that the +conquering of this malignant protozoan would be equivalent to the +discovery of a new continent. + +Even better known are the several acts in the cycle of the _plasmodium +malaria_. This protozoan animal is often borne by the Anopheles +mosquito and injected into the blood of man. Then follows the familiar +series of pathological events consisting of chill, fever, and sweat, +called malaria. In certain respects it seems like retributive justice +when this animal is injected into the body of man to cure the effects +produced by another microörganism. The other organism is the spirochæte +which causes syphilis. It often produces changes which destroy the +human brain in consequence of a disease known as paresis. Many other +protozoan animals are parasites, but in the main they live and have +lived simple, unobtrusive lives. + +Notwithstanding their apparent simplicity of structure and action, +these minute animals, like all other things, have been subject to +the influence of continuous change. They have responded to this +influence in different ways. In many instances, through generations of +reproduction, they have effected combinations and recombinations of +their essential constituents out of which have emerged modifications of +their original structure. Often these changes have proved progressive +and contributed to more complex modes of living. Often they have been +regressive or non-progressive. It was the progressive modifications in +these earliest animals that were of utmost importance to the origin of +the brain. This organ was not yet in sight, but adaptations working +toward it were soon to appear. + + +_Critical Changes in Animal Existence_ + +In the course of time certain critical changes took place in the +lowly scheme of animal existence. These were distinctly progressive +changes. Some of the single-cell animals began to live in colonies. +Circumstances thus conferred upon them a community life. They began to +exist in close contact with others like themselves and were compelled +to forego their simple, independent habits. They were, in fact, +actually joined to each other by rather slender bonds of their own +vital substance--protoplasm. This was an epochal stride forward. It +was the first step which led to progress. In some instances it brought +about entirely new relations between these animals and the world in +which they lived. Now, since these small cells were grouped together as +colonies, each individual cell lost much of its own independence. Its +interests became, in some degree at least, the interests of the group. +If, as a single cell by itself, it had been thoroughly self-contained, +now it was necessary for it to follow the needs and inclinations of +its neighbours. It was forced to observe the conventions and habits +of its colony. This condition of affairs exists in what are known as +the colonized protozoans. In addition to the advantages of community +life there was another and far more important reason why this new kind +of existence was a critical step. It introduced for the first time +the principle of differentiation or class distinction. A division of +labour was thus made possible. Some of the cells in each group were +forced to take up positions on the outer surface of the colony. Others +occupied places inside of the group. This arrangement immediately +created a distinction between “outer cells” and “inner cells.” It was +destined to have far-reaching consequences because it established a +difference in the responsibilities of two great classes. The outer +cells made an immediate and direct contact with the world. They were +nearest to the water, to the light, and to all of the outer chemical +substances necessary for living. They were like guards and outposts +about a camp, defending the colony from adverse influences. They might +be likened to the first line of battle in the aggressive struggles for +life, acting as foragers and procurers of food. The rôle of the inner +cells was different. Their contacts with the world were more indirect +and established largely through the outer cells. Their offices were +especially confined to the inner workings of the colony. They became +the germ cells whose function it was to insure the immortality of the +species. This arrangement was a momentous advance in the direction of +progress. It was particularly momentous because it laid the foundations +upon which all of the great developments in the animal world were to +be built. In a certain way, it was also a prophecy, for it foretold +the coming of animals that were to follow the protozoans. These +newcomers, the metazoans (animals which came after the first forms of +animal life), were to possess a body with outer cells engaged chiefly +in the efforts of life, while the inner cells would be particularly +concerned with the essence of living, such, for example, as digestion, +assimilation, and circulation. + +This remarkable process of class distinction among cells developed new +and useful methods in living. It brought about a division of labour in +the business of life. Different parts of the animal now had different +obligations to fulfil. Some parts served to move the body about, some +were employed in digesting food, some in eliminating waste, some in +breathing and circulation, some in reproduction. In the end, this +division of labour resulted in the formation of a body made up of many +different organs, each having its own particular responsibilities. +We may find an excellent example of the very earliest stages of this +division of labour in Volvox, one of the colony-forming protozoans. +Most of the colonized cells of this minute animal are on the outside, +forming a hollow sphere. These cells are equipped with minute hairs +or flagellæ which, by their constant motion, keep the animal rolling +around in the water like a hollow rubber ball. In this manner it seeks +and finds its food, and thus also it may escape when threatened. But +all of the cells of Volvox are not on the outside. A number of them are +tucked away from the actual surface of the animal. These are the sex +cells to which is entrusted the important duty of reproduction. + + +_Early Influences at Work to Form the Brain_ + +Even by this time in the history of the earth, although animal life had +been developing for millions of years, there was no sign of anything +like a brain. The forces, however, which would eventually bring such +an organ into existence were already at work. Perhaps from this great +distance it may be difficult to recognize the exact nature of these +forces as they began to act at this particular stage of life. They were +present nevertheless, faintly discernible like the first streaks of +dawn which precede the sunrise. This figure of speech may seem to imply +that in the end the brain was the actual sun destined to rise above +the horizon of animal life and ultimately to dominate all progressive +achievement. The rest of this biography must prove whether this is an +extravagant figure or not. One important influence behind those forces +that eventually produced the brain stands out clearly. It seems to have +been the direct result of that class distinction among cells which +caused such effectual division of labour. With this subtle influence at +work it required one further critical step to set in motion the events +which were to end in the formation of a brain. This step was taken +when the sponges (_Poriphara_), the simplest of metazoan animals, came +into existence. They differed from the protozoans, even the colonized +protozoans, because their bodies were more complexly organized. +The individual cells forming them had lost most of their separate +independence. All of these cells were now incorporated in a single +living individual, and each cell was subordinate to the interests of +the whole. + +Cell distinction had become still more important because of the +increase in size of these animals. The outer cells now formed a +covering or skin called the “ectoderm.” The inner cells constituted +the wall of a cavity, which might be likened to the lining of the +stomach. The lining is called the “entoderm.” Many minute openings +or pores in the outer covering established communication by means of +small canals with the inner cavity of the animal. Through these pores +water is inhaled and carries with it particles of food into the inner +chambers. These particles are absorbed, and the water is then exhaled +through a larger opening called the “osculum.” + +It was at this critical point that a decisive factor leading to the +formation of the brain made its appearance. Some of the deep cells +around the pores and outlets of the sponge formed “muscles.” In many +respects this was a new device, and the sponges become especially +interesting because of this innovation in animal life. The innovation +itself resulted in a special machine for producing motion; namely, the +muscle cell. Such muscle cells in the sponge are extremely simple. They +form rings around the pores and the outlets which, by contracting, +regulate the flow of water through the animal. But such muscle action +as this is extremely important because if the water in the sponge +contains an abundance of food particles, muscular contraction prevents +too rapid outflow. This slowing of the ex-current stream, among other +things, allows more time for absorption and digestion. The muscles in +different parts of the sponge act independently. Each one is, so to +speak, a free agent, occupying its position at its own particular pore +or outlet. If, however, it became necessary for all of these muscles +to contract at the same instant in a concerted effort, let us say, to +make the sponge move, there would be no mechanism to assure harmony +of action. The muscle cells at each outlet would react according to +their own inclinations--some relaxing, others contracting. Confusion +of action could scarcely fail to result. The sponge, however, does +not need to move about in order to get its food. Being stationary, it +obtains its nourishment by sucking the water through its pores, and by +regulating the flow the muscle cells do all that is required of them. + + +_A New Motor Device_ + +Simple as is this muscular equipment, it possesses great possibilities +for further development. It clearly indicates how such mechanisms for +producing motion might be expanded to create all of the surprising +varieties of motors which in time enabled animals to move about over +the earth, in the water, and through the air. It is true that the +simple strands of muscle in the sponge are far from powerful; but when +a number of muscular strands are collected together they may take form +in such muscles as the biceps of the arm, the great extensors of the +leg, or those covering the entire body. + +The presence of the muscle cells created the need for a nervous +system to control and regulate their activities. In order to act +together muscles require a supervisor. The first important step in +this direction was taken when certain simple animals like hydras +and sea anemones (_Metridium_) made their appearance. These animals +are equipped with muscles in several parts of their bodies. Some of +them, unlike the sponges, have the power to move about a little, +crawling slowly like snails. They are also capable of moving their +many tentacles, and thus are able to reach out and grasp food. All of +these movements call for the action of the many different muscles. The +sea anemone has thirteen different sets of such muscles, the exact +coöperation of which requires the closest harmony of action. Each part +must be mutually adjusted to the others. It must act in the right +rhythm and with the proper force. Such delicate adjustment as this +could not be left to chance. It needed an adjuster and regulator. It +required also a system of communication between the cells in order +that each might sense how the others were acting during any given +interval of time. In consequence of these requirements many cells were +specialized as timers, signallers, and dispatchers. They acted like +independent telephone stations, each serving separate districts; such, +for example, as the individual tentacles of hydra or of sea anemones. +These separate stations were known as nerve cells. _In them the first +elements needed for the origin of the brain made their appearance._ At +first they were scattered and had limited communication by means of +slender strands, the nerve fibres. There was as yet no central operator +for receiving and routing their messages which were transmitted rather +diffusely by a loose nerve net. + + +_Foundation Stones of the Brain_ + +In spite of this apparent simplicity, these nerve cells were the +foundation stones of the brain. Scattered as they were, they lacked +that unity of action which is the real secret of nerve power. A more +constructive plan for utilizing their capacity was requisite at this +stage. Such a plan was eventually forthcoming. It was exactly what +might have been expected in the progressive development of any good +business concern; namely, consolidation. In effect, it was a merger +uniting the separate nerve units into one centralized system. How +this merger was brought about may be recognized in such animals as +the jellyfish (_Cœlenterates_). In them the body equipment consists +of an outside layer called the “exumbrella,” and an inner layer, the +“subumbrella.” In the latter the older arrangement of the nerve cells +as scattered, more or less independent stations still persists. These +stations form a net of communication on the under surface of the +animal. But where the subumbrella joins the exumbrella, making the rim +of the jellyfish, the nerve fibres and the nerve cells form a nervous +ring entirely surrounding the animal. This is the first time in the +history of animal life that an actual central nervous system makes +its appearance. This ring of nerve fibres and cells acts as a central +receiving and dispatching station. It is a central office for receiving +information from the outside world and a dispatcher for sending +orders to different portions of the animal so that all parts may +coöperate harmoniously. Certain special organs develop along the rim +of the jellyfish, whose functions have some bearing upon the sense of +direction. These structures are known as the marginal sense organs or +“lithocysts.” They are in direct communication with the central nervous +system. Certain other sense organs are also present in the form of red +or black specks of pigment at the bases of the tentacles; they are the +“ocelli,” which are sensitive to light and are, in fact, the simplest +form of eyes. Thus, in such low forms of animal life as the jellyfish, +the first signs of special sense organs made their appearance, and the +nervous elements were for the first time organized to form a central +governing mechanism for the animal. + + +_Nerve Concentration in Forming the Head_ + +Following the merger of the scattered nerve cells to form a central +system, the process of developing a brain had opportunity to advance +along another new line. The circular nervous system of the jellyfish +passed through many modifications as it adapted itself to the form +of different types of lowly animals. The great impulse thus imparted +toward the formation of the brain veered off in numerous directions +until a new and decisive change occurred in the arrangement of the +muscles. At this juncture certain animals appeared whose bodies were +much elongated and slender. Their muscles were arranged in straight +rows, one behind the other. Such an arrangement had definite advantages +for transportation, and these advantages were utilized by such animals +as the flat worms (_Platyhelminthes_). Many of the nerve cells and +fibres became concentrated in the head end of these animals. This head +region in a general way took the lead in directing the activities of +motion and transportation. It also had centralized in and about it +many of the most important structures of life. The animal at this +critical stage now possessed a head and a body. In the broadest sense +the development of such a head may be likened to the creation of a +definite executive office within which was established a supreme organ +to preside over the rest of the body. + +Further concentration of nerve cells in the head of the animal was the +next step in this constructive process. This advance added materially +to the centralization of nerve power, which was the keynote in the +formation and growth of the brain. + +If this process of successive upbuilding seems mysterious and almost +miraculous, especially from its feeble beginnings in a single cell, +it is scarcely more remarkable than the commonplace miracle that has +resulted in the development and birth of every newly created animal +since the dawn of time. The offspring of each species--fish or fowl, +beast or man--has its beginning in a single cell. It passes through +stages of cell colonization, of class distinction among cells, and of +specialization of organs for the various functions of life. + +In the main, these two processes have run parallel in their programmes +of construction--the beginning and development of life on our planet, +the beginning and growth of every new life created. Summarized thus +briefly, these successive stages necessary to bring the brain into +existence may appear unimpressive. But when we consider that each +forward step required ages for its achievement, we may appreciate that +this was indeed a marvel of progress. From nerve cell to brain is a few +short words in print; but it required millions of years for the slow +advances to attain even the humble level of the flat worms. + + +_Development of Better Brains_ + +With the head at length in its proper place and the most simple +kind of brain installed within it, vast horizons of life still lay +ahead. Better mechanisms were needed for a more successful struggle +with existence. More capable motors were required for more efficient +locomotion. These improvements came after the passage of long intervals +of time. By degrees more highly developed animals, such as bees, ants, +beetles, or other insects, lobsters, crayfish, and shrimp, began to +appear. Their brains were much better organized than those of the lowly +worms. The special senses of sight, smell, and taste became highly +important, while the central organ which presided over all activities +acquired a remarkable complexity in its structure. + +How much these animals gained from their better brain power is clearly +seen in their behaviour. The achievements of ants and bees and beetles, +as well as many other insects, have long been a matter of wonder, a +theme of interest and fascination. If we credit these animals with +highly capable brains, it is their just due. One detail in their +organization, however, became a serious handicap to them in their +further development. The passageway from the mouth to the stomach ran +directly through the centre of the brain. If the brain grew extensively +it would encroach upon the gullet, ultimately shutting off the only +channel for food. This embarrassment actually overtook many insects +like the mosquito. Here the brain became large. The tube connecting +the mouth and the stomach was thus reduced to a fine calibre, and +the animal was forced to depend upon the highly concentrated fluid +diet obtained by sucking blood. Coarser forms of food could not pass +the œsophageal ring which the brain forms about the gullet. Thus the +stomach and the brain came into serious competition with each other. +If the brain grew larger the stomach would be deprived of food. In +consequence, this situation created a dangerous hazard to life. + + +_Advent of Backboned Animals_ + +In addition to this stomach-brain dilemma, animals such as the insects +suffered from another handicap because of the outer skeleton which +protected their bodies. This skeleton was in the form of a more or +less rigid shell, as in the lobster, crab, or crayfish. It was to +overcome the effects of such handicaps, according to some authorities, +that the great race of backboned animals came into existence. In any +event, such animals seem to have circumvented the difficulty of having +a brain which surrounded the gullet. They also overcame the necessity +of carrying a heavy shell about on the outside of their bodies. An +inner skeleton did away with this embarrassment. It is not altogether +clear how or when this transition took place. Many students of this +matter believe that the basis for this change is to be found in the +starfish group of lower animals (_Echinoderms_). Others maintain +that the change began with some creature not unlike the horseshoe +crab (_Limulus_). It is also believed that the animals which served +as the intermediate forms for this advance were the ostracoderms, a +group which has long since become extinct. They are known to us only +through fossil preservations. They possessed, however, so many fishlike +features that they may well have served as the forerunners of the +earliest animals with backbones. Whatever else is in doubt, one detail +of this transition is definite. The brain, already well developed in +certain lower creatures, now received a fuller opportunity to advance +along more advantageous lines. The first gains of this kind are seen in +the fish. Judged by outward appearances the object of such new brain +development was to provide a more efficient regulator for a new and +more efficient kind of animal. The fish, in one particular at least, +showed higher specialization. It was built for speed in locomotion. +The shape of its body, the arrangement of its muscles, the position +of its fins, the design of its head, and the form of its tail gave it +many advantages over lower animals. Equally important were the special +organs by which it sensed the world. The fish possessed powerful and +remarkably constructed eyes. It had most delicate organs for smell, +and an effective apparatus for taste. In fact, all of the senses of +the body were now so thoroughly organized that each one of them had +its own special department in the brain. According to this new type of +administrative organization, an endbrain, an interbrain, a midbrain, +and a hindbrain were established for distinct departmental purposes. + +In spite of this better arrangement, there were still decided +limitations in the brain. The most serious of these deficiencies lay +in the mechanism regulating the energy turnover. The fish had little +power to withhold its reactions. Its impressions from the outside world +produced almost immediate responses. Such rapid reactions precluded the +wide range of acts which characterizes more deliberate behaviour. + +The brain machinery for the most ample kind of living was not yet +present at this stage of animal development. It did begin to make +its appearance, however, when certain of the fish assumed partial +adjustment to life on land. These adventurous pioneers managed to +crawl out of the muddy waters at times when there was a lack of +oxygen or when the supply of food was insufficient. They set on foot +those progressive changes that gave rise to fore and hind limbs in +such amphibians as the frogs. When these latter animals made their +appearance nearly all of the fundamental problems of the vertebrate +brain had been solved. Nevertheless, there was still the need of +certain expansions in brain power and these, in some part, were +supplied during the age of reptiles. + +As yet, however, that handicap of almost instantaneous reaction which +seriously limited the life of fish had not been entirely overcome by +the amphibian or by the reptile. These animals still lacked the brain +mechanisms needed for the deliberate and varied actions of the most +efficient life. They had not yet altogether escaped from the ancient +tyranny of automatic or reflex reaction. + +At length the mammals, throughout the different periods of their long +progressive age, introduced the final detail of brain perfection. The +secret of this perfecting detail was the addition of a new mechanism to +the brain never possessed by animals before this time. The great and +new areas of the cerebral hemispheres now came slowly into existence. +With them developed new and greater capacities for action together with +far more effective adjustments to life. + + +_Vast Ages of Animal Life_ + +All of these developments reach back a great distance in time, so +great that it is difficult to calculate its exact duration. According +to modern estimates the first animals came into existence about +1,000,000,000 years ago in the Proterozoic period. This period was +followed by the Palæozoic, which began approximately 300,000,000 years +ago, and is known as the Age of Fish. Then came the remarkable Age of +Reptiles, beginning about 200,000,000 years ago, followed by the Age of +Mammals, which commenced in the neighbourhood of 65,000,000 years ago. +The present Age of Man has had a short duration, extending back only +about 1,000,000 years. + +Two methods have been depended upon in determining these figures and +the age of the earth. The first is based upon the rate of deposit and +upbuilding of sedimentary rocks. The estimated period required for the +development of each rock layer has provided a time-table for the age of +the different strata of the earth’s crust. The second method calculates +the rate at which common salt is extracted from the land and deposited +in the oceans. Imprints of fossil animals upon the several rock layers +also reveal the age of different strata. The discovery of radium +afforded the latest gauge for estimating geologic time. The physicists +now tell us that former calculations have been far too modest and +that we must go back still further to reach the actual beginnings +of our earth. Their “radioactive clock” indicates that the earth is +1,600,000,000 years old. + +During all this vast interval there has been a succession of great +changes in the earth and its waters. Continents have risen above sea +level, to be submerged again. Great inundations of continental oceans +have swept inward and made vastly different land divisions from those +which exist to-day. North America has been more or less widely flooded +by great oceans at least fifteen times. Other continents have been +similarly inundated. Mountain ranges have risen and crumbled away by +erosion. In point of geologic time most of the present mountains are +relatively young. The oldest of these is the Appalachian range which +was formed during the Permian period approximately 230,000,000 years +ago. The Rocky Mountains appeared at the close of the Cretaceous, +100,000,000 years ago, while the Swiss Alps are of much later +development, having been formed at the close of the Miocene about +15,000,000 years ago. Even the Himalayas are relatively young when +compared with the earth’s antiquity. They had not taken on their full +gigantic proportions until the close of the Eocene about 45,000,000 +years ago. + +According to many authorities, great continental land connections +once existed between Africa and what is now part of South America. +This connecting continent disappeared beneath the ocean long ago. So +also did the land connection between Asia and North America in the +region of the Bering Sea. An important land connection existed between +England and the Continent, across what is now the English Channel, in +Pliocene times. It was present, therefore, at some time within the last +6,000,000 years. Immense inland seas have drained off or evaporated and +left in their places great desert spaces, like the Bad Lands of the +West. + + +_The Long Upward March Toward Humanity_ + +While these changes were in process marked alterations in climate +affected the surface of the earth. Glacial ice caps descended from +the poles, later to recede and leave the earth invested in tropical +warmth. Time and again these changes recurred. The crust of the earth, +chilled by intense refrigeration for protracted ages, grew warm again +for equally long periods when tropical vegetation crept up toward +the poles. These changes in vegetation have been accompanied by many +changes in the animal inhabitants of the globe. Species of animals +in profusion have come into existence only to follow the path which +led to extinction. In many cases the forms of life began simply and +progressed by graded stages to greater structural complexity. Man is an +outstanding example of this rule. He began in much simpler form than +that in which he now exists. This relative simplicity is particularly +true of his brain. + +Thus, as if descending a long stairway, we may pass by the successive +terraces of the earth’s history toward the beginnings of geologic +time. The expanse of this time is difficult to conceive. From the +inception of animal life in the long Proterozoic Age, throughout the +ages of Fish, Reptiles, and Mammals, man’s brain was in the making. +Irresistible forces molded the various stages of its progress. Species, +genera, families, and even entire orders of animals came into existence +and disappeared as wastage in a great experiment. Yet, through all +vicissitudes of time and change, the long upward march toward humanity +held its place. Ultimately it became the dominant feature in creation. +The advent of man introduced a new era. It remains to be seen whither +the forces moving in this Age of Man will take us. They may be leading +to extinction. The way to such a termination is clearly open to our +race. On the other hand, the brain has made man what he is and may +save him for better things. Its interesting pioneer ancestry, although +extremely remote, has left a well-established record. The history of +its development through the process of evolution in the backboned +animals is still more interesting. + + + + +CHAPTER II + +ANCESTORS BEFORE THE APES + +THE BRAIN FROM FISH TO MAN + + +_Practical Significance of Evolution_ + +There are many who still harbour resentment against the ape, especially +in explaining man’s origin. As a result, hostilities often flare up +against evolution. It cannot be denied that the unattractive ape is +at the root of these reactions. He is the bar sinister and the real +stumbling block in the evolutionary theory. He is also, to many people +at least, the entire gist of it. That we are descended from monkeys is +rather generally accepted as the meaning of evolution. This view, at +best, is a superficial explanation of what evolution really means. No +scientist to-day believes that any one of the living apes is ancestral +to man. These animals belong to families totally divergent from the +human family. They have ascended well up into the trees. Here doubtless +they will remain, quite as unconcerned in human origin as they are +innocent of participation in it. Our interest in evolution should not +centre upon the ape kind. The line of our ancestry reaches far back of +them through millions of years. We were in the making long before there +were any apes on earth. They, in their tree life, merely afforded the +last finishing touches which shaped our course toward humanity. If we +wish to acknowledge our hereditary indebtedness properly, we would be +compelled to recognize in our family tree that highly important line of +mammals which first introduced the custom of arboreal living. Back of +them are still older lines which deserve equal ancestral credit. Here +are found those animals without the existence of which we should never +have arrived. Among these is the vast assortment of reptiles, together +with mammal-like reptilians which appeared in the Age of Reptiles. All +of these reptilian forms were in their turn indebted for existence to +earlier amphibians and fish, their progenitors during the long Age of +Fish. Thus the true line of evolutionary descent leads us from fish +to man. Not until we appreciate the meaning of this long vertebrate +lineage through all its various phases does the vital significance of +evolution become clear. If we view it in this way it is possible to +sense the irresistible force that has carried animal life onward and +upward through the ages from the earliest times. This force may still +carry us onward. In its broader applications such a viewpoint should +make an urgent appeal for thoughtful consideration. It offers many +suggestions concerning further advances and readjustments in human +behaviour. + + +_Evidence of Evolution in Our Bodies_ + +The brain is one of the best witnesses testifying to this long +evolutionary development of man. It contains convincing evidence of +this process in three striking particulars. First, it gives numerous +signs indicating its primitive origin from the lowest of the +vertebrates, the fish. Second, it bears identifying marks of intimate +association with animals of its own class, the mammals. Third, it +has a large number of details in its special mechanisms possessed in +common with all of the primate order, to which man belongs together +with the lemurs, tarsiers, monkeys, and apes. This evidence is not +circumstantial. It is direct and unimpeachable. It leaves no point in +the line of man’s long descent to be decided by inference. It embodies +factors which led, step by step, to the upbuilding of the human brain. + +Other tissues and organs of the body tell the same story of slow, +steady progress upward, from some low and simple phase of life, through +many graded stages of improvement until the human form at length came +in sight. + +The blood has been an especially positive witness concerning this +progressive development. Tests with many different kinds of animals +show that the blood of man is much nearer to that of the great apes +than to the lower Old World monkeys. The relation between the human +blood and that of the New World monkeys is still more remote. In +general, these blood tests are among the most convincing proofs of +evolution. + +The bony system of the body is another decisive witness. The skeleton +of the fore and hind limbs sheds much light on the changing adjustments +which have been made in the motor apparatus. The use of the limbs as +fins, paddles, wings, hoofs, paws, claws, hands, or feet, indicates +the broad family relations and kinship of various animals. The size and +shape of the skull and the character of the teeth reveal the manner in +which this evolutionary process has passed through its several stages. +The muscular system, the system for eliminating waste products of +the body, the heart and the lungs, all afford important evidence of +vertebrate kinship and evolution. The increase in the complexity of the +breathing apparatus, from the early gill stages of the fish to the lung +of the mammal, through all its many intermediate phases, discloses with +astonishing clearness the course of this progress. + + +_The Embryo as a Witness_ + +Testimony from another source also stands undisputed. This +corroboration comes from the manner in which all vertebrates are +conceived and formed. The witness in this case is the embryo, which in +all animals begins in the same way. Embryonic existence starts from a +single cell. It holds true to the earliest beginnings of animal life +that first appeared in a single cell such as the amœba. In the higher +animals this cell is called the ovum. From it, after fertilization, +two cells are derived, then four, then eight, then sixteen, until it +has an appearance closely resembling some of the colonized protozoan +animals. Here again, even in man, is seen that decisive stage in which +a critical cellular distinction is made between outside and inside +cells. From this time specializing progress in the growing individual +goes forward. Each new phase repeats in a general way a stage of +development previously attained in the evolution of life. All embryos +of vertebrate animals pass through such phases. The fish embryo carries +the process up to the stage characterized by those improvements which +developed during the Age of Fish. The amphibian embryo takes the +process one step farther. It adds new features essential to living +on land. Embryos of reptiles and of birds introduce the progressive +advancements peculiar to their kinds. The mammal embryo takes the +final step, prior to which it passes successively through the several +phases of the lower grades of life. The human embryo follows the +mammalian plan and puts the finishing touches of development upon what +the mammal has gained from all the stages below it. Fish, amphibians, +reptiles--all have their beginning in a single cell. Regardless of the +differences in body form, in mode of life, and in behaviour, all are +cast in a mold of development based on a common design. Thus, while the +blood, the bony system, the muscles, the teeth, the eliminating system, +the heart, and the lungs tell the story of progressive development, the +embryo gives a summary of this process by disclosing the general plan +which underlies the manner in which every backboned animal is formed. + +The brain contains a comprehensive record of this progress. There are +reasons why this is the case. Brain influences pervade and dominate all +other systems. This organ is the great transformer of energy, which so +assembles other parts in operation that the body as a whole becomes +a smoothly acting machine. It receives sensory impressions from its +environment. It controls the reactions incited by these impressions. +In this dual capacity the brain has been especially sensitive to +those influences of change and adjustment, of action, reaction, and +interaction that have affected animal life during its long existence. +It has responded to these changes and has retained the impression +of such responses. In many cases it has been structurally improved. +Gradually it became capable of sensing the world more effectively. It +acquired the capacity to react on a broader scale. Developing along +certain progressive lines it has served to transform impressions +received from the senses in such a way as to produce an increasingly +more effective turnover of nervous energy. For this reason it is +necessary for us to estimate the value of such senses as were utilized +in this way. Without going too extensively into detail, it may be said +that, with extremely few exceptions, vertebrate animals possess four +chief varieties of sense. Each of these supplies the brain with stimuli +necessary to its proper reaction. + + +_Value of Our Senses_ + +First, chemical sense, through special organs for smell and taste, +conveys information concerning certain chemical conditions in the +surroundings. The sense of smell derives its impressions from gaseous +or volatile substances which, among other things, may create a pleasant +or a disagreeable odour important in selecting food. The sense of taste +gathers its information from substances in solution. It depends upon +acid, sweet, bitter, salty, or other similar stimuli. The primitive +headquarters for taste are in the hindbrain, while the endbrain serves +in this capacity for the sense of smell. + +Second, body sense furnishes information concerning what transpires +within the body, as in the heart and lungs, in the stomach and +intestines, and in other special organs. It also supplies equally +important information concerning what contraction is occurring in the +muscles, how the bones are being moved, what postures the different +parts are assuming, and how the body as a whole is being balanced. + +Third, contact sense makes known what is going on immediately outside +the body. It depends upon many things which touch the body surfaces, +such as the touch and pressure of a handclasp, the temperature of +water upon the hand, the vibration of a heavy vehicle running over the +ground. Body and contact senses had their original headquarters in the +midbrain and interbrain. + +Fourth, distance sense supplies information concerning objects in the +world outside of the body more or less remote from it. The information +which this sense brings is news from abroad. It is gathered by the +sense of sight and the sense of hearing. Sight, in a way, is touch at a +distance. When an animal sees its enemy a long way off it, so to speak, +touches this enemy with its eyes and thus gives the brain the needed +information while there is yet time for escape. Sight depends upon +light waves, and hearing upon sound waves. By such means these two +highly specialized agents of distance sense gather their information. +The central offices of sight and hearing were at first situated in the +midbrain. + +All impressions obtained from these senses were and still are the raw +materials utilized in the energy turnover produced by the brain. + +Improvement was not always the result of the great struggle for +adjustment. There were many ups and downs, many trials, many failures. +Yet a certain insistent tendency toward progress was constantly in +evidence. By means not entirely clear, this tendency ultimately +succeeded in finding some way to become effective. It appears to +have exerted its influence by selecting definite parts of the animal +machinery for emphasis or repression. + +Often some highly selective improvement was developed in the brain to +meet special conditions. Such is the expansion in the bird’s brain by +which the sense of sight is greatly amplified. This special increase +makes it possible for the bird to see its prey from great distances in +the air, as the hawk sees the fish in the water, or the vulture detects +the presence of carrion by its keen eyesight. The sense of smell in +birds is much less developed than vision. + +In scenting animals, like the dog, the fox, and the cat, selective +improvement has affected the sense of smell. In a few instances the +addition of a relatively new sense was the means by which improvement +manifested itself. Such an addition is seen in that transition when +fish life first began to assume the characters of living upon land. At +that juncture the sense of hearing was added in some amphibious animals +belonging to the same class as the frog. These and other methods for +getting a better supply of raw materials through the senses contributed +to progressive development in the brain. + + +_The Sense Combiner_ + +Still more effective was the improvement which came as a new mechanism. +It provided a special apparatus that may for convenience be called the +“sense combiner.” The office of this mechanism was to assemble sense +impressions in the brain, to make composite pictures of sight, hearing, +taste, smell, and all other senses. This sense combiner served also +as an effective depository for impressions already received. It held +them in readiness for use as a background of experience that would be +needed for new or subsequent situations. At a glance it is evident that +the brain having the best sense combiner would outstrip all others +in its efficiency and output. In the earliest vertebrates this new +mechanism did not acquire a centralized headquarters. Its operations +were controlled from several scattered stations in the brain. Obviously +such division of responsibility could not be considered an efficient +method of control. Centralization was needed, and certain stages in +the development of the brain from fish to man illustrate how this +improvement was gradually brought about. + +The first or fish stage, as might be expected, expresses the beginning +of this process of improvement in simplest terms. There are many who +do not credit the fish with such a thing as a brain. These animals, +however, are equipped with an effective organ of this kind. Its +efficiency is not high according to human standards, yet, as we shall +presently see, it has many characteristics of the human organ and +reacts to similar stimuli. + +In the fish brain there are nearly all of the working departments +found in man. Much variation exists even among fish. Some of them have +very simple brains. This is true of the earliest forms, but the more +advanced types acquired brains thoroughly efficient for the special +complexities of existence in which they had to live. The several +departments in these brains are adjusted to their requirements. The +sense of smell in the fish is particularly well developed. It has +certain limitations, however, due to the fact that it must depend +upon substances borne by the water. The department of this sense, +nevertheless, occupies the major portion of what in these descriptions +will be called the endbrain. The sense of taste is also well organized +in fish. In certain of them, like the catfish, it has received special +emphasis, because in addition to taste organs in the mouth there are +organs of this kind scattered over the entire body from head to tail. +The primitive central office of the sense of taste in fish is located +in the hindbrain. Body sense is highly developed because most of the +fishes are able to control their muscles and joints in an amazing way +as they dart about in the water. Balancing of the body in swimming is +another important problem in the locomotion of the fish. It is solved +by means of certain highly specialized water levels (semicircular +canals). The body sense department occupies the interbrain. The sense +of sight in most fish is fairly well advanced, although it has distinct +limitations. Being placed on the side of the head, each eye acts more +or less independently of the other, and the fish, so to speak, gets a +two-eyed picture of its surroundings. It will subsequently become clear +that one of the most important events in the progress of the brain has +been the development of that kind of vision in which both eyes receive +the impression of an object at the same time. Then again, the medium +in which the fish lives is in many respects less favourable for the +passage of light rays than the air. The retina of the fish’s eye which +first receives the light rays also indicates a relative simplicity in +the organization of vision. For these and other reasons the fish’s +sense of sight cannot be as effective as in the higher forms of life. +This sense department is located in the midbrain. + + +_Starting with the Fish_ + +The fish stage in the development of the brain shows a striking +deficiency in its lack of provision for a sense of hearing. Strictly +speaking, fish have no ears. It is believed that the ability to hear +which the human being possesses is denied to them. In still another +respect, however, a more obvious deficiency makes itself apparent. +The brain is poorly equipped in mechanisms that could specifically +be called sense combiners. Some slight degree of combination between +the senses does take place, but this at best is meagre and simple. +Consequently the brain’s output, that is to say, its productive +turnover, is limited. It confines itself to those reaction patterns +with which we are familiar in the habits and behaviour of fish. The +limitations by which these patterns are restricted are evident in the +fact that the animal’s entire life programme is carried on largely +under water. If an attempt were made to estimate the capabilities of +the fish as a machine compared with other animals, it would almost +certainly receive a low rating. The justification of this low estimate +is obvious. The reasons for it are twofold: first, the relatively low +degree of development in each of the sense departments including the +lack in one department (sense of hearing); second, the poorly developed +sense combiner. + +Professor Gregory has devoted much time in the American Museum of +Natural History to the study of the progressive stages from fish to +man, and especially to those changes which appear in the head. He has +shown that in this fish stage the animal at first had no lower jaw and +no teeth. Its mouth served as a sucking organ, which thus obtained food +in the form of minute organisms and small particles of organic matter. +Certain new patterns were introduced with the appearance of primitive +sharks. These animals had a lower jaw impregnated with lime salts, +thus made effective for supporting many successive rows of formidable +teeth. Such sharks also had well-developed gills. Certain lobe-finned +fishes of a somewhat later period (_Crossopterygian_) began to live in +streams and swamps. By means of their peculiar fins they were able to +crawl over the surface of the land, and thus they were the forerunners +of the next more completely air-breathing stage determined by the +appearance of the amphibians. + + +_The Beginning of Life on Land_ + +The second or amphibian stage came after those steps had been taken +which led certain modified forms of fish life to attempt a partial +adjustment to living on land and to breathing air. True amphibians +then made their appearance. Animals called tetrapods, or four-footed +creatures, were the result of this change. They were the forerunners of +all higher animals. By the slow conversion of their fins and paddles +into legs they acquired a new kind of transportation machinery. With +the aid of these four legs the animal could now hop about on land and +also swim in the water much as do the frogs. Such a transformation +had a profound effect upon the entire body, which became greatly +shortened and in many instances no longer possessed a tail (except in +the polliwog stage). The head also changed. New devices were necessary +for the purposes of air-breathing, which replaced the old method of +getting oxygen out of the water. One of the most important changes, +however, was the addition of the new sense of hearing. The amphibians, +living partly on land, were now able to receive useful information by +means of air waves. The advent of this new sense was destined to have +momentous effects upon the further development of the brain. Each of +the several sense departments is well represented in the frog. The +sense of smell is highly organized. It contains some improvements over +the fish for the reason that the animal is now able to scent odours +borne by the air. The sense of taste shows little if any improvement. +Compared with many of the fish it has actually receded. Body sense is +well provided for and shows certain refinements due to the fact that +it has taken on the new responsibility of sensing four legs. It also +has the duty of supervising what is going on in the muscular machine +when the animal performs its new kind of motion, hopping about over +the ground, leaping into the water, or using the new frog-method of +swimming. The department of the sense of sight shows some improvements +when contrasted with that of the fish. The frog is able to adjust its +vision both to air and water. While on land it is able to see many +things that never come into the range of the fish’s field of vision. +Some of the frogs even go so far as to have what is called a third +eye in the middle of the forehead. This organ, however, is but poorly +developed and serves more for light perception than for actual seeing. +The introduction of the sense of hearing, by establishing certain +innovations in the frog brain, provides an advantage over the fish. It +is, however, in furthering the development of the sense combiner that +the frog’s brain shows its most distinctive advance. The two great +hemispheres are now clearly outlined. The endbrain, in consequence of +land-living and air-breathing, has taken an important step forward. In +all further advances this part will bear the chief burdens of progress +and improvement. + +The frog and his kind represent a machine that in many respects is +not much better organized than the fish. But amphibians did serve to +introduce advantages that were utilized in new adjustments to life; +such, for example, as living on land, breathing air, getting about on +four legs, and being able to hear. Besides this, the way was now opened +for a better type of sense combiner. There was promise, if not actual +profit, in these new amphibian endowments. Professor Gregory has shown +that among the most important changes in the amphibian head were those +which ultimately led to the formation of the ear. The skin in this +region was already beginning to act as a tympanic member or eardrum. + + +_Epoch of Giant Reptiles_ + +The third or reptile stage witnessed that critical advance that came +with the fully established habit of living on land. The amphibians, +both those which retained and those which lost the tail, took the +first somewhat hesitating steps in this direction. They were, however, +essential predecessors to the next higher order, the reptiles, which +upon their arrival stepped out boldly. During the remarkable Mesozoic +period these reptiles covered the earth with their dominating and +often hideous presence. No period compares with this one for the +awe-inspiring inhabitants that peopled the world. It was then that +the gigantic dinosaurs were the overlords of creation. Some of these +monstrous creatures were composed of many tons of flesh and bone. They +became the most terrific fighting machines ever produced by nature. +Even the tail, which had disappeared in many of the amphibians, became +prominent as part of the offensive equipment in these reptile monsters. +Gigantic size was an outstanding structural feature. But these huge +dimensions carried their own penalties. They were extremely hazardous +and destined to bring catastrophe. Even if some of the great reptiles +might have been thoroughly efficient fighting machines, they lacked +the essential advantages of progressive brains and brain power. In +this respect they had improved but little. That tremendous monster +_Tyrannosaurus rex_, the most destructive engine ever created, had a +body weighing many tons, with a brain of less than a pound. + +The prolific Mesozoic reptiles inhabited the land and infested the +waters of the earth, its oceans and inland seas, its lakes and rivers. +They also for the first time attempted to realize the advantages +of another mode of life. Having adjusted their weird bodies to +the water and to the land, they next took to the air. Late in the +Permian or Triassic times (150,000,000 years ago) some lizard-like +reptiles, partially biped in habit and distantly related to the great +two-legged dinosaurs, assumed habits of life adapted in part to the +trees. Specialization of their fore limbs led to wing-like structures +for purposes of volplaning to the ground. Such modified fore limbs +eventually acquired the character of wings, and thus, according to +some authorities, the most ancient of known birds had their origin in +the Age of Reptiles. Many students of this subject believe that bird +life may have begun at an even earlier period. + +More conservative and also far less conspicuous was another tendency +which developed in this reptilian age. For a long time it remained most +unpretentious. The spectacular development of huge animals for land and +sea held the centre of the stage. Mere size, however, is not always +sufficient for success and progress. In any event, a certain number +of relatively small reptiles began to show changes along entirely +different lines. At first it was difficult to discern the signs of +progress in them. Slowly, however, significant modifications came about +in two important details: First, in the readjustment of the fore and +hind legs, so that acting together they began to lift the body of the +animal clear off the ground. The second great change was an alteration +in the teeth, which were gradually specialized until they assumed the +characters recognized in those later animals known as mammals. These +two new traits, developed by relatively inconspicuous reptiles, led in +time to animals that became the actual forerunners of the mammals. They +are known as the pro-mammalian reptiles (_Cynodont_, _Theriodont_). + + +_Reptile Forerunners of the Mammals_ + +It is probable that while these momentous changes were in process an +equally important modification had begun. This change affected the +blood. It caused the blood cells to become smaller and at the same +time better conveyers of oxygen. These cells also began to lose their +nuclei. As a result, certain animals passed from a cold-blooded, +scaly reptilian condition to that of the warm-blooded, hair-covered +mammal. The constant warm temperature of the blood in these mammalian +forerunners must have been a decisive influence favouring the further +development of the brain. + +In many respects the reptilian brain is inferior to that of the +mammals. All of its sense departments are fairly well represented. +The senses of smell and taste have made slight advances over the +amphibian stage. Body and contact senses have perhaps gained some +slight advantage over the previous period. In sight and hearing there +were some improvements. Collectively the reptilian mechanisms for +managing impressions obtained through the senses are considerably +better than those of such animals as the amphibious frog. At least one +of the reptiles (_Sphenodon_) developed a third eye in the middle of +the forehead. This is not, however, a highly efficient visual organ. +The sense combiner in the reptile also shows some advantage, although +in the main the reptilians appear to have acquired little more of +practical value, except greater speed and more power, than their +predecessors, the amphibians. + +Even when reptile development took that bent which led to the +appearance of birds, the brain received but a slight benefit from this +adjustment to the air. Selective progress in the bird’s brain is +unquestionably found in that marked expansion involving the department +of sight. Body sense also expanded to meet the requirements of sensing +and balancing the body in flight. But to offset these advances both +the sense of smell and the sense of taste have undergone considerable +recession. Adaptive progress here, as in many other instances, +emphasized one department with some apparent loss of advantage in other +parts. Consequently the sense combiner, which ultimately produces +the most effective combinations of sense impressions, has shown no +conspicuous advantage among the birds. + + +_Disappearance of the Great Reptiles_ + +The reptile stage of life, especially in its most imposing phases, +witnessed but little advance in the progressive development of the +brain. During this period all of the great departments of brain +structure, such as the endbrain, the interbrain, the midbrain, and +the hindbrain, were retained and somewhat expanded. But that highly +important mechanism that was finally to act as the superbrain, +technically known as the neopallium (new outer coating of the brain, +the cortex), had not yet been acquired. It may be in part for this +reason that, as the Mesozoic period advanced, catastrophe was rapidly +overtaking many of the great reptilian groups. Of the eighteen orders +of reptiles that once filled the world, all but five were mysteriously +swept into oblivion. Why they passed is not yet clear. It may have +been due to great changes in the surface and climate of the earth +at different times. It may have been that the gigantic size of these +reptiles made the struggle for existence too severe or the food +supply too precarious. Whatever the cause, they all seem to have +paid the penalty of excessive specialization. The five orders which +have survived these destructive catastrophes include the snakes, the +crocodiles, the lizards, the turtles, and the lizard-like tuateras of +New Zealand. + +Notwithstanding this wholesale destruction, there was a priceless +heritage handed down from the Age of Reptiles. This heirloom was the +beginning of the warm-blooded mammal, which slowly developed from +the humble pro-mammalian reptiles. It endowed the animals that were +to rule the next great period of the earth’s history with power to +get about on four feet, with increased ability to withstand great +changes of climate, with added capacities in preparing their food for +digestion. This last advantage depended upon a new kind of teeth which +the mammals inherited from their immediate reptilian ancestors. All of +the teeth possessed by primitive reptiles were fang-like (laniary), +used for seizing their prey or tearing their food. These reptiles +had no grinding teeth, and this condition left the responsibility of +digestion to the stomach and other organs. In most of the mammals +digestion begins in the mouth with actual mastication. The early +pro-mammalian reptiles (_Cynodonts_) were equipped with grinding teeth, +and their dental apparatus, as in all mammals, included incisors, +canines, pre-molars, and molars. Teeth such as these were important +items in the legacy received by the mammals from their ancestors, the +pro-mammalian reptiles. + + +_When the Warm-blooded Mammal Appeared_ + +In the fourth or mammalian stage, life entered upon the Age of Mammals +with all of these new endowments. Almost at once it began to show +signs of progress. It was in the brain that this progress became most +apparent. A new mechanism long in the making now came into existence. +This new structure may be rightly called the superbrain (neopallium), +since it soon proved to be the most decisive step yet taken in the +development of the sense combiner and in the further expansion of all +the senses. At first it did not make its appearance in any preëminent +manner. It came as an outer covering over the ancient parts of the +endbrain. Within it, however, were possibilities of expansion such +as were possessed by no other part of the brain. Ultimately it added +about twelve billion cells to be used in many different kinds of +brain activity. This addition was especially characterized by the +orderly arrangement of the cells, layer upon layer, almost as if each +successive layer imparted some new capacity for the management of life. +In its fully developed form this structure constitutes the cortex of +the hemispheres, and with its fibre connections makes up as much as +eighty per cent. of the entire brain. + +It could hardly be expected, even after the first arrival of the +mammals, that this new brain addition would at once attain its +fullest development. In fact, the first attempts along this line were +feeble. A new and great production of weird mammals was in process. +It might almost seem as if the imposing shadows of the previous Age +of Reptiles still hung over these early mammalian experiments. Huge, +ungainly proportions were still the fashion. In many instances the +primitive mammals themselves developed gigantic and awkward bodies. +They were strange, unsightly beasts as we know them now from their +fossilized skeletons and from reconstructions of them. Were it +possible to reassemble them, what a sensation they would create in +our modern world. Even the best efforts of our foremost showmen would +be ineffective to describe those strange monsters of most unfamiliar +appearance, with their peculiar armours, their long unsightly horns and +tusks, their strange hoofs and claws. The mammoth, the mastodon, the +amblypod, the titanothere, the creodont, the sabre-toothed tiger, and +many others would be among them to excite wonder. + + +_The Paths to Extinction and Progress_ + +But all of these have passed, in part at least, because, like the +dinosaurs, they possessed inferior or unprogressive brains. Indeed, +many of the earliest mammals had brains that in some particulars +resembled those of the reptiles. They grew in size and power until they +became repulsive brutes, although their brains improved but little. +In many of them the superbrain developed only in a small way. It was +notable not for its size but for the position it occupied above more +ancient structures. In their struggle for life these huge beasts seemed +to be unable to adjust themselves to changing environment; so probably +when the conditions became too severe, not having the capacity to adapt +themselves, they failed to survive. Many orders of these animals became +extinct in the early part of the Age of Mammals (Oligocene and Eocene, +thirty million to sixty-five million years ago). Others, showing more +progressive tendencies, continued to advance, and their descendants +have come down into modern times. One striking difference between these +progressive and unprogressive mammals was certainly in the brain. +Wherever this organ remained primitive, wherever the superbrain was +only feebly developed, the fate of extinction seems to have been a +foregone conclusion. Such animals soon reached the end of their line. +But wherever the superbrain expanded, there the signs of progress were +unmistakable. One extremely important factor in the survival of most +of the mammals alive to-day was the progressive development in the +most recently acquired portion of the brain. Great practical results +were brought about by its expansion in the administration of brain +power. It produced, so to speak, the final consolidation of all the +sense departments under one roof. Reactions connected with the sense +of smell and of taste, which had so long depended upon the primitive +endbrain, marked this structure as the most advantageous location +for centralization. Whatever may have been the influences that +established this preference, here the departments of body and contact +senses, of sight and hearing, were finally organized. The effects of +this consolidation were immediately felt by the endbrain. It at once +became a superbrain in the truest sense. Rapid expansions in the actual +size of the hemispheres were the first signs of this new development. +Then came the process of convolution and folding to obtain more brain +room, and this for the same reason was followed by still more complex +convoluting. These advantages especially favoured contact sense, the +expansion of which was largely due to the fact that the mammal body +was now covered with a highly sensitive skin equipped with hair. Such +a skin was a new sensory device by which finer impressions of touch +might be conveyed to the brain. In this manner the animal was able to +form more complete judgments concerning objects with which it came +in contact. Little by little, these judgments of touch became more +critical and discriminating. A great range of understanding of the +world through touch sense was made available. One critical impression +of touch was added to another until complex judgments in this sense +were constructed. Similar expansions in the powers of vision, hearing, +and body sense led to their localization in this new part of the +brain. Their most effective activity soon required still further +extension, which ultimately, by the development of the frontal lobe, +made provision for the highest faculties. The mammals have thus shown +their progressive tendency in the acquisition of an efficient sense +combiner. Through their better sense capacities they have been able +to understand their surroundings more thoroughly than lower animals. +Consequently their energy turnover in the brain has resulted in a +better output by means of which they have made more ample adjustments +to life. All of this they have been able to accomplish because they +possessed a mechanism of incalculable value, the superbrain. Yet the +mammals have not in all cases utilized this mechanism to its full +extent. Its advantages have been applied in different ways and for +different purposes. In some instances they have been utilized for the +special adjustments of the hoofed animals, or in the hunting craft of +the great meat-eaters, or in that furtiveness of the moles, which seek +their protection by burrowing in the ground. The advantages of the +superbrain were applied to many other diverse specializations, such as +the adjustments of bats for flying, or of beavers, seals, whales, and +porpoises for living in the water. + + +_The Superior Brain of Mammals_ + +The mammalian brain has made possible a wide range of behaviour and +adjustment. This range exceeds that of the fish, amphibian, reptile, or +bird. Concerning the increased capacity of the mammals as a class there +seems to be no doubt. But this greater power of adaptability is also +true of every mammal. The differences in this respect between the lower +mammals, like the rat, the opossum, or the sloth, when compared with +the bird, the snake, the frog, or even the fish, may not be striking. +But when we contrast the actions and capabilities of such mammals as +dogs, horses, elephants, or any of the cat family with those of the +bird or snake the vast differences speak for themselves. A dog, for +example, has by comparison with lower vertebrates a greatly increased +capacity for getting on in life. He is capable of adapting himself to +many complications incident to his associations with man. He has a much +more ample repertoire of performances. He is capable of learning many +intricate accomplishments. In general, such learning is also true of +most of the higher mammals; it is particularly true of those having a +highly developed superbrain. Even aquatic mammals like the seals show a +remarkable degree of adaptability. They are among the most interesting +of trained performers. A casual glance is sufficient to reveal what an +excellent superbrain they possess. Elephants, in spite of their huge +proportions and awkwardness, are capable of remarkable adjustments. +Their brains are also highly developed. + +Yet, however decisive the mammalian superiority in brain power may be +over the lower vertebrates, most of the mammals are held down by many +handicaps, restrictions, and limitations. They all possess a capacity +for broad adjustments to strictly limited conditions. For life in the +water, in the air, upon the plains, underground, or in the forest, +they may be well adapted. But the specializations of their own bodies +hold them to their specifically restricted adjustments. With trunk and +head, with hoof and paw, with wing and flipper, they may do the things +which these implements make possible. Here their opportunities cease. +In this way even the progressive mammals are confronted by serious +obstacles. These mammalian obstacles were difficult to overcome. Some +of the mammals, however, became specialized for a more varied kind +of life. They manifested a strong tendency to live chiefly in the +trees. This fact influenced their further adjustments profoundly. It +opened the way for new specializations in their limbs. It gave a new +direction to progress, which finally called upon the brain for its +supreme development. These important tree-living animals are the monkey +kind and the manlike apes. All of the events in adjustment preceding +this great epoch might be likened diagrammatically to a succession of +plateaus. Each plateau, beginning with that of the fish, then rising +to the level of the amphibians, of the reptiles, and finally of the +mammals, contributed some important elements to progress. From these at +length came the upper level of the apes, that plateau destined to give +rise to many varieties of primates, and also to afford those footholds +essential to the further upward climb of man. + + + + +CHAPTER III + +MAN IN THE MAKING + +HUMAN PROGRESS FROM PREHISTORIC TO MODERN TIMES + + +_Arrival of Man_ + +Long before man appeared upon the scene the brain had passed through +certain preliminary grades. Its basic patterns had been perfected. Its +most important mechanisms had been improved. All manner of animals +inhabited the earth in those preparatory days--fishes, amphibians, +reptiles, birds, and mammals of many varieties. They were the stepping +stones of progress. When at length the first members of our family +arrived their brains were barely human, and they themselves were crude +human beings. There was a certain triumph in their advent, however, for +at last there were men. The Age of Man which they inaugurated was to +differ from all preceding ages in the products of human achievement. +This great inaugural event, however, made no particular stir in nature. +Its beginnings were insignificant and humble, just as the brain of +these earliest men was a far less imposing organ than that possessed +by modern people. It was still a crude brain, unrefined in many of its +structural details and small in its capacity. Hundreds of thousands +of years were still necessary for such a brain to attain its highest +efficiency. + +To most of us who are accustomed to count time as the hours between +breakfast and dinner, or, at the most, as the proverbial threescore +years and ten, these long periods sound fabulous and fantastic. In +contemplating the past our vision usually stops short at the beginning +of history, about five or six thousand years ago. Such a focus is +unfortunately nearsighted. It leaves us insensitive to the much longer +prehistoric period. Through all this unrecorded time man struggled +upward to achieve those successes which at length established the Age +of the Frontal Lobe. + +Much evidence of this great prehistoric period is now available. +Examined carefully and without prejudice it reveals what man must have +been when his human journey first started. It tells us much of how he +lived and acted; also by what means he succeeded in lifting himself up +step by step from his lowly beginnings. + + +_The Duration of Human Existence_ + +It is natural that our first inquiry should be concerning the length +of time during which the human race has inhabited the earth. The +exact figures, as might be expected, are a matter of much dispute +and difference of opinion. All authorities, however, agree that the +several stages of human progress must have required a remarkably long +period. None of the modern estimations of this period is less than +five hundred thousand years. Many calculations, such as those of Sir +Arthur Keith, far exceed this figure and place the origin of man as far +back as a million years or more. The beginnings of the human species +are usually attributed to the early part of the Pleistocene, or the +late part of the Pliocene. Keith, however, believes this does not +permit of sufficient time for that development which produced all of +the effects evidenced in the known features of modern man, as well as +those of certain extinct varieties that have long since passed from +the human stage. Concluding his famous work, the _Antiquity of Man_, +Keith expresses the opinion that “There is not a single fact known to +me which makes the existence of the human form in the Miocene period +an impossibility.” This view would set the origin of man back to an +astonishingly remote period in the neighbourhood of twelve or fifteen +million years ago. + +Professor Osborn has recently revised his original estimations +concerning the beginning of the human race. He now attributes the rise +of man to a time one and a half million years ago. + +In all his races, both living and extinct, man constitutes the sixth +family in the primate suborder, _Anthropoidea_ (manlike). This family +is known as the _Hominidæ_ (men of all types). The progenitors of the +human family split off from a common primate stock at some time early +in the Oligocene. At this critical juncture, probably twenty-five +million years ago, two great branches of the suborder parted company. +Thenceforth they developed independently of each other. The first +branch from this common stem gave rise to human races. From the +second branch arose the great modern anthropoid apes, including the +orang-outang, the chimpanzee, and the gorilla. The vast difference +that exists between man and all other living creatures is evident in +the complexity of human affairs. In size and form of body there are +many notable resemblances between man and the apes, particularly the +great apes. But here the similarity ends abruptly. Man has created a +new world, which he strives to control both by laws of his own making +and by subjugating more or less completely all other creatures to his +will. His races to-day throughout the world are collectively known as +the species _Homo sapiens_ (man of wisdom). This species comprises the +African, the Australian, the Mongolian, and the European varieties of +mankind. + + +_Four Extinct Races of Men_ + +Study of human fossils and ancient implements has revealed the former +existence of at least four prehistoric races of man. These races took +their parts in the human drama and then, in consequence of factors +not altogether clear, became extinct. It is not surprising that man’s +obscure prehistoric beginnings are all but lost in the great geological +ages which lie behind his recorded history. There can be small wonder +that such insignificant traces of his remains have yet been brought to +light. The search for these remains has been in progress for little +more than a century. Doubtless when this exploration becomes more +extensive, also when more people are engaged in its organization, a +considerable collection of relics revealing man’s primitive stages will +be discovered. Nothing more than a meagre record could be expected +because so little effort was originally made to preserve the remains +of the earliest prehistoric men. In those long-distant days the bodies +of the dead were either disposed of by burning, or merely cast out to +be devoured by beasts and birds of prey. + +The principal criteria for estimating the antiquity of human remains +are four in number. First, the age in geological time of the strata +within which the remains are found. Second, the fossil remains of +the animals associated with the fossil remains of man, whether these +be of still living forms, or entirely extinct species. Third, the +human artifacts, that is, implements, ornaments, and other objects +produced by human hands, found with the remains. Fourth, the structural +characteristics as to skull and other parts of the skeleton, which +distinguish these fossil men from living races. + +Quite as important as the fossilized bodily remains of prehistoric man +are those ancient works of human hands that have been slowly collected +as a result of untiring search and scientific industry. It is now +possible to classify this great body of evidence. Besides revealing +the actual presence on earth of prehistoric man, this classification +clearly demonstrates the occurrence of certain cultural stages prior to +the historic period. The extinct races of men already brought to light +appear to vary considerably from the modern man; so much so, in fact, +that a question has been raised concerning the wisdom of creating for +each of them a new genus within the human family. One reason for this +distinction is that no one of the extinct races may properly be called +the ancestor of living man. Some arrangement in the chronological order +of man’s appearance on earth is desirable. The exact period of each +extinct race cannot be given. But within certain broad limits we are +able to assign each prehistoric man to his proper time and place. + + +_Javan Ape Man_ + +Probably the oldest, most primitive of extinct races is the ape man +of Java (_Pithecanthropus erectus_). This ape man belonged to what is +called the Trinil race, which, according to Keith, originated more than +one million years ago. The ape man, although definitely human in type, +had many simian qualities. He was also so similar to man as to justify +the view that he represents some transitional stage in human evolution. +He possessed a head and a face not unlike those of an ape, but his +brain was nearly twice the size of the brain of any simian including +the largest of the great apes, the gorilla. It was this transcendent +advantage that lifted him above all of the anthropoids and assured him +an unassailable place as a member of the human family. + +The fossil remains of the ape man were discovered in 1891 by a Dutch +army surgeon. Dr. Eugen Du Bois made the discovery on the Bengawan +River in central Java where he had been excavating in the hope of +finding pre-human fossils. He actually did find a number of mammalian +bones, including a single upper molar tooth, which he regarded as +those of a new species of ape. On carefully clearing away the rock +and gravel at this site on the bank of the river, the top of a skull +came to view about a yard from the spot where the tooth had been found. +Further excavation brought to light a second molar tooth and a left +thigh bone. Both of these were about fifteen yards from the place where +the skull had been discovered. These scattered parts were carefully +studied by Du Bois, who, in 1894, published a description of a new +animal--_Pithecanthropus erectus_ (_Pithecus_, ape; _Anthropus_, man). +The entire term was meant to signify an upright standing ape man. The +word “_erectus_” refers to the thigh bone concerning which Du Bois +observes: + + We must therefore conclude that the femur [thigh bone] of + _pithecanthropus_ was designed for the same mechanical functions as + that of man; the two articulations [upper and lower joint surfaces] + and the mechanical axis correspond so exactly to the same parts in + man that the law of perfect harmony between form and function of a + bone will necessitate the conclusion that this fossil creature had + the same upright posture as man, and likewise walked on two legs.... + From this it necessarily follows that the creature had the free use + of the upper extremities--now superfluous for walking--and that + these last [the arms and hands] were no doubt already far advanced + in the line of differentiation, which developed them in mankind + into tools and organs of touch.... From a study of the femur and + the skull, it follows with certainty that this fossil cannot be + classified as a simian ... and as with the skull so with the femur + the differences that separate _pithecanthropus_ from man are less + than those distinguishing it from the highest anthropoid [great + ape].... Although far advanced in the course of differentiation this + Pleistocene [Age of Man] form had not yet attained to the human type. + _Pithecanthropus erectus_ is the transition form between man and the + anthropoids which the laws of evolution teach us must have existed; + he is the ancestor of man. + +More extended study of the brain of this ancient fossil creature shows +that he was in reality human. This man did, however, retain so much +that was ape-like in his make-up that it is difficult to agree with Du +Bois in his view that _pithecanthropus_ was a direct human ancestor. +He was, of course, able to walk upon both feet much like his modern +successors. It also seems probable that in stature this primitive man +was not greatly inferior to the human races of the present. It is +likely that he employed his hands in the use of weapons and certain +crude implements. It also seems probable that he depended upon very +primitive means for protecting himself against the numerous enemies +that beset his path and lay in wait about his camping places. His time +doubtless was fully taken up by the arduous task of gaining sustenance +for himself. So busy was he in these obligatory pursuits that he had +little opportunity for developing industries or cultural activities. +This human creature with his ape-like appearance was closely related +to many beast-like contemporaries in the animal kingdom. He managed to +hold his position among them only by a narrow margin of superiority. +His ascendancy was derived from a dawning ingenuity, which enabled +him to equalize the struggle by the cunning of his hand. He took +advantage of primitive shrewdness and contrivance to outwit his natural +antagonists that far excelled him in power and speed. + +However manlike _pithecanthropus_ may have been in respect to the +posture of his body and the general character of his locomotion, it is +certain that he was much below any of the known races of man in his +brain power. His face and head each bore a closer resemblance to the +ape than to man. His brain indicates that he had probably acquired some +mode of speech, primitive no doubt, yet sufficient for the purposes +of simple human communication. It is likewise probable that he lived +in tribes and, being gregarious, had learned some of the advantages +accruing from community life. He may have had some crude notion at +least of the division of labour and its compensations in sharing the +results. + + +_Dawn Man of England_ + +From certain flints, which seem to have many features indicating their +use as instruments, Professor Osborn believes that there were primitive +men living in England at a time earlier even than that assigned to the +ape man of Java. These prehistoric people are called “Subcrag Dawn +men.” It is his opinion that they made use of certain flint instruments +called “rostro-carinates.” Dr. Osborn, believing that these primitive +people are close to the beginning of the human race, places their +origin in the Pliocene, 1,300,000 years ago. In consequence of the +discovery of certain somewhat different flint instruments, he is of +the opinion also that the Subcrag men were followed at a little later +period by the Foxhall Dawn men (antiquity about 1,200,000 years). +Disputes about these early prehistoric Englishmen arise from the +fact that no actual human remains of them have yet been found. This, +fortunately, is not the case with the now famous English Dawn man of +Piltdown, attributed by Professor Osborn and other authorities to the +last part of the Pliocene (a little over a million years ago). Piltdown +is a town in the weald of Sussex not many miles from the English +Channel, between two branches of the Ouse River. To the east of it is +the plateau of Kent upon which have been found many flints of earliest +prehistoric times. It was at Piltdown that the most famous of English +Dawn men was discovered by Mr. Charles Dawson. The fossilized remnants +consisted of a number of fragments of this extinct man’s skull. Because +of the fragmentary condition of this fossil, it was necessary to give +each piece its proper relation to the head in order to reconstruct +the skull. A reconstruction of the Piltdown skull was first presented +to the Geological Society of London, in December, 1912, by Sir A. +Smith-Woodward of the British Museum, and its discoverer, Mr. Charles +Dawson. The announcement of this remarkable discovery deeply stirred +the interest of scientific circles. An unknown phase of the early +human existence was about to be revealed. The reconstructed skull as +pieced together impressed all who saw it as a strange blend of ape and +man. It seemed that the missing link for which the early followers of +Darwin had ardently searched was at length forthcoming. But whether +this was the long sought-for missing link or not, the Piltdown strata +in Sussex told of a race of human beings who inhabited England long +before history had made its feeblest beginnings. Dr. Smith-Woodward +believed that the Piltdown fossil dated back to the early part of +the Pleistocene period, but Sir Arthur Keith and Professor Osborn +now advocate an antiquity far more remote going back to some portion +of the Pliocene. Although it is impossible to be more exact in these +estimations of prehistoric time, it is clear that a very primitive +race of men lived in England long before Cæsar’s invasions; in fact, +ages before the ancient Britons claimed the land that was to produce +many of the most brilliant lights of history. By some the Piltdown man +is regarded as the direct ancestor of modern races; by others he is +held to be an independent branch of the human family of quite unknown +affiliations. + + +_Neanderthal Man_ + +Some time early in the Pleistocene, variously estimated from 800,000 to +900,000 years ago, another race of man made its appearance in Europe. +This was the Heidelberg race (_Homo Heidelbergensis_). These people +manifested many traits distinctly more human than the ape man. It is +believed from the implements found in the neighbourhood of his fossil +remains that the Heidelberg man made use of crude implements both of +wood and stone. This man, although he became extinct before human +progress had made great advances, appears to have been the ancestor +of the Neanderthal race (_Homo Neanderthalensis_). This latter is the +third race of prehistoric men recognized up to the present time. Much +more than all others who had gone before him, Neanderthal man has left +traces of himself. Many of these relics are the stone implements that +he employed. From these implements it is evident that the organization +of his life had made long strides in the direction of his more modern +successors. His advances in industry and in cultural development laid +the foundation for all the stages that progressively evolved as the +human race rose through the Old Stone Age. Yet the fate of Neanderthal +man was not unlike that of other prehistoric men. In time he also +became extinct. His disappearance occurred about fifty thousand years +ago, when a fourth and even greater race of primitive men came into +Europe. These were the Cromagnons. After they had completely replaced +the Neanderthals they flourished for a long time, in the end to be +replaced by the races of Neolithic men which continued dominant up to +the time when man gained mastery over the metals. + +It seems clear, then, that the earliest human beings began as simple, +nomadic hunters. After the passage of great intervals of time and +an actual succession of races, men acquired the crude essentials of +manufacture and then gradually, as in the Cromagnon period, developed +the dexterity and æsthetic sense of the artist. Finally, in the New +Stone Age, they learned the practices of agriculture. + +The past of prehistoric man has been subdivided into periods +characterized by the presence of implements employed in his several +activities. In general, these periods bear the name of French stations +or towns near which the discoveries of the implements have been made. +French archæologists have so successfully devoted themselves to the +efforts of classifying the flint implements that they have established +a chronological order in the development of human progress during the +long periods of man’s prehistoric existence. + + +_The Old Stone Age_ + +Man’s first great epoch on earth was the Old Stone Age (Paleolithic, +900,000 years ago). In this era, which began at some time in the first +interglacial period, the only implements were devised from flint or +stones of other kind, from wood, carved ivory, and bone. The Old Stone +Age was followed by the Neolithic (New Stone Age), which began in +postglacial times and rapidly led up to the thresholds of history, +through the Bronze and Iron ages. + +Long before the Old Stone Age it is probable that man was at work in +the slow development of industries that later were to assume great +importance. Hunting was the great incentive out of which all of +his early industries were evolved. Little is known of his cultural +development, although it seems fairly clear that the Subcrag Dawn +men used certain implements called rostro-carinates, while the Dawn +men of Foxhall and Piltdown employed very primitive implements known +as eoliths. These were so crude in appearance that they are looked +upon by many as merely accidental forms. With such simple and limited +instruments, man’s struggle for existence in these earliest days must +have been most severe. Even at the time when the Old Stone Age began, +the primitive flint implements manifested considerable development. +For example, in the Pre-Chellean cultural stage (beginning 700,000 +years ago), the chase is represented almost exclusively by a simple +flint knife. This knife, although extremely crude, in conjunction with +other equally crude combinations of stone and stick, gave man a slight +balance of power over other animals inhabiting the field and forest as +his competitors. His simple equipment furnished the means to gain his +daily food, and to establish that footing by which he rose step by step. + +War in this period was not among man’s highly organized pastimes. +He appears to have had no implements for warlike pursuits. He had, +however, invented certain instruments for industrial and domestic +purposes, such as a flint scraper, a planing tool, a drill, and a stone +hammer. Nothing among his primitive equipments appears to have answered +the purposes of art or artistic production. + +In this early Pre-Chellean period, man was a vagrant hunter. He +lived without the protection of habitation and was thus exposed to +the devastations of the great meat-eating animals that followed his +wanderings. He had not acquired sufficient constructive ingenuity to +protect himself against these dreaded marauders. They stalked him in +his marches by day and lay in wait on the outer edges of his camps +to find him an easy prey when he slept at night. The less fortunate +members of his tribes were within easy reach of these night prowlers +that waited only for darkness to help them in the capture of their +human quarry. Man’s slow imagination required ages to show him that he +held in his own hands the power to subjugate the beasts of prey. For a +long time he struggled on this low level of intelligence. He lived a +hand-to-mouth existence, passing his days like other animals, getting +his food supply as he dared, and protecting himself as best he could. +Doubtless some critical occurrence like the discovery of fire and its +uses may have furnished a new incentive for his advance. Some great +change in climate with increasing cold may have stimulated him to more +vigorous exertion, may have forced him to become a more persistent +hunter of animals, both for their meat and the warmth to be had from +their protecting skins. Long winter seasons when game was scarce may +also have taught the wisdom of storing his supply of provisions and +thus aroused in his imagination some conception of the advantages in +thought for the future. Living along with him was an imposing host +of other mammals. Among them were the lion, the wolf, the cave bear, +the deer, and the wild boar. Over the plains roamed the Etruscan +rhinoceros, the Mosbach horse, and the ancient elephant. Following +this game he wandered from station to station, always living near the +course of the great rivers, but showing little tendency to establish a +permanent abode. A restless migrant, he was moved by the dictates of +the seasons almost as instinctively as the migratory birds and beasts. +He had not learned the secrets which later enabled him to stand +against the severe vicissitudes of climate. The idea which gave him +that self-assurance to stake out his own claim, to assert his right to +his own angle of earth, was still in embryonic state. + + +_Neanderthal Progress_ + +The foundations of that possessive sense destined to become the chief +characteristic of the human race and at length the ruling passion of +humanity had as yet been laid down only in their simplest form. It +was Neanderthal man who introduced the first real advances over this +primitive level of life. In the Chellean cultural period (500,000 +years ago), even more in the Acheulean period (400,000 years ago), +his race developed rapidly. His progress is shown by a great increase +and considerable refinement in all of the small implements which he +employed. + +He now developed a chisel or adze-like tool for shaping his wooden +implements. He made flint points to form darts and spear heads to +aid him in the chase. But for all these advances, it was not until +Neanderthal man passed into his wonderful Mousterian stage of culture, +about 300,000 years ago, that the human race took a most decisive step +forward. This step was in every sense critical and epoch-making. It +may also be looked upon as a highly profitable step. The effects of it +have made themselves felt with increasing force upon all the subsequent +development of the human race. It was a new departure that, taken so +long ago, actually led the Neanderthal man to the threshold of an +idea in many ways quite original. Ultimately the expansion of this +idea was to become one of the keystones of all social organization. It +may indeed be regarded as the fundamental principle in the upbuilding +of human society. This notable step forward gave the Mousterian man +the first real conception of property holding. It implanted in his +mind that germ out of which grew the rights of possession. This was an +idea which was handed down by him as an heirloom to all the remainder +of his race, and to all other races of mankind. The conception of +property holding developed from the fact that the Neanderthal man in +Mousterian times became a cave dweller. He sought shelter from the +elements in these rude dwellings fashioned by nature. Why he had not +availed himself of these shelters long before is not difficult to +understand. The caves which he might have found to his liking were +already inhabited by dangerous tenants, such as the cave lion, the +leopard, the hyena, the wolf, the great cave bear, and perhaps even +the dread Machærodus or sabre-toothed tiger. All of these were his +natural enemies. For the most part they had been successful enemies. +Man had scarcely dared to dispute the right of way with them, far +less the right of possession. Through all his long periods of upward +progress, he had not yet learned the means by which he could contend +with these beasts of prey on anything like an equal footing. They took +from him at will and his retaliation at best was feeble. They, rather +than he, were the real masters of the situation. This state of affairs +was bound to continue until some critical discovery revealed a new +instrument whose deadliness placed in human hands a supremacy over +these creatures. Some strategy, some modification of the old flint +instruments, perhaps some new combination of them with fire, at length +gave Neanderthal man the needed advantage and then he drove the hostile +beasts out of the caves. In time he established there his own dwelling +places, and there proclaimed his inalienable right of possession. Such +a hazardous undertaking undoubtedly required a hardy courage and an +unwavering persistency. Yet a hard-fought contest of this kind could +not fail to have a marked influence on the final outcome. Once man had +gained the right of ownership, all of the struggles incident to it +served to emphasize his final sense of possession. This triumph did +much to stimulate human desire for gain. It seems fairly clear that +from it arose the incentives of conquest. Since Mousterian times man +has expended much of his energy in exploiting this new advantage. He +has made laws to justify and regulate it. The rights of possession +have had a dominating influence over all of his economic and political +organizations. Most of his moral code has been built up around these +rights. States and empires have been founded upon them, while the +governing principle in the life of the individual has been the right to +have and to hold. In a word, this newly expanded sense of possession +started by Neanderthal man has become an essential element in all the +achievements of mankind. It has no less been the cause of much woe and +maladjustment in the race. + + +_Mousterian Success and Character_ + +It is difficult to estimate the importance of this contribution to the +development of human progress. We may at least give Mousterian man due +credit for establishing this new assertiveness. He likewise deserves +recognition because this achievement was an outstanding milestone on +the road toward higher humanity. For this reason it is worthy of a +special commemorative date. As chronicled by Professor Osborn, this +memorable occurrence, the beginning of cave dwelling, took place about +300,000 years ago. In more senses than one it was a red-letter day for +humanity. It was especially a red-letter day because of the recurring +bloodshed of innumerable wars destined to arise out of the lust and +greed inspired by this expanded sense of possession. This, however, is +the most unfavourable aspect of the Mousterian’s new idea. He himself +should not be made to appear too black on this score. He was actually a +considerable personage and introduced many other new ways of looking at +life that have been highly advantageous to us all. + +Living in dark caves as he did, especially in the long bleak winters, +as the glacial periods crept down upon him, he must have found much +of mystery in those dim recesses to stimulate his imagination. It is +probable that he became a believer in occult forces of nature, and +perhaps even developed a system of magic. These suppositions become +more probable from the fact that he, for the first time in human +experience, established the custom of burying the dead. The men who +lived before him belonged to what may be called the pre-burial period. +This fact unquestionably accounts in part for the scanty human remains +before Mousterian times. The Neanderthal Mousterian not only buried his +dead but he developed an elaborate burial ceremony. The general nature +of this ceremony is shown by the position of the body and of the limbs +as they were found folded and flexed in the fossilized remains of these +men of the Old Stone Age. With certain primitive people this is still +the custom. Even in the case of some of the ancient Egyptian kings +many personal belongings were buried with the dead. Favourite weapons +of the chase, useful implements of one kind or another, ornaments and +other trinkets presumably dear to the departed ones, have been found +with the skeletons in these Neanderthal sepulchres. Special attention +was given to prevent pressure upon or crushing of the head by means +of placing large flat stones upon either side of it. There are some +indications that even as far back as the Old Stone Age man, as part +of his burial service, deposited certain articles of food beside the +body of the departed. All of these facts clearly reveal that as long +ago as 300,000 years man had acquired his first religious ideas. There +is every suggestion about these burial ceremonies that the Mousterian +cave man believed in another life after death. He appears to have had +a strong conviction that the body was but a temporary container of +some intangible spirit that in its time passed on into another world. +It seems probable that he also believed in the return of the departed +spirit to its earthly habitations, else why did he place food in the +sepulchres? In his crude way of thinking he seems to have had certain +well-fixed ideas of the pursuits and occupations in the life hereafter. +For this reason he left a useful collection of weapons and other +implements close at hand, ready for the spirit that had left the body. +The Mousterian idea of immortality may have been simple, but there is +no doubt that it existed. Whether there was a belief in God or not is +difficult to discern. It is probable, however, that the Mousterian, +like all other primitive people, did have some conception of a supreme +being, and that he had thus laid the foundations of religion. + +It is for these reasons that the cave-dwelling Mousterian man +especially deserves our attention. The features of his face and the +character of his body as reconstructed by scientists make him appear +to be a particularly formidable human being. Everything about him +indicates that he was powerful and aggressive. In a word, he was +a splendid fighting machine with heavy, protruding lower jaw, low +beetling brow, thick and short neck, long and heavy-muscled arms, +short, powerful legs slightly bent at the knees. He was a fierce +and dangerous antagonist; one, from all we know of his history, as +courageous as he was powerful. It is probable that in consequence +of his cave dwelling he had begun to live in fairly large organized +communities. Such life as this had many influences upon his social +activities. It developed his use of language. It stimulated his +interest in industries other than those of the chase. It caused +expansion in his imagination, leading to the establishment of racial +tradition. It produced the spirit of individual competition as well +as the pursuits of tribal rivalry. War up to this time seems to +have been limited very largely to individual encounters. Now for +the first time differences of opinion and controversies between one +community and another were most likely settled by group combat. Here, +therefore, were laid the foundations of war that was to prove one +of the most irresistible and costly of all human indulgences. The +self-assertiveness, which must have resulted from the cave man’s +realization that he had finally gained the upper hand in many details +over the natural world, caused him to change his attitude. Instead +of being a fugitive, he now became a conqueror. It was this positive +self-feeling that gave rise to most of his more expansive ideas. The +multiplication of these ideas easily led him on into the realm of fancy +and brought him many illusory interpretations concerning the workings +of nature. + +During the Mousterian period Neanderthal man did not make many material +changes in the implements used before his time. In some instances +there was a distinct improvement of the old ideas; in others there was +a distinct decline or even suppression of some of the most effective +instruments. The cave man’s aims, however, were considerably modified +by his new mode of life. His sheltered existence lessened his physical +powers to resist disease. The making of clothing from the skins of +animals also grew out of this more sheltered type of life. In the end +it produced a people less accustomed to the elements than those earlier +and hardier races that had lived in the open. The effects of this need +for clothing made themselves felt not only in the industry of producing +garments but quite as much in the production of implements necessary +for such work. Cave dwelling permitted disease and imperfect hygiene to +go their full length in producing inroads upon this great Mousterian +race. The ravages of infection and contagion had better opportunity to +exert their baneful influences. These and other insidious factors were +secretly at work. In course of time the Mousterian culture began to +show signs of a steady deterioration. For some mysterious reason these +men of the Old Stone Age slowly began to lose ground. The prominence +held by the Neanderthal race during lower Palæolithic times was +distinctly on the wane as this period approached its end. + + +_Cromagnon Ascendancy_ + +Finally a profound change came over the inhabitants of western +Europe. For some as yet unknown reason the Neanderthal race entirely +disappeared from the earth. Its place, however, was taken by another +and a greater people, the Cromagnons. Without question this was a +replacement of a lower race by one of much higher development. The +Neanderthal was on a distinctly lower plane than any now existing +human type. The Cromagnon ranks high among the races of mankind in +intellectual attainment and in known capacities for production. +He belongs to the species _Homo sapiens_, that same species of man +which has made modern history. He held sway during the last part of +the Old Stone Age, appearing in Europe about fifty thousand years +ago. Like those races which had gone before him, he passed through +many interesting phases of culture and growth. All of these were +characterized by the development of stone implements, thus making him +still a man of the Old Stone Age. He added many new attainments as a +result of new human capacities. He stands out particularly as the first +artist of mankind, and sets a mark as one of the most splendid examples +of humanity both for his superb physical appearance and for his +remarkable mental qualities. But he, too, like all others who preceded +him, was destined to decline and then to disappear. + +The Cromagnon is interesting to us because he was the probable +conqueror of the great Neanderthal race. What secret power he had +to achieve this conquest, to subdue and destroy these fierce cave +dwellers, is still unknown. It may have been that he brought with him +some new implements for warfare, such as the bow and arrow, and that +he had many other advantages of this kind. In any event, he showed +no quarter to the Neanderthals, whom he seems to have destroyed +completely. He did not even follow the custom of many conquerors, +of intermarrying with the women of the conquered race. No generally +admitted sign of Neanderthal features or characters persists among the +race of men after the last Mousterian days. Beyond question it was +the increased brain power of the Cromagnons which gave them their real +advantages. This opinion is based on the appearance of the large brain +case of this race and the development of the almost modern forehead +and forebrain. In the main, our admiration for the ancient Cromagnon +people depends upon something entirely different from their powers +of conquest. They may have been great as warriors, but they were far +greater as artists. This is the aspect of their lives that interests +and influences us most. + +The Cromagnons were a race that developed somewhere in Asia and +migrated westward into Europe. They came in contact with the +Neanderthals and probably destroyed them. They had no ancestral +connections of any kind with this other race. They possessed a brain +capable of more complex ideas, greater comprehension, more reasoning +powers, a wider, more facile imagination. Still more they were endowed +with a highly artistic sense and were capable of advanced education. +Their society was differentiated along the line of capacity and talent +for work. Their artistic productions as shown in the mural decorations +of their caves were so excellent as to place them among the truly great +achievements of mankind. In the pursuits of industry and domestic life, +the Cromagnons added little in the way of innovation. They adapted and +perfected what the Mousterians had previously used. They did introduce, +however, what no other people had ever employed; namely, tools and +implements for sculpture and engraving. These tools in the main were +small and delicate instruments made of flint. Among these was a fine +drill, an engraver, an etcher, a carving chisel, a mortar, a hammer +stone, and a polisher. + + +_Cromagnon Cultural Periods_ + +The Cromagnon, like the Neanderthal, passed through certain cultural +phases. Each of these periods lasted many thousands of years and +each of them was much longer than the Christian Era. The first of +these cultural steps was the Aurignacian period, in which the great +awakening of artistic enthusiasm occurred. The peak of artistic +devotion, however, came in the Solutrean period, which was the acme +of achievement in the flint industry. Decline set in during the next, +the Magdalenian period, which brought the closing stage of Cromagnon +culture. And then in the Azilian period the last survivors of the +greatest race in the Old Stone Age, grown old in their industries and +feeble in their art, saw the setting of the Cromagnon sun and the +passing of their kind into the darkness. Many changes came about in +Cromagnon industries, due to the influences of trade invasions and new +inventions, but in their art these people showed one continuous and +sustained development. + +The impressive feature about Cromagnon art, especially in the +Aurignacian period, is the absence of that period of infantilism and +crudity almost always observed in the artistic development of primitive +races. The Cromagnon first reveals his artistic effort in a state of +sturdy youth. His art passed directly into a relatively mature stage. +Its treasures preserved in the art galleries of the ancient caves, +comprising remarkable drawings, sculptures, and paintings, fully +warrant the title of “Palæolithic Greeks” conferred upon the Cromagnon. +Indeed, they resemble the Greek and Egyptian artists in many ways. +Like them, the Cromagnon resorted to painting his reliefs whether they +were of the bison, the horse, the deer, or the great mammoths. The +relative simplicity of his technical skill depended upon the employment +of fewest possible lines and boldest of strokes. To his accuracy of +reproduction and his simplicity of style he imparted a third great +quality. This added artistic element, which has made his art live in +a class well up to the standards of later periods, was a feeling of +motion, particularly of locomotion. With this he vividly endowed the +animals carved upon the walls of his cavern, upon bone or ivory. + + +_Motives of Cromagnon Art_ + +It is clear that the Cromagnons were cave dwellers like the +Neanderthals, but they also depended largely upon the chase for their +living. Why, then, did they in the dark recesses of their caverns +resort to these remarkable artistic activities? These efforts could +scarcely be meaningless diversions. They must have been more than +pastimes, for hours not devoted to the hunt or combat. Such arduous +pursuits as these surely had some serious and pertinent object in +their lives. Many explanations have been offered for the remarkable +outburst of artistic enthusiasm in Cromagnon times. The one most +generally accepted is that the art of these people was a part of their +hunting magic. In the history of primitive races it has repeatedly +occurred that drawing and design have a special significance in the +actual maintenance of life. For example, the Australians draw pictures +of animals they use for food. Sitting on the ground about these +pictures, they perform certain ceremonies which they believe will +insure a plentiful supply of the food they need. The American Indians +are in the habit of carving images of animals. They also draw the +signs representing rain. In the presence of these emblems they make +incantations and believe that by this means they will secure abundant +harvest and complete success in their hunting expeditions. Images and +pictures act as a sort of magic talisman by means of which to exercise +an influence over those animals which serve for food. + +But we do not need to go back into the pre-history of the Old Stone +Age, or to the superstitions of people still in a primitive stage. Not +so long ago the picture of a man was supposed to represent his spirit, +and the possessor of such a picture could exert a magic power over his +person. Only a few centuries ago learned judges condemned to death men +and women on the evidence that they possessed images or pictures of +people they were accused of bewitching. Until quite recently there were +certain sorcerers and magicians in Sicily who for a price would destroy +a hated enemy by the simple executionary method of sticking pins into a +wax image of this undesirable person. + +It seems to require no further explanation to understand the pictorial +efforts of the Australian natives and American Indians. Like them, +the Cromagnons drew for the most part the animals which they employed +for food. This may not in all respects be a satisfactory answer to +the question: Why did man of the Old Stone Age resort to art? It is, +however, a good working theory. It shows a real motive for his efforts +in this direction. To his mind, all of his works of art assured him +some peculiar magical control over the animal life that was necessary +for his living and well-being. + + +_Men of the New Stone Age_ + +The fate of the Cromagnon race was no exception to what had gone before +or what would follow many times thereafter. Race after race, nation +after nation, rose and became master, declined and passed into final +extinction. As the day of Cromagnon ascendancy waned a new race invaded +western Europe. The Old Stone Age came to its end approximately ten +thousand years ago with the advent of the more vigorous Neolithic (New +Stone Age) man. He developed a great innovation in manufacturing his +implements, making his instruments better and more useful by polishing +the stone. Neolithic man was far more practical and thoroughly +utilitarian than his predecessors in the Old Stone Age. He introduced +many economic advantages and substituted the benefits of applied +science for the delusions of magic and sorcery. The man of the New +Stone Age, unlike his Cromagnon predecessor, did not alone pray for +his crops. He tilled the soil and planted seed. Perhaps he believed +in a magic ritual for his hunting expeditions, but to make his food +supply as secure as possible, he domesticated many animals that he +liked to eat. He was unwilling to depend solely upon hunting magic and +art sorcery. He had discovered the true magic of agriculture and sought +to control nature by the toil of his hands rather than by mysterious +incantations and pictorial art. As a farmer and a cattle raiser he +required a permanent home, and in consequence the New Stone Age gave a +fresh impulse to the upbuilding of man’s possessive sense. Neolithic +man became a land holder, and this advance was a long, provocative step +in the direction of modern humanity. Because of it man had to learn +new ways and means of defending his claim and of asserting his right. +Very quickly this new assertiveness led to the more sanguinary ages +of Bronze and Iron with their effective equipments for offense and +defense. Its influences finally reached historical times. Ultimately +these more aggressive tendencies created all of the armed camps that we +are pleased to call civilization, ancient, mediæval, and modern. + +At the close of the New Stone Age all of the direct ancestors of modern +European races were established in Europe. During the Bronze Age man +rapidly learned those new capacities which enabled him to make a +permanent record of himself, and thus he entered upon his real historic +period. Some authorities set the beginning of this period only so far +back as the beginning of the Egyptian calendar. In round numbers this +is five or six thousand years ago. + +The dawn of history was followed by a procession of great events which +began in the early Egyptian dynasties. The development of Pharaonic +art and culture, the regal splendours of Babylonia and Chaldea, the +incomparable achievements of Greece and Rome, followed in rapid +succession. Each of these civilizations in its turn contributed to the +development of the race. Then came the long eclipse of the Dark Ages in +mediæval times, and at length the brilliant light of the Renaissance, +the illuminating influences of which have been carried forward in that +steady progress of material accomplishments characteristic of modern +times. + +A brief review of man’s progress in his prehistoric existence shows the +following races in his advancement, known by fossil remains: + + 1. Ape man of Java (_Pithecanthropus erectus_). Professor Osborn + prefers to consider him the Dawn man of Trinil. Probable antiquity + about one million years. Probably employed crude stone implements and + was a nomadic hunter. Had a poorly developed human brain; nothing + known of his cultural development. Chief contributions to human + progress: human frontal lobe, human speech, and a complete erect + posture. + + 2. Dawn man of Piltdown, England (_Eoanthropus dawsoni_). Antiquity + over a million years, probably employed crude instruments known + as eoliths and thus belonged to the Dawn Stone Age. Had a fairly + well-developed human brain. Was a migrant hunter. Nothing known + concerning his cultural development. Chief contribution to human + progress: further development of the brain. + + 3. Heidelberg man of Germany (_Paleoanthropus_). Antiquity about + 800,000 years. Fairly well-developed human brain and frontal lobe. + Probably employed crude stone implements. Little known of his + cultural phases. Chief contribution to human progress: first man of + the Old Stone Age and probable progenitor of the Neanderthal race. + + 4. Neanderthal man (_Homo primogenius_). Probable antiquity 600,000 + years. A well-developed human brain and frontal lobe. Made and + improved many flint implements. Hunter and cave dweller. Had definite + cultural periods known as the Chellean, Acheulean, and Mousterian. + Chief contributions to human progress: established idea of permanent + abode, became dominant over other animals of the earth, introduced + human burial, laid the foundations of religion. Founder of human + assertiveness and supremacy. + + 5. Cromagnon man (_Homo sapiens_). Probable antiquity 50,000 years. + Well-developed human brain and frontal lobe of modern type. Hunter + and artist, employed somewhat refined flint implements of the Old + Stone Age. Had definite cultural periods known as the Aurignacian, + Solutrean, Magdalenian, and Azilian. Chief contribution to human + progress: the conqueror of Neanderthal man; the world’s first great + artist. The founder and introducer of art. + + 6. Neolithic man (_Homo sapiens_). Probable antiquity 10,000 years. + Human brain and frontal lobe of modern type. Employed polished flint + implements of a highly developed kind. Was a hunter, herdsman, + and farmer. Chief contributions to human progress: introduction + of agriculture, culinary art, domestication of animals; also + establishment of more permanent abode. + + 7. Bronze and Iron Age men (_Homo sapiens_). Probable antiquity 7,000 + years. Human brain and frontal lobe of modern type. Used implements + made of bronze and iron. Chief contribution to human progress: + introduction of the metals for human utility. + +In addition to these prehistoric races of men, certain other early +members of our family have been recognized in the latter part of the +Pliocene and early part of the Pleistocene. These races include the +Subcrag and the Foxhall Dawn men who appear to have employed the +rostro-carinate flints. Still another race was the Cromerians, who made +and used the giant flints found embedded in the cliffs of Cromer. + +Prehistoric man is thus gradually emerging from his long obscurity. +His skeletal form is known from more than 350 specimens of his fossil +remains. In Java, in central Asia, in Rhodesia, central Africa, in +Gibraltar, in the Island of Jersey, in France, in Germany, in England, +in Austria, and in Galilee, Palestine, these remains have been found. + +All phases of man’s early existence are important to our modern thought +and development. As the curtain of the past is lifted to reveal the +long, prehistoric vista of human existence, it is possible to sense the +vast distance that man has come since his journey began. It is also +possible to see how he has made his way and why he has progressed. From +its earliest appearance on earth the race has grown in humanity as the +brain expanded. In man’s first struggles brain power endowed him with a +capacity to develop and to hand down certain cultural activities. The +earliest instruments that he fashioned gave rise to an uninterrupted +stream of human achievements which has passed on as the main current +of culture and knowledge. It was this capacity for progressive and +racial learning that distinguished the human brain. Estimated by his +accomplishments, it seems necessary to assume the existence in man of +some special power different from all other living creatures. This +distinguishing endowment is variously called the soul, the psyche, the +spirit of man, or human genius. Its name may be immaterial, but its +source is the secret of our supremacy. If we acquired this power as the +divine gift of a creative miracle, that is one thing. If we earned it +through a long and tedious process of evolution, that is even a more +promising and an altogether different thing. + + + + +CHAPTER IV + +EDEN OR EVOLUTION + +GENESIS AND THE ORIGIN OF SPECIES + + +_Early Beliefs in Creation_ + +Although we may entirely reject the evidence of man’s presence on +earth long before the dawn of history, even so there still remains a +perplexing question that must be answered. What was man’s origin? It +is surprising how many people have attempted to solve this troublesome +problem. It seems to be one of the first questions that primitive man +tried to answer for himself when he began his earliest speculations. +He was naturally anxious to know who made the land and the water and +the sky and all that is in them. He was especially interested, when he +thought about such things, in deciding how he came to be what he was +himself. And so, from earliest times, beliefs concerning the beginning +of things have sprung up all over the world. They constitute a mass of +speculation, which is called cosmogony (beliefs or theories about the +creation of the universe). Only a few races or tribes of mankind have +failed to indulge in speculations leading to such beliefs. Appearing as +they do in the infancy or early life of a race, these beliefs must be +the fruit of the primitive human mind. In peoples who have failed to +progress and have always remained primitive, such beliefs, like many +other traits and customs, continue for generations almost unchanged. +Sometimes they become an important part of the religion of the race. If +they are looked upon less seriously they form themes for folklore. + +This searching question about man’s origin has always been present and +is, in fact, still with us. In times gone by, when man was primitive, +or at least more primitive than he is to-day, he tried to answer the +question as best he could. He was hampered by lack of facts because +his knowledge and understanding of his own surroundings were limited. +His racial experience in the world had yet been too brief for him to +do more than see the great generalities of nature. At best he could +merely surmise the truth of the universe. He had neither the training, +the methods, nor the instruments necessary to disclose the intimate +details upon which reasonable theories might be based. Being so largely +destitute of facts, he relied upon intuition or drew heavily upon his +imagination. It is a matter of wonder that his beliefs often took such +noble form. + +Not infrequently a common central theme runs through the beliefs of +primitive people, even though they may belong to different races and +are separated from each other by long distances. Such, for example, is +the belief in the manlike appearance of the Supreme Being held by the +Hebrews, Greeks, Romans, and many other ancient civilizations. Early +ideas concerning _creation_ illustrate this common or central theme +still more vividly. Doubtless the conception of creation has its +supreme expression in the opening chapters of Genesis in the Hebrew +Testament. But other primitive people had exactly the same ideas about +creation and the origin of man. This way of solving the problem must +have been one of the inherent tendencies of the human mind in its +earliest beginnings. Isolated peoples in far-distant parts of the earth +could not have shared such similar ideas as a result of racial contacts +or propinquity. Time and distance set them widely apart. The similarity +might be ascribed to traditions handed down from a common stock. In +any event, an identical theme runs through the creation story of many +different peoples. The most effective record of this theme is given in +Genesis, especially in the first chapter, the King James version of +which is accepted by many as the highest literary mark ever set by the +English language. It is of particular interest for us to follow the +sequence of events in this incomparable chapter which depicts creation +with such grandeur that it may well be called inspired. + + +_Early Accounts of Creation_ + +According to this record, creation proceeded as a succession of +separate miracles. First came the miracle creating heaven and earth, +then the creation of light, of the firmament, of the earth set apart +from the waters, of vegetation upon the earth, of the sun, moon, +and stars, of fish and fowl, of beasts and cattle and all creeping +things, of man and woman together in the image and likeness of the +Creator. The second chapter of Genesis repeats the story of creation, +but this time in a minor key, with certain striking differences and +discrepancies. The grandeur of the original description and its +sublime intuition are missing. The master mind which conceived it has +obviously been replaced by one at once much more naïve and manifesting +a thoroughly parochial interest in the affairs and frailties of +humankind. This second narration largely reverses the original order +given to creation. By it man is created before all other animals and +woman last of all. This account produces man from the dust of the +ground, into which the Creator breathes the breath of life and gives +him a living soul, while the rib taken from man is used to create +woman. The discrepancies in the two accounts are obvious at once. To +explain them the second chapter is attributed to a very early writer +(Jehovistic document). The first chapter is ascribed to a much later +writing (Priestly document) made during the Hebrew captivity in Egypt. + +Earlier than this Biblical record was the Babylonian idea of creation. +These people also conceived that man was molded out of clay. According +to the Babylonian version of creation, the god Bel cut off his own +head, and the other gods, catching the flowing blood, mixed it with +the dust of the earth, and from this bloody paste molded the forms of +men. The Babylonians believed that men were wise because their mortal +clay was thus tempered with divine blood. According to the Egyptians, +the father of the gods molded men out of clay on his potter’s wheel. +A Greek explanation of man’s origin contains the same idea, in that +Prometheus is said to have molded the first men out of clay at Panopeus +in Phocis. These naïve conceptions about the origin of mankind, +common to the Hebrew, the Babylonian, the Egyptian, and the Greek, +were doubtless handed down to these ancient civilized people by their +savage or barbarous forefathers. Legends of creation of exactly this +kind are current among savages and barbarians of the present day. It +is particularly interesting to note the different forms in which this +story has made its appearance in many distant places of the earth. + + +_Creation Beliefs of Barbarous People_ + +The Australian blacks, near Melbourne, held that the Creator cut +large sheets of bark with his big knife. He placed on one of these a +mass of clay and prepared it with his knife until it had the proper +consistency. Then he set a portion of the clay on another piece of +bark and fashioned it in human form, making first the legs and then +the trunk and arms and finally the head. Having finished his molding, +he took stringy bark from the eucalyptus tree, made hair of it, and +attached it to the heads of his models. When all was finished he blew +his breath into the mouths and noses and navels of these clay men until +they rose and spoke as full-grown human beings. + +In New Zealand the Maoris believed that a certain god took red +riverside clay, kneaded it with his own blood into a likeness of +himself, with eyes, legs, and arms exactly similar to his own. When +this model was finished he breathed into it the breath of life through +its mouth and nostrils, with the result that the clay man at once came +to life and sneezed. + +Among the Tahiti there is a tradition that the first man and woman were +made by the chief god, who created them out of red earth. In Netherland +Island, one of the Ellice Islands, a great deity is supposed to have +made models of man and woman out of the earth and brought them to life +by lifting them up. Similar in general conception is the tradition of +creation among the Pelew Islanders who believe that certain of their +deities made man and woman out of clay by kneading it with the blood +of various animals. This feature is a new detail and somewhat of a +departure from the general story. It shows, moreover, the interest +which these primitive people had in explaining the different behaviour +of their fellow men. Thus they believed that the characters of these +first men as well as their descendants were due to the characteristic +traits of the animal whose blood was mingled with the clay. Men, for +instance, who had rats’ blood in their clay were thieves. Those who had +serpents’ blood were sneaks and informers. Those who were vitalized by +cocks’ blood were brave and daring. + +According to a Melanesian legend in one of the Banks Islands, the great +hero Qat molded men from red clay taken from the marshy riverside. At +first he made men and pigs to appear alike, but subsequently he forced +the pigs to go upon all fours and caused men to walk upright. This +distinction indicates man’s early recognition of the subtle meanings of +the erect posture. Qat also constructed a female out of flexible twigs. +Finally she smiled at him, and by this unfailing sign of feminine +allurement he immediately recognized her as the first woman. + +Inhabitants of the Kei Islands believe that their ancestors were +fashioned out of clay by the supreme god who breathed the breath of +life into the clay models. The Dyaks of British Borneo claim that the +first man was made by two birds. After several failures in attempting +to hew him out of rock they at length molded him out of damp clay and +infused into his veins the red gum of the Kumpang tree. When they +called him he answered, and they gave him a name which in the Dyak +tongue means “molded earth.” + +In India also the same kind of legend explains man’s origin. The Kumis +who inhabit the hill tracts in eastern India believe that a powerful +god made the world and the trees and the creeping things first. After +this he made a man and a woman, shaping their bodies from clay. When +he had finished his work a great snake came while the god was sleeping +and devoured the two images. This occurred several times, so that the +deity was much perplexed. Feeling that after his day’s work he needed +a good night’s sleep, it was impossible for him to sit up to protect +his handiwork. At length he conceived the plan of making a dog out of +clay before he created his next models of man and woman. This device +solved the problem in a satisfactory manner. The god was now able to +sleep in peace after his hard work of modelling human beings, since the +dog, watching over them, would bark and frighten away the destructive +serpent. To this day the Kumis believe this is the reason why dogs howl +when a man is dying. + +Africa has similar legends about the creation of mankind. Many of the +natives on the White Nile believe that men were modelled out of clay. +They even go so far as to explain the different complexions of various +races by the differently coloured clay out of which they are molded. +Their great creator, wandering about the world, found pure white earth +or sand and from this he fashioned the white man. Returning to Egypt he +molded red and brown men from the mud of the Nile. Finally, coming upon +black earth far in the depths of Africa, he created black men. + +The story of man’s creation out of clay also occurs in America among +the Eskimos and the Indians from Alaska to Paraguay. Many of the +Eskimos have the belief that a certain spirit made a man of clay. Then +having set him upon the shore to dry he breathed into him and gave him +life. Certain Indians of California conceive of an all-powerful being +who created man out of a deposit of clay which he found on the shores +of a lake. From this clay he made both male and female, and the Indians +of the present day are descended from this original clay man and woman. + +The Mayas in Central America believe that their gods first made men out +of clay, but that these clay models lacked vitality because they were +dissolved by water. Then the gods created man out of the wood of one +tree and the woman from the sap of another. Unfortunately these human +beings could neither move nor propagate their kind, and for this reason +the gods caused a shower of pitch to produce a flood, which destroyed +this wooden race. A few of them survived, however, and from them are +descended the small monkeys. The Maya gods at last created four perfect +men out of yellow and white maize, and, wishing to confer the greatest +boon, while these four perfect beings slept, four women were created +for them. + + +_Primitive Ideas Foreshadowing Evolution_ + +It is interesting also to find that all savage people did not believe +in the legend that ascribed the origin of man to clay models or to +effigies made by some supreme being. Many primitive races appear to +have preferred the theory of evolution to this other idea of creation. +In any event, even if they did not fully recognize the nature of their +belief, their idea was that man evolved from some lower form of animal +life. The particular form of animal from which this evolution started +varied considerably with the local colour, with the character and with +the opportunities of different people. + +Some California Indians believe that they are descended from coyotes. +In their early stages of evolution all members of their tribe walked on +all fours. Slowly they acquired some of the features of human beings, +one toe or one finger at a time. Then came an eye or an ear, until at +length these animals grew to be perfect human beings by losing their +tails. This loss, which was regarded as deplorable, came from the habit +of sitting upright. + +The Iroquois, belonging to one important clan, hold that they are the +descendants of mud turtles that formerly inhabited a certain large +pool in their territories. The Choctaw Indians believe that they +were descended from crayfish, while throughout the Osage Indians it +is generally understood that their ancestors were a male snail and a +female beaver. A great flood carried the snail down the Missouri River, +leaving him upon a bank, where the sun ripened him into a man. In time +he met and married a beaver maid, and these two were the ancestors of +the Osages. The Delaware Indians call the rattlesnake their grandfather +and would on no account destroy one of these serpents. + +Certain Indians of Peru claim to be descended from the puma or American +lion, and this animal is worshipped as their god. Some natives of East +Africa look upon the hyena as one of their ancestors. The death of this +animal is mourned by the whole people with great funereal ceremony. On +the Gold Coast of West Africa certain tribes believe that they were +descended from the horse mackerel. + +Natives of Borneo think that the first man and woman were born from a +tree which had become fertilized by a creeping vine that waved to and +fro in the wind. Some of the primitive inhabitants in the northeastern +extremity of Celebes believe that they are descended from apes and +that the parent stock of these animals still inhabits the woods. The +aborigines of western Australia considered that their ancestors were +swans, ducks, or various other kinds of water birds, which were later +transformed into men. + +All of these illustrations of the creation idea among primitive people +show that man has held at least two widely different views about his +own origin. One of these is the idea of separate miraculous creation; +the other corresponds to or foreshadows the theory of evolution. In +accordance with the view of separate creation, a god or a tribal hero +was the great creator who fashioned the first members of the race +in their present form. According to the other view, man was evolved +from lower forms of animals, or even from vegetable life. These two +viewpoints of man’s origin still divide the peoples of the world. It +is probably true, as Sir James Frazer has said, that “by weighing one +consensus against the other, with Genesis in the one scale and the +Origin of Species in the other, it might be found, when the scales +were finally trimmed, that the balance hung even between creation and +evolution.” + +The development of the evolutionary theory among civilized people has a +long history. This theory has already passed through many interesting +phases. Doubtless other equally interesting phases lie before it. At +present there are many who still believe that Darwin was the originator +of the evolutionary idea. This belief is in no sense true. The origin +of the doctrine long antedates Darwin’s time. It may be traced back to +the age when the human race first began to think clearly. Like many +other things of high cultural value, it had its earliest recognizable +beginnings in the Greek period--in those days when man sought to gain +an intelligent understanding of himself and the world in which he lived. + + +_Growth of the Evolutionary Theory_ + +The basic conception of evolution is as old as Empedocles (450 B. C.). +Aristotle (384-322 B. C.) was the originator of the theory of animal +descent, which he formulated with remarkable clearness. A strong +inhibiting influence fell upon this conception of life as a result of +mediæval scholasticism. This influence restrained further developments +until the subject was again reopened in the Eighteenth Century. The +works of Leibnitz and Buffon (1707-1788) reawakened interest in this +problem. Modern constructive efforts to formulate the theory of +evolution did not begin, however, until the early Nineteenth Century. +By a strange coincidence, the real founding of this theory occurred in +the year of Darwin’s birth, 1809. Up to this time, with few exceptions, +it was thought that man’s body was the result of special creation. Some +savage people, as we have seen, have believed that man was derived from +lower animals. But this belief was only a fantastic forerunner of the +evolutionary concept. The birthplace of the theory was in Paris. It +may appear strange that such a doctrine did not originate in the great +schools of learning, and that it first saw the light in the quiet, +out-of-the-way location of the Museum of Natural History. The names +of three scientific immortals are associated with this revolutionary +conception of the animal kingdom. All three of these distinguished men +lived at the same time, worked together at the same place, and together +profoundly influenced our modern views of man’s place in nature. + +The most noted of this famous trio in his own day was Cuvier +(1769-1832). He was a professor of comparative anatomy and though only +forty years of age was accumulating the material for his epoch-making +work, _Ossements Fossiles_. This work was to show conclusively that the +great ages of time, filled with multitudes of strange, extinct animals, +had passed over the earth before the dawn of our modern era. Cuvier +believed that each group of these extinct animals represented a series +of separate creations. It was doubtless his energetic and brilliant +insistence upon this point that denied to the French nation the first +place of distinction in advancing the theory of evolution. Although +he held vigorously to the old creative interpretation of life, Cuvier +was in a sense an unconscious promoter of the evolutionary idea. His +recognition of a succession of epochs in the earth’s history and in +the animal inhabitants of the globe was an important step toward the +modern theory. Besides this, his keen powers of observation had enabled +him to discern one of the chief principles underlying evolution. This +principle is known as the law of “correlation of parts.” In consequence +of this law there is a definite relation of one part of the body to +another, as well as a combination of these parts in the habits of the +animal. Thus, horns belong with hoofs, and hoofs are associated with +complicated grinding teeth, which latter in their turn are possessed by +animals having complex stomachs and feeding on plants. + +The second great pioneer in the discovery of life’s true origin was +somewhat younger than Cuvier. This was Geoffroy Saint-Hilaire. He +was intent upon seeking the common plan upon which all animals with +backbones were built. In this way he was laying the foundations of that +broad conception of life which holds that all living things have a +common descent. + +The third of these great French contemporaries was more obscure +than either of his associates in the Museum. In his own period the +public heard and knew little of him. He was a retiring person, but +an indefatigable student. As time passes it is he who stands as the +towering figure of this famous trio. In 1809, when he was already +sixty-five years of age, he made his remarkable contribution to +knowledge. His careful studies of nearly fifty years were then +published in two small volumes entitled _Philosophie Zoologique_. This +was a milestone in human progress. In consequence of this work alone +the name of Jean Baptiste Pierre Lamarck will stand as one of the most +eminent figures of science. From his long and laborious researches he +had reached the conclusion that all living creatures were the outgrowth +of a common tree of life. In this treatise of his there appears the +first clear declaration that man has been evolved from some anthropoid +ancestor like the chimpanzee, and that man’s erect posture has been +derived from one which was ape-like. + + +_The Lamarckian and Darwinian Theories_ + +The Lamarckian theory of evolution holds that progress takes place by +the imperceptible transformation of one species into another through +the efforts of the organism to adapt itself to new conditions. It also +maintains that, by inheritance, the changes thus produced are handed on +from one generation to the next. These changes may be slight, almost +insensible variations produced by the use or disuse of certain parts +and organs. Through their accumulated effects they are capable of +transforming one species into another. The following quotation from +Lamarck’s _Philosophie Zoologique_ (Vol. 1, p. 349) furnishes some of +the more important details in the concept by which he explains the +evolution of man: + + Indeed, if any race of primates (quadrumanes) whatsoever, + particularly the more highly evolved of them, were to lose, either + from force of circumstances or any other cause, the aptitude for tree + climbing and of grasping the branches with their feet, as with their + hands, for security of grip, and if the individuals of this race, + for a series of generations, be obliged to use their feet only in + walking, and cease using their hands as feet; then there is no doubt, + from the evidence produced in the foregoing chapters, that these apes + would finally be transformed into man (bimanes) and that the great + toe would no longer be separated from the other toes like a thumb, + the feet merely serving the purposes of progression. + +Despite the fact that Lamarck was a pioneer he did not, in so far as +the evolution of man is concerned, induce a single anatomist of his +own time or of a succeeding generation to follow in his footsteps. +In this respect his great work remained strangely ineffective. The +more persuasive introduction of the evolutionary theory was made by +an illustrious English naturalist, Charles Darwin. After a somewhat +mediocre university career, for which he received the degree of +Bachelor of Arts, Darwin devoted himself to the natural sciences. In +his early manhood he spent five years on the famous barque _Beagle_ +in which he made a trip around the globe. Twenty-three years later +(1859) he published his renowned _Origin of Species_, which proved to +be one of the most revolutionary books ever written. In an educational +sense, Darwin was far more fortunate than Lamarck. Almost at once he +obtained the ear of the public and started the theory of evolution +on its strenuous course around the world. Twelve years later (1871) +he published his second monumental book, _The Descent of Man_, which +proved to be the most telling step in our modern knowledge of man’s +evolution. These two great books set forth the Darwinian theory. Like +Lamarck, Darwin believed that progress from lower to higher forms of +animal life took place as a result of insensible variations. These +variations were due to what Darwin and one of his contemporaries, +Alfred Russell Wallace, called natural selection. This factor was the +prime and sufficient cause of evolution. Through its operations new +species arose by the selective action of external conditions upon +individual variations. Natural selection, as a law, implies the effects +of those forces which separate living creatures into two groups--those +which survive and those which, being ill equipped to make the struggle +for existence, perish. The selective effects of external conditions +on an organism or its parts operate in such a way that individual +variations or peculiarities of advantage are perpetuated in the race +and thus give rise to the survival of the fittest. Darwin in his +_Descent of Man_ makes clear his opinion of the manner in which natural +selection has operated in human evolution: + + As soon as some ancient member (elsewhere defined as some species + of anthropoid like the chimpanzee) in the great series of the + primates came to be less arboreal, owing to a change in its manner of + procuring subsistence, or to a change in the surrounding conditions, + its habitual manner of progression would have been modified and + thus it would be rendered more strictly quadrupedal or bipedal.... + Man alone has become a biped and we can, I think, partly see how he + has come to assume his erect attitude which forms one of his most + conspicuous characters.... As the progenitors of man became more + and more erect and their hands and arms more and more modified for + prehension and other purposes, with their feet and legs at the same + time transformed for firm support and progression, endless other + changes in structure would have become necessary. The pelvis would + have to be broadened, the spine peculiarly curved, and the head fixed + in an altered position, all which changes have been attained by man. + It is very difficult to decide how far these modifications are the + result of _natural selection_ and how far of the _inherited effects_ + of the increased use of certain parts or of the action of one part on + another. No doubt these means often coöperate. + +Comparing the explanations given by Lamarck and by Darwin it is +clear at once that they have much in common. Both suppose that man +was evolved from a chimpanzee-like anthropoid. Both agree that the +transformation had been initiated by a change from an arboreal to a +terrestrial mode of existence. Both believe that the results of habit +or of function acquired by one generation may be inherited by the next +generation. Darwin made certain important additions to this theory. +He applied the law of natural selection--the tendency of successful +individuals to survive and prosper. He also recognized the effects of +sexual tendencies and perceived that there was a law of correlation of +parts. By this latter mechanism a number of structures were modified at +the same time to suit some particular function of the body. + +Since Darwin’s time, although the general principle involved in the +theory of evolution has been accepted by scientists everywhere, +there has been much discussion concerning specific details of the +evolutionary process. Simultaneously with the conviction that evolution +was a fact in the animal life there arose an eager desire to discover +its underlying causes. Many students of the problem have arrived at +independent explanations of their own. To some the theory of Lamarck +has been considered satisfactory; to others Darwin’s interpretation +is most convincing. Such differences of opinion as do exist among +those who have seriously pursued this matter centre primarily upon the +causes of evolution. For this reason a number of different theories are +recognized to-day. It is probable that these theories do not represent +all of the differing shades of opinion concerning this subject at +present. They may be said, however, to express the high points of +difference. Their chief interest lies in the fact that they indicate +the degree of energy and determination devoted to the solution of +this problem. Recent students of the Darwinian theory have modified +and extended it in such a way as to make the law of natural selection +entirely sufficient to explain evolution. Such students, with Weismann +the most prominent among them, deny the inheritance of acquired +characters. This view is known as the neo-Darwinian theory. + +Lamarck’s original conception was also modified and became the basis of +the neo-Lamarckian theory. This view recognized all of Lamarck’s ideas, +including insensible variation, use and disuse of parts, and hereditary +transmission. But it added to these causative factors certain +influences of consciousness and the will, thus introducing an internal +and psychological principle in the evolutionary process. In America +this newer view of Lamarck’s conception has been vigorously upheld by +many naturalists (Cope and Hyatt) who attempted to explain evolution +according to the fundamental laws of growth plus the inherited effects +of use and disuse. + +Explanations such as these seem to lose sight of many influences acting +upon animal life from without and along certain determinate lines. +These influences were highly specific in their character and embraced +definite chemical and physical factors. Their effects were concentrated +upon limited organic areas, such, for example, as the eye, but they +spread to correlated organs like the brain, the muscles, and the bones, +all of which are functionally continuous with the visual apparatus of +vertebrates. Such a spread of modifying influences from a determinate +focus like the eye throughout the entire body caused a widespread +tendency to variation and thus afforded the opportunity for progressive +development. This explanation is known as the Orthogenetic Theory +(Eimer, 1897). + +Still more recently the pendulum has swung away from this extremely +materialistic viewpoint in what is called the Creative Theory of +Evolution (Henri Bergson, 1907). According to this explanation the +variations that bring about evolution from lower to higher forms of +life require some good genius to preserve and collect the effects in +the interest of progress. This presiding genius working from within +is the original impetus of life, the _élan vitale_, or vital impetus +(entelechy), which like some internal perfecting agency passes from +one generation of germs to the next and through the developed organism +bridges the interval between generations. + +Philosophy, with its conception of an internal creative power common +to all life and biology, pinning its faith to physicochemical factors, +have vied with each other in bringing to light the causes of evolution. +Among the latest explanations is the Energy Theory (Henry Fairfield +Osborn, 1918). This interpretation holds that the life of every animal +is due to the action, reaction, and interaction of four types of +energy. The first type arises from chemical elements and compounds +surrounding the animal (inorganic environment). The second is the +energy derived from the body substance of the developing organism +(protoplasm and body chromatin, the chief substance in the nucleus +of body cells). The third source of energy is from the sex cells, +especially those parts of them which contain the hereditary elements +(hereditary chromatin). The fourth type of energy comes from the +living matter surrounding the animal (life environment). Selection and +adaptation are constantly at work upon the reactions of these four +types of energy. Divergence in the form of different animals depends +upon adaptations to special conditions of life as seen, for example, +in the whales and the meat-eaters. Altogether there are twelve major +environments for living, like the plain, the forest, the air, the sea, +which require special adaptations. All life has tended to radiate out +into such habitat zones, and the four types of energy represented by +each living creature have been adjusted to a particular environment. +This spreading out of life into many different zones of existence is a +recognized principle in natural selection (law of adaptive radiation. +Osborn). + +The most recent interpretation is that offered by the Emergent +Theory of Evolution (C. Lloyd Morgan, 1928). Evolution, according to +this explanation, is the name given to the plan of sequence in all +natural events. Orderly sequence presents from time to time something +genuinely new. In the physical world emergence is exemplified by the +advent of each new kind of atom, each new kind of molecule, each new +form of life. Emergence is not the mere addition to or subtraction +from existing properties. It is the appearance of something new and +unpredictable from the combination of properties already in existence. +A true emergence of this kind is produced by the combination of carbon +and sulphur out of which the gaseous carbon bisulphide arises. This gas +is totally different from either sulphur or carbon, its two combining +ingredients. It is something genuinely new and hence an emergent. This +principle affects all spheres of life in such a manner that it is +possible for new characters, new structures, new activities to appear +as emergents from preëxisting elements. Variations and progressive +development may be thus explained as the result of orderly sequence. + +In spite of the differences in opinion among scientists concerning +the evolutionary process, there is an almost unanimous agreement with +regard to the correctness of the general theory of evolution and the +principle underlying it. To attempt a critical estimation of these +several theories would be futile and far removed from our present +purpose. Doubtless each one of them contains some portion of the truth. +It is, however, their large number that is of striking significance, +inasmuch as these theories indicate a widespread, profound, and growing +interest concerning evolution among intelligent people. Whatever their +minor differences, such theories demonstrate a determined effort in the +search for truth and manifest tendencies in thinking which cannot fail +eventually to reshape the intellectual outlook of mankind. + + + + +CHAPTER V + +BIRTHPLACE AND EARLY BEGINNINGS OF MAN + +INFLUENCES OF FOREST AND PLAIN ON BRAIN DEVELOPMENT + + +The place of man’s origin is a matter of little significance if he came +into being by a creative miracle. Any one of a hundred natal sites, +chosen for reasons of local pride or racial prestige, might have served +the purpose. Eden undoubtedly was most colourful, but otherwise it had +no exceptional advantages. Once created and upon his feet, man had the +world before him to conquer and possess. Such was the beginning and end +of his story. + +If, on the other hand, the human race came through evolution from lower +forms of animals, then man’s homeland is of utmost significance. It +must have exercised a strong influence not only upon his origin but +also upon all his life and progressive development. + + +_Africa, Europe, or Asia_ + +Some students of this subject have regarded Africa as the most likely +birthplace of man. According to this view the human form first appeared +as certain Nilotic negroes. From this homeland man spread throughout +the world. On the other hand, the accumulating fossil evidence of man’s +existence seems to be strongly in favour of western Europe as a centre +of human dispersal. Professor Osborn points out that between the years +1823 and 1925 there were discovered in this part of the world alone no +less than 116 individuals belonging to the Old Stone Age or to the Dawn +Stone Age. Two of these were members of the Piltdown race. Fossils of +forty other individuals belong to the Neanderthal race. Seventy-four +are accredited to the Cromagnon and other races that lived in late +Stone Age times. Remains of 236 individuals belonging to races that +lived between the end of the Old Stone Age and the beginning of the New +Stone Age were also found. These fossil men, in all 352 individuals, +have been discovered within the last hundred years. During the same +period, a little more than a century, only one human fossil has been +found in the entire continent of Asia, one in the Holy Land, and two +in Africa. Such a great preponderance in numbers clearly favours +Europe as the home of primitive man. Africa, Asia, and those parts of +Oceania formerly connected with the Asiatic continent, have borne no +such abundant evidence of man’s early presence. Both the northern and +southern continents of the New World have revealed nothing as yet that +may be accepted as representing man in his early prehistoric period. +This survey of the globe seems to limit the first appearance of man to +European regions. In this connection it should be borne in mind that +the various countries of Europe have been carefully explored in the +search for early human fossils, while in other parts of the world the +search is little more than just begun. + +Northern Asia has also been regarded as likely to contain the site of +man’s birthplace. This has been the view of certain French authorities +who consider the Eskimos as the most ancient northerly race of mankind. +From this homeland there was a progressive southward migration of +primitive tribes under the influence of the severe conditions imposed +by northern glaciation. More recently attention is being directed to +central Asia as the birthplace of man. This locality was suggested long +ago by the great American scientist, Joseph Leidy, and this viewpoint +has been supported by Professor Osborn. Dr. Matthews in considering +the matter of climate and evolution discussed the origin and migratory +history of man. He believes that Asia was the centre of dispersal +for human migrations, which were among the last of great migratory +movements of animals in the history of the world. It is his opinion +that most scientists to-day would place this centre in or about the +Great Plateau of central Asia. In this region, now barren and very +sparsely inhabited, are probably the remains of civilizations more +ancient than any yet recorded. Immediately around this region and lying +upon its borders are the territories of the earliest civilizations +known to man. Chaldea, Asia Minor, and Egypt lie to the west, India to +the south, China to the east. From this central region came successive +migrations, which overflowed into Europe during prehistoric, classical, +and mediæval times. The history of India shows that similar invasions +poured down upon it from the north. Toward the east, invasions in +successive waves entered the Chinese Empire and North America by way +of Alaska, spreading southward over the two continents of the New World. + + +_The Top of the World_ + +Since his recent visit to Mongolia, Professor Osborn is strengthened in +his conviction that central Asia will prove the homeland not only of +man but of all the greater forms of mammal life. Here, he believes, in +the Gobi Desert, were the ideal surroundings for the early development +of Dawn men who were the direct ancestors of the human race. His +belief in this part of the world as the birthplace of man depends +upon certain characters in the terrain which are essential to racial +development, concerning which he reasons as follows: Man’s earliest +existence was mainly in the open either along river bottoms and river +drifts or on uplands and plateaus. Such a life developed the finest +physical qualities of the race. The earliest man could not have been a +forest-living animal. Such parts of the human race as lived in forested +lands have either been exceedingly slow in their development or have +gone backward. Thus, the South American Indians, living in the forests, +are much behind those who live in the open. Of the latter, those who +live in the uplands are further advanced than those who lived in the +river drifts. An alert, progressive race cannot develop in a forest, +and it would be impossible for such country to serve as the centre of +human radiation. Higher types of men do not develop in a lowland river +bottom country, because food is plentiful and vegetation luxurious. It +is upon the plateaus and the high uplands that life is most exacting +and calls for exertions which are most beneficial for development. +Mongolia was probably a region forested only in part, certainly not +a country of dense forests. It was a most favourable upland country +throughout the entire Age of Mammals. Here the conditions of life +were apparently ideal, and since all other indications point to Asia +as the place of man’s origin, Professor Osborn looks to Mongolia and +Tibet, which he calls the top of the world, as the most favourable +centre offered by nature for the birthplace of man. Here he has hopes +of finding our remote human ancestors. He is, however, guarded in this +view, which he feels must be treated merely as an opinion. It is not +yet a theory, but is, however, an opinion sufficiently sound to warrant +further extensive investigation. In consequence, several great Asiatic +expeditions have been sent out by the American Museum of Natural +History into the Gobi Desert. Under the leadership of Dr. Roy Chapman +Andrews this exploration was undertaken in the search for fossil men. +One of the explorers, Dr. Nels C. Nelson, soon made the remarkable +discovery that in the wide expanse of this ancient desert there had +lived, ages ago, certain people whom he called “dune dwellers of the +Gobi.” His discovery included a great collection of flint implements +of the Mousterian type, closely resembling those found in the cavern +of Le Moustier in France, and thus belonging to the Old Stone Age. +These newly discovered implements reveal the existence of man at a +much earlier period in the Gobi Desert than the Mousterian period in +Europe. Indications of an earlier Stone industry were also found in +Mongolia. Some of these ancient implements show that long ago there +were probably men living in this part of the world who belonged to the +Dawn Stone Age. + +The latest evidence in favour of Asia as the home of primitive man +was supplied by a surprising fossil discovery made by Turville-Petre +(August, 1925). This new find consists of a skull of Neanderthal type, +discovered in Palestine and known as the “Galilee skull.” The rapidly +accumulating discoveries of the past three years sustain Professor +Osborn’s view that central Asia is the homeland of the human race. +He concludes that “while the anthropoid apes were luxuriating in the +forest and lowlands of Asia and Europe, the Dawn men were rising in the +invigorating atmosphere of the relatively dry plateaus of central Asia.” + + +_Home Surroundings Necessary to Human Evolution_ + +If, as a result of evolution, man took origin from lower animals, +these must of necessity have been mammals nearly like himself. They +must have borne and nursed their young as he did. Mammals other than +the primates differ so much from man that they could scarcely stand +in the direct line of his origin. How different from him are all of +the great races of hoofed animals, including the great varieties of +cattle, horses, deer, camels, giraffes, and elephants. All of these +are highly specialized and seem at once to exclude themselves even +as remote relatives of man. So it is also with the pawed animals, the +great families of dogs, cats, rats, and hares. These are definitely +quadrupeds, clearly designed to meet the issues of life upon four +legs. They fail to disclose anything resembling a near approach to +man, either in form of body or mental capacity. The winged animals +like the bats, strange specializations of the mammal kind, bear little +resemblance to the human form and offer a poor beginning from which +such a form might start. The swimming mammals, like seals, whales, and +porpoises, also exclude themselves from direct connection with the line +of man’s ancestry. In fact, all mammals must be put to one side in +considering this question, except a single remarkable group. The apes +and their kind alone bear an undeniable semblance to men both in body +and in behaviour. Many of their parts are similar to the human, such +as their hands and feet, fingers and toes all equipped with nails, as +well as their thumbs which may be held against each finger in turn. +The apes have acquired a more or less erect posture. Some of them, +called manlike apes (anthropoids), possess so many characteristics +in common with man that they alone of all animals might be regarded +as connected with the direct line of origin. If this relationship be +true, then the nature and location of man’s original homeland is of +profound significance. Wherever this place may be, it should bring into +combination two distinctly different types of home surroundings. It +should provide this combination in order that the apes might supply the +last long step by means of which man has ascended into humanity. These +two different but essential types of abode are: + +1. Home surroundings favourable for ape life. + +2. Home surroundings favourable to human life. + +A third condition must bring these two elements into final combination. +These specialized surroundings must be relatively near together, so +that transition from one to the other may readily take place. Does +Mongolia and particularly the Gobi Desert fulfil all of these three +conditions? + +According to Professor Osborn’s theory, the uplands and plateaus are +the most favourable places for human development. Such being the case, +we must also agree, then, that the forests are equally essential to +the life of apes. Only a few of these animals have adjusted themselves +to life outside of wooded country. Living in the trees, therefore, +is the existence that favours the life of the subhuman primates +(lemurs, monkeys, and apes). The forest provides the home surroundings +favourable for ape life, just as the plains afford those conditions +favourable to human life. Does such proximity of these two essentials +exist in the region of the Gobi Desert? Mongolia is not a densely +wooded country. It is a territory forested only in parts. In this light +it does not seem to be an ideal locality for the final transition from +ape to man. To explain this defect, Professor Osborn at present holds +that man in evolving had but a brief and very distant phase of tree +life. He believes that the quadrumanous arboreal stage was extremely +remote in geologic time. It was never a profound or exclusive mode +of life. There are those, on the other hand, who firmly maintain that +in this ape to man transition a long intermediate period of tree +living was necessary in order to bring about those changes in the +primate stock which laid the foundations for human existence. This +life in the trees was essential to determine the erect posture of man, +to free his hands ultimately for purposes other than locomotion; in +fact, to free them so that they might become the chief incentives in +the further development of the human brain. Even from this viewpoint, +Mongolia may still be considered the homeland of mankind. The forested +lands throughout its extent and upon its borders might well serve as +adequate surroundings for the development of life during that critical +intermediate phase when the first ancestors of men had parted company +with the apes and had at length become humans. + +With many animals there has been a strong tendency to take refuge in +the trees. The chief object of this tendency was to make life more +secure either by escaping danger or by obtaining food. But with the +coming of the ape kind this arboreal habit took a somewhat new turn. It +furnished the early members of the monkey kind a permanent abode. Such +a change to a more or less fixed dwelling in the trees produced marked +modifications in the animals themselves. It created a new type of home +and developed a new kind of thoroughfare over highways in the tree +tops. In order to acquire a proper equipment for such transportation, +both fore and hind paws became grasping organs. In consequence these +animals developed four hands. They gradually gave up the older pattern +of paw and claw, and by developing a new instrument connected with +the arms and legs they acquired a supreme facility for grasping the +branches of the trees. The tail also, in some cases, acquired similar +grasping powers. Thus, as the trees became the home and the highways of +these animals, their four grasping hands and their grasping tails gave +them a mastery over the forest which they used to their own peculiar +advantages. + +The forest background of their lives played an important rôle in the +molding of their behaviour. The perpetual semidarkness of their home +surroundings exerted a subtle influence upon them. It might be that +the forest in which they lived stood on the edge of a wide plain with +a clear opening from which to look into the farther distances outside. +Undoubtedly there must have been an alluring temptation in the green +plains and their inviting freedom. Yet for these tree-living animals to +venture into this open space was a hazardous undertaking. There were +many dangers lurking in the plain and over it. Fierce creatures of +every kind were there. Reptiles, mammals, and birds, all of them beasts +of prey, were lying in wait for just such an adventuresome excursion. +So for the time at least, and until they were better prepared to cope +with the enemies outside, the semidarkness was safer, even though the +view were limited and many interesting things were left unexplored. + + +_Effects of Tree Life_ + +The lemurs were probably the first of these new tree-living animals. +Their bodies were still slender and furry, their heads long and +fox-like, their eyes widely separated, and their tails long and bushy. +But in their hands and in their feet they showed the real beginning of +fingers and toes. This stage marks the transition from some lower form +of mammal to the primates (lemurs, monkeys, apes, and man). It was a +profound change, and in it the new order of primates had its origin. +The steps preceding this important one we shall consider subsequently. +But with this advance there began a period of tree living which +influenced all of these animals as they and their successors passed +through their many stages upward. The little animal known as Tarsius, +perhaps even more than the lemurs, shows the effects of these new +influences caused by tree-living habits. The monkeys of South America +reveal the manner in which the next step forward was taken. The effects +of it appear in the shape of the head, in the almost human expression +of the face, in the closer relation of the eyes to each other, and +in the shape of the nose and the position of the mouth. All of these +features prophesy the coming of the still more manlike apes. Above +everything else, these South American monkeys are conspicuous in the +history of development because of their almost human hands, and also +because of their hand-like feet. Most of the members of this group +acquired prehensile or grasping tails. With the appearance of the Old +World monkeys, this tail began to wane in importance. It lost all of +its grasping power and was reduced to much the same condition as in +other animals not of the monkey tribe. Some of the Old World apes, such +as the gibbons, developed the ability to stand and walk upright. In +addition to this erect posture these apes had passed through another +phase that brought them nearer to man. They had lost their tails. +This had come about, doubtless, from their habit of sitting upright. +The erect posture of the gibbons, however, was most important as a +forerunner of further developments in the great manlike apes, the +orang-outang, the chimpanzee, and the gorilla. These animals had grown +so large that for most of them living in the trees was a matter of +some inconvenience. It was necessary for them to come to the ground +at times, because they found it difficult to swing from tree to tree +like the smaller monkeys. Of the great manlike apes, the orang-outang +still adheres rather closely to the forest. The chimpanzee, which +has developed even greater cleverness in climbing, seeks the ground +oftener. He has learned to walk upon all fours, using the knuckles +of his hands as a support in this act. Like the orang-outang, he can +stand up quite erect and walk like a man. Finally the gorilla, the +largest of the manlike apes, often attains the size of nearly four +hundred pounds in adult life, and standing erect may reach the height +of nearly six feet. He also is able to walk upright. But the influences +of tree living are so strong even with the gorilla that he has not +yet made a good adjustment for life upon the ground. If it were not +for the prodigious strength in his great arms it would be difficult +for him to take to the trees, and he thus shows a betwixt and between +specialization, not entirely suitable for the ground and too large for +security among the trees. + +All of the manlike apes are capable of standing and walking in the +upright posture, but in this posture they are awkward and inefficient. +Their awkwardness is due to the fact that the foot in all three of +them retains many characters of a hand. None of them has a good foot +for effective heel and toe walking on the ground. Yet in spite of the +handicaps in their poor feet, in spite also of their long, ungainly +arms, these apes are able to venture beyond the limits of their forest +home. Some of them live in the plains or on the mountain sides. By +their great strength they are equipped to cope with many of the dreaded +enemies outside of the forest. The orang-outang seems to have no +natural enemies because of its own great offensive power. Only two of +the larger reptiles presume even to attack it--the crocodile and the +python. According to the natives of Borneo, the orang always succeeds +in killing the crocodile through main strength by standing upon its +back and opening its jaws until he is able to tear out its throat. +It is reported that if attacked by the python, the orang seizes the +reptile with both hands, squeezing it with such force and biting it +so ferociously that the outcome of the combat is soon decided in +favour of the anthropoid. The gorilla also has conquered most of its +antagonists in the animal world, and is regarded as the most powerful +and the most dangerous brute enemy of man. All of these apes have +acquired a certain freedom in using their hands, which are thus made +available for acts of self-defense and even for a considerable degree +of exploring their surroundings. + +Progress in the direction of mankind had its beginning when the +tree-living tendency of the apes began to recede. The recession of +such tree life paved the way for those first indecisive but promising +steps which took the great apes out of their ancient forest homes into +the inviting plain. Finally with the complete passing of tree life +there began that long and adventurous journey which was to lead over +every sea and into every land, until no region of the earth remained +for further conquest, until the full development of the hand and the +upright posture had more and more bent the forces of nature to the +designs of the races of man. + + +_Stages in Developing the Erect Posture_ + +The advances made toward mankind through the intermediate stepping +stones of the great apes and smaller monkey kind may be traced through +successive stages of tree life up to the time when the fully erect +posture became an accomplished fact. These stages have been recognized +as a result of exhaustive studies made by Professors Gregory and +Morton. They consist of gradual changes which finally gave rise to the +human foot. This structure permitted man at length to stand upright and +thus gave him the free use of his hands for constructive purposes. + +The first stage came in the Eocene (beginning of the Age of Mammals, +about 65,000,000 years ago). At this time certain four-footed +land-living animals began to live in the trees. This arboreal life had +profound effects upon the fore and hind paws. In order to climb among +the branches a clinging grip was necessary. Long, sharp claws developed +in consequence of this requirement. The digits of the paw were short +and the palms well padded. The thumb also was short but not opposable. +As yet there was no squatting or half-sitting posture. The toes were +likewise short and clawed. The heel was lifted off the ground. The sole +was well padded and the great toe large. These four-footed animals +made only an imperfect adjustment to tree life. Their movements were +slow and their range of action correspondingly limited. The tree shrew +is a good living example of such animals, while certain fossils of +the Eocene belonging to this type have been described by Professors +Matthews and Gregory. + +The second stage in developing transportation came with certain light, +lemur-like animals. They were still slow and cautious in getting +about and depended upon a clutch-like grip. This new kind of grasping +produced long digits like fingers. The toes were changed in the same +manner, so that the feet began to look more like hands. (Living +examples of this stage, _Loris_ and _Lemur potto_.) + +The third stage was a more decisive advance since transportation +through the trees now combined the advantages of climbing and leaping. +Locomotion was swifter and more effective. A tendency to a partially +erect posture developed, and squatting or sitting up was tentatively +established. All of the fingers became much longer. Most of them had +finger nails, so that these animals at last possessed what might be +called a hand. Changes of the same type took place in the toes. The +thumb and the great toe became more powerful and both were opposable. +They could be brought in contact with each of the other fingers or +toes in turn. In these animals the hands were now well formed and the +feet looked much like hands. It is for these reasons that such animals +are called quadrumanous (four-handed). (Representative animals of this +stage, _Lepidolemur_ and _Notharctus_.) + +The fourth stage was but a short step from leaping and climbing to +swinging from branch to branch or running along the branches. This +swinging by the hands is called brachiation. It had far-reaching +influences upon all subsequent stages. Such swinging naturally +lengthened and strengthened the arms. It produced a better grasping +grip around the branches and caused the fingers to grow longer. The +thumb did not participate in this increase of size. It actually was +reduced in strength and prominence. This is true in most of the New +World monkeys. In some of these, like the spider monkey, the thumb +has disappeared altogether. It should be remembered that most of +these animals had a prehensile tail which they used much like a +fifth hand. The foot also developed a grasping grip and looked if +anything even more like a hand than before. All of the South American +monkeys, besides their ability to swing from the limbs of trees, can +run along on the top of the branches in what is known as “pronograde” +locomotion. But their swinging propensity probably had the greatest +influence upon the final developments of transportation. It tended to +bring the body in a close approach to the upright position. Many of +the Old World monkeys sat in a semi-erect sitting posture, and from +their habit of squatting developed thick pads (ischial callosities) +over their buttocks. The leg became lengthened but was yet too much +flexed at the hip to permit of the most complete erect posture. This +stage is represented both by the New World and Old World monkeys, with +the exception of the baboons. These latter animals are an interesting +variation. They more or less deserted the old custom of living in the +trees. Their bodies and heads assumed many dog-like characters, and +they returned to a four-footed ground-living type of locomotion. In +consequence their limbs became shortened, as was also true of their +fingers and toes. All of these important changes took place in the +early part of the Oligocene (second period in the Age of Mammals, +probably 30,000,000 years ago). + +The fifth stage occurred much later in this period when another +decisive advance was introduced. For one thing, the tail entirely +disappeared. The legs became more extended at the hip. Swinging from +branch to branch was the chief means of getting about. This produced +extremely long arms and hands, and because this swinging mode of +transportation was predominant it kept the trunk more and more in the +upright position. Such straightening up of the body introduced the most +positive influence toward standing erect up to this time. The legs +did not grow in proportion to the arms, and the feet retained a close +resemblance to hands. On the ground such animals as these could make +their way with considerable speed, standing upright and running much as +man runs. The only difference between this kind of gait and that of the +human was due to the great length of the arms and the poor feet. + +This stage in the development of the upright posture is often seen in +motion pictures of those animals which portray this particular phase +of locomotive advance. These are the remarkable apes known as gibbons. +Those familiar with them in the zoölogical gardens, or in moving +pictures, will remember the peculiar way in which they run upright, +holding their long arms stretched out much like balancing poles. Thus +erect, they speed about in getting their food or playing with other +monkeys. Their upright gait is awkward but extremely interesting. +Once, however, they get into the trees their locomotion has all the +grace of a bird in flight. This gibbon stage of development was one +of extreme importance, since it gave the primates preceding man their +first chance to stand upon two feet and to run about in something +like human fashion. It is this stage that many authorities consider +indispensable in the final working out of the human erect posture +and human locomotion. Many students of this question also believe +that the upright posture could never have been attained unless animal +life had passed through that particular phase in the development of +transportation called brachiation. It seems certain that this stage +itself was dependent upon a preceding and extremely long period of life +in the trees. + +The sixth stage developed early in the Miocene (third period of the +Age of Mammals, about 15,000,000 years ago). One of its chief factors +was a great increase in the body weight of the apes. This greater +weight caused the animals to come nearer to the ground, as is the +case of the chimpanzee and the gorilla. These animals actually spend +much time upon the ground. In consequence, it was necessary for them +to make certain transportation adjustments. Their locomotion in the +trees was still of the brachiating type--that is, they depended largely +upon their arms for swinging. The arms thus became long and powerful. +When the gorilla stands erect his hands hang below his knees. The legs +are relatively short, but the feet in consequence of living so much +on the ground look less like hands than in the lower apes. They have +well-recognized broad heels, but flat soles without much of an arch. +The lesser toes are human in appearance. They are much shortened and +have little resemblance to the fingers of a hand. The great toe is +shorter and only in a slight degree opposable. This is especially so in +the mountain gorilla, in which the great toe bears a striking likeness +to the same part in man. The flexion of the leg at the hip is somewhat +decreased and as a result the gorilla is able to stand upright in +almost human fashion. All of these changes appear, to a less degree, +in the chimpanzee also. Both gorilla and chimpanzee are able to stand +erect, to walk, and even run in this posture. Their gait, however, is +awkward. They are greatly hampered in their locomotion by the extreme +length of their arms. Usually in getting about on the ground they run +upon all fours, using their arms somewhat like crutches and coming +down at each step on the knuckles of the flexed hand. When aroused +or charging to the attack, the adult male gorilla usually stands +upright and beats its fists upon its chest, at the same time emitting +a terrifying growl. When it is necessary for the animal to make speed +in flight or for other purpose, it usually comes down upon all fours. +Arboreal locomotion in all of the three great apes still retains much +of the brachiating type. It thus requires the retention of the hands as +part of the locomotor apparatus. Tree life in the chimpanzee and the +gorilla, combined with partial use of the ground, did much to develop +the essentials of the erect posture. It did not, however, free the +hands to that extent which permitted their exclusive use for purposes +more constructive than transportation. However strong the inclination +toward life upon the ground may have been in the manlike apes, they +were committed long ago by their predecessors to a life in the trees. +This commitment still kept them true to their kind and to their simian +inheritance. If they were to be more than apes, it was necessary for +them to shed the stigma that tree life stamped upon them. This the +modern apes were never able to accomplish. + + +_The Parting of the Ways_ + +At length, however, in spite of many obstacles, the tendency toward +the erect posture found a new opening. It was the foot that led the +way to this great opportunity. It provided an efficient supporting +structure with a well-developed heel, a non-opposable great toe, and a +sole containing an effective longitudinal arch. Man could at last stand +upright and be secure upon a capable pair of feet. At some period late +in the Miocene two branches from the stock of those animals, which had +managed to get into something approaching the upright posture, parted +company. This was a critical juncture. Thenceforth one branch proceeded +one way and the other followed an entirely different course. The apes +accepted the trees as their lot. Man, because of his two human feet and +what they supported above them, acquired the earth and all it contains. +Thus with tree life a thing of the past, with a true ground-gripping +foot, with longer legs, with an actual erect posture, the hands were +finally liberated for the purposes of human success. + +The development of the human foot, which must have been in progress +through vast periods of time, marks the decisive parting of the ways +between the apes and the races of men. It is doubtless true that the +specialization of the hand has been a potent influence affecting the +expansion of the brain and of brain power. The hand itself, however, +was ultimately dependent for its free and unhampered use upon the +development of the foot. This great factor was the forerunner of all +those elements in structural organization which finally brought about +the erect posture, which set the head upon the shoulders so that the +eyes might look forward and upward, and at length made it possible for +the eyes to guide the actions of the hands. + +Step by step, the brain has kept pace with these progressive +alterations. Old and new parts of it alike bear the imprint of +adaptive change. The combinations determined by life in the trees and +by the development of four hands have been worked out through graded +stages, from the humblest of the monkey kind up to man. Beginning +with the lowly tarsius and lemurs, this advance may be traced through +intermediate phases to its ultimate goal in the human brain. Mongolia, +as many authorities agree, may have been the land that saw man’s +earliest beginnings. Whatever his homeland, a long period of tree life +was necessary to develop in his predecessors those specializations by +which he rose to his allotted position. It is in the tree-life part +of man’s history that we see the dawn of the primate brain; for it +was then there occurred the earliest exploits of that great order of +mammals, the primates, to which all the monkeys, the great apes, and +man belong. + + + + +CHAPTER VI + +DAWN OF THE PRIMATE BRAIN + +THE LOWEST OF THE MONKEY KIND + + +We are now approaching a critical period in the history of the brain. +It is a period that contains many incidents of the utmost importance. +Particularly noteworthy are the episodes which favoured the production +of human characteristics in the animal kingdom. These characteristics +showed many manlike tendencies that much later were to appear full +fledged in the human race. They were from the first limited to a +single, highly interesting order of mammals. And this seems especially +strange because from the beginning of the Age of Mammals (65,000,000 +years ago) a great variety of new animals came into existence. The +fact that a single group out of all this vast number was picked out +to develop human resemblances must hold the secret of some potent +selective influence. Such an influence was definitely at work. Its +operations were slow but steady. Little by little it changed and +reshaped the structure of the body until at length there appeared a +race of animals so human in their organization that they might well +have been the forerunners of mankind. + +It would be difficult to conceive the kind of modification in structure +that could produce the form of man from a horse, from a whale, or +even from a dog. But this difficulty becomes far less in the case of +the animals usually referred to as the monkey kind. In many features +of their structure these animals resemble men. Existing in a great +variety of forms, they manifest numerous modifications in the different +parts of their bodies and exhibit a wide range of behaviour in their +habits. Only a superficial acquaintance with them is necessary to +reveal their many progressive traits. But their progress, like all +other progress, had its humble beginnings. At first the apes were +very simple creatures. Their coming, however, marked the dawn of a +new day in animal life. We shall be interested to follow the advances +that occurred in their mental capacities as they slowly made their +progressive strides forward. We shall be particularly struck by those +changes which gradually led up to the development of a brain capable to +control all of the complex activities of human behaviour. + +Naturally we may expect to find a simple controlling organ in the +lowest of the monkey kind. As we pass upward, however, into the higher +families of the apes, we shall not only observe a pronounced increase +in manlike tendencies but, as the great anthropoids at length become +human in miniature and then almost human, we shall recognize in these +animals a brain which very closely resembles that of man. + + +_Class Distinctions in the Monkey World_ + +In the ape world there are animals of high and low degree. Some are +so humble that it is hard to decide whether they actually belong to +the monkeys or not. With few exceptions they all prefer to live in the +jungles and tropical forests. We could not fail to be impressed by +the striking resemblance that many of them bear to man. Yet there are +such marked differences among them that they cannot all be regarded as +members of the same family. If we grouped them as we do human races, +we might most advantageously assign them to certain large classes +according to their nearness to man. + +Monkeys of lowest degree include the lemurs, the tarsiers, and all of +the New World monkeys. + +The intermediate monkeys in the next higher grade are those which live +in the Old World, with the exception of the three great manlike apes. + +The higher anthropoids occupy the top rank and are the nearest to man +both in their appearance and in their habits. + +These three ranks in apedom did not appear at the same time. One rank, +so to speak, successively developed from another. By a process of +selection and adjustment the higher forms arose from the lower. The +ranking great apes owe their superiority to many traits and characters +which they inherited from more humble forerunners and which they +improved by the process of progressive development. The lowest monkeys +likewise had their day of upward progress, during which they emerged +from some mammal still lower in the animal scale. These forerunners of +the earliest primates, the lemurs and tarsiers, had in all probability +been gradually specializing during the latter part of the Age of +Reptiles. Their ancestors came from that stock of mammal-like reptiles +which started from lowly beginnings and remained modestly in the +background during the reptilian period. + + +_The Lemurs_ + +In the endeavour to get some conception of these distant predecessors +of the monkeys and apes, it is believed that the tree shrews possess +those simple characters necessary for the proper starting point. +The shrew is an insect-eater and lives in the trees. It has many +specializations in its legs, in its head, and in its trunk. These +special adjustments might serve as the beginning of those important +changes in the body which later distinguished the monkey kind. In +the first place, the small size of the tree shrew was particularly +favourable for this purpose. Then, in the second place, its habit of +living in the trees foreshadowed advantages of great promise. Such an +epoch-making adjustment made its appearance when paws were replaced by +hands and when definite hand-like feet appeared. If an animal like the +tree shrew were the forerunner of the monkeys, it is not difficult to +appreciate how the lemurs arose from this stock. They and their kind +may be looked upon as the first chapter in the history of the ape world +and the ape brain. At present they live exclusively in Madagascar and +its small adjacent islands. They are not known in any other part of +the world, although fossils of them indicate that they were widespread +throughout the globe in earlier times. The reasons for their present +exclusiveness and their insular homes are not clear. Geologists claim +that the parts in which they live originally had land connection with +the continent thus permitting their wide dissemination. The later +disappearance of this connection accounts for their present isolation. + +There is much in the appearance of the lemurs that distinguishes them +from the monkeys and apes. Their most distinctive feature, the head, +is much like that of a fox and is drawn out in a long pointed muzzle. +Many characters appear in lemurs not seen in monkeys. They have no +cheek pouches. Their tails, never prehensile, are usually furry. They +develop no gluteal pads, which many apes possess in consequence of +their squatting postures. It is in their hands that they resemble +monkeys most strikingly. They have fingers and toes with finger nails +and toe nails. The thumb and great toe are always well developed, but +the second or third digit is often greatly modified. They also have +mammary glands like the monkeys. In the female these glands assume +certain definitely human characters. The lemur is a little smaller than +the domestic cat. Its fur is thick and woolly. Its large and prominent +eyes are more widely separated than in monkeys. The ears are long and +have tufts of hair on their upper portions. The arms are not quite so +long as the legs. The tail is long and often bushy. Fleshy pads appear +on the palms of the hands and soles of the feet, as well as upon the +palmar surface of the fingers. These enable the animal to grasp the +branch of a tree with great tenacity. + +Little is known of the lemur’s habits in the wild state. It is not +strictly nocturnal, for some of these animals are known to seek their +food during the day. Often they travel about in troupes consisting of +many individuals. Most of them live in the forest. Their food consists +of fruits, insects, birds’ eggs, and birds themselves, which latter +they are most skillful in catching. During the heat of the day they +sleep with the head beneath the arm and the tail curled about the neck. +When walking they go upon the hands and feet, both when on the ground +and in the trees. The tail is used in the manner of a balancing or +steering organ. Sometimes they assume a semi-erect posture on the hind +legs, or sit in a half-crouching position. Both hands and feet are +employed primarily for climbing or running about on the ground. + +The lemur has great ability in leaping from tree to tree. Its movements +are so rapid that it can only with difficulty be followed by the +eye. Hunters say that it is easier to kill a bird on the wing than a +lemur when leaping. If pursued and shot at it has a habit of dropping +suddenly from the topmost branches into the bushes, giving the hunter +the impression that he has succeeded in killing the animal. This +impression is soon dissipated upon seeing the lemur in another tree +at a considerable distance from the spot where it fell. When wild the +animals are said to subsist largely upon bananas. They also seem to be +fond of the brains of birds. After fracturing the bird’s skull with +their teeth, as they might puncture a nutshell, they suck the brain out +of the brain case. The lemur, however, does not eat the rest of the +bird. We may see from this description that this is an animal of great +agility. Not only does it possess much speed in its locomotion, but it +also manifests the utmost nicety in balancing and remarkable precision +in all movements. + + +_Tarsius_ + +Another of these lowest monkeys is a strange little animal called +tarsius, which has acquired a notable reputation. Several learned +authorities have singled it out as the standard bearer of human origin +from some lower mammal. The tarsius is about as large as a small +squirrel. Its appearance is peculiar because of its closely set bulging +eyes, its long tufted tail, its protruding ears, and the small circular +pads on the end of each finger and toe. Tarsiers have two curious +habits that attract attention at once. They can leap with astonishing +swiftness from tree to tree, often in pursuit of insects, and when they +turn their heads they seem at one instant to be looking forward and the +next directly backward. Their eyes, though very large and prominent, +do not seem to give them the best of eyesight. The animals can see +well at night, but during the day they appear to be almost stupid +because in the sunlight their vision is imperfect. Tarsius lives in +the jungle, usually in the low countries of the Malay Islands. During +the day it passes most of its time clinging in a vertical position to +the trunks of the smaller trees and underbrush. The way in which it +supports itself is interesting and peculiar. With its fingers and toes +it firmly grasps its slender support, at the same time pressing inward +with its long tail, which acts like a spring against the tree. If its +tail is pulled away from this support the tarsier at once tends to slip +backward. The tail, which has no grasping power, is used like a rudder +for balancing and steering when the animal is in motion. + +In some respects tarsiers are quite human. They go about in pairs and +are not gregarious like most of the monkeys. Furthermore, they give +birth to but a single offspring at a time. After the breeding season +the female and her young find a home by themselves. There are no +indications that these animals build nests or even live in holes of +trees. The tarsier often falls asleep in its characteristic clinging +position, and the head then sinks downward much as that of an old +man asleep in his chair. Often the young tarsius will perch upon the +mother’s head while she is asleep, and in this position fall asleep +itself. The general behaviour of the animal is extremely stereotyped +and limited. It learns but little under training. In captivity it is +able to make but few new adjustments. During the day its enormous +bulging eyes give it an almost ridiculous appearance as it gropes +awkwardly for food. This no doubt is due to the fact that its eyes are +constructed for hunting at night and do not contain the specialization +essential to the sharpest kind of vision. On the ground tarsius leaps +like a frog but is very awkward. In the trees, however, it is extremely +agile, and is probably the quickest jumper of all mammals. While +grasping a small branch it can turn its head so as to look directly +backward and jump more quickly than the human eye can follow. It seems +to be looking in one direction and jumping in another. This is due +to the great rapidity with which it turns its head. In captivity it +is pugnacious and cannot be tamed. It performs its toilet much as a +cat does and thus keeps itself scrupulously clean. It is not known +to make vocal sounds indicating fear or anger. On rare occasions, +and particularly when young, it has been heard to squeak. The infant +tarsius clings to the hair of the mother’s chest like other young +monkeys. The eyes are open at birth, and many reactions appear at once +that are long delayed in such animals as the rat, cat, dog, and higher +apes. + + +_The Marmosets_ + +Another lowly monkey is the marmoset. It has less renown than tarsius +but is nevertheless an interesting animal. It is often carried +around in the pocket of its owner and fits conveniently inside of +the old-fashioned fur muff. The marmosets belong to the group of the +New World monkeys. They inhabit South America and Central America. +Their chief interest arises from the fact that they represent one of +those moments of faltering experienced by the monkeys in their upward +strivings. These little animals have an almost pathetic expression +and features that are in many ways quite human. Yet in spite of this +human-like appearance they indicate an actual backsliding in the +attempts at progress. This backsliding is most apparent in their +fingers and toes. In fact, the entire hand and foot have lost most of +their human resemblance. The finger nails are now replaced by sharp, +talon-like claws, and the toes are equipped in the same way. The +marmosets, both because of their diminutive size and the imperfections +in their hands and feet, are now looked upon as monkeys that show signs +of retrogression. + +The marmoset is as large as a small squirrel and covered with a thick, +silky fur. It is naturally very timid but soon becomes friendly to +those with whom it is familiar in captivity. The female produces +two or three young at a birth and in this respect is unlike most of +the monkeys. The marmoset’s facial appearance and shape of head are +certainly more ape-like than the lemur’s. The eyes are set much closer +together, and are separated by a flat, narrow nose suggesting that +vision now depends on the simultaneous operation of both eyes. The +animal has a long, bushy tail. It lives in the tree tops or small +underbrush and climbs the trees in a manner similar to the squirrel. +Although it has a cat-like agility, it does not make the long and +daring leaps characteristic both of lemur and tarsius. It often loses +its grip on the branches and falls from a considerable height to +the ground. In captivity it shows little inclination to develop new +actions. It is not easily trained, and to teach it to do tricks of any +kind is most difficult. It lives upon worms, insects, and fruit. It is +known also to invade birds’ nests and suck the eggs. Very rarely does +it prey upon bird life and then only when it is able to overpower one +of the smaller birds or unprotected young. + + +_South American Howling Monkeys_ + +In this group of lower monkeys we encounter one with a highly +interesting personality, known as the “red howling monkey of South +America.” He is a real monkey, noisy and disagreeable, often attaining +the size of a fox-terrier. He always seems to be in an unpleasant +mood, showing his teeth and howling on the slightest provocation. In +spite of all this ill temper, he belongs to the progressive party +of the monkeys. There is not the slightest doubt that he has made +definite advances along the lines of progress. If we should question +this progress we would soon have our doubts set at rest when we saw +the astonishing manner in which he uses his tail like a fifth hand. +Even more convincing in this respect is the almost human appearance of +his hands. Not long ago a young woman visiting the ape house in the +zoölogical gardens was struck by these human similarities. She was +still more impressed when a large howling monkey thrust his long tail +through the bars and deftly tossed her hat into the air. + +The howling monkeys enjoy this gift of a capable, grasping tail in +common with most of their fellows who live in South America. The +prehensile tail is especially well developed in the spider monkeys +and in the woolly monkeys. At its end this tail looks like a long, +tapering finger. It is a highly developed sense organ and gives the +monkey a new instrument for locomotion and for exploring. These monkeys +are able to swing themselves from the branches by their tails and thus +leave the hands and feet free for other purposes. + +In addition to this highly efficient tail, the howlers have developed +a larynx and vocal cords with which they produce awe-inspiring sounds. +Their mournful howlings are often audible for miles around, and it +is supposed that they employ their cries as a means of defense to +intimidate their enemies. The howling monkeys possess a slightly +opposable thumb and well-developed fingers. While they are described as +being the most ferocious of the South American monkeys, they are also +credited with a low degree of intelligence. The face of this monkey is +naked with the exception of a heavy beard that hangs beneath the chin. +In captivity they are practically untamable and soon die. Their fur is +usually black, but in some cases is brown or reddish brown. They live +largely upon fruit, although like other South American monkeys they +feed upon caterpillars and insects. + + +_Measuring the Mentality of New World Monkeys_ + +Professor Thorndike, of Columbia University, has made careful studies +concerning the behaviour of several South American monkeys. He was +chiefly interested in the manner in which monkeys differ from other +animals in the mental capacities and methods of learning. In making his +tests he devised certain experiments which utilized boxes with pegs, +bolts, bars, and hooks. The object of these tests was to find out how +the animal learned to release itself from confinement, or gain access +to a goal containing food. Professor Thorndike concluded that these +monkeys did not learn by reasoning. They do, however, form more and a +greater variety of associations than other mammals. Their combinations +of this kind are remarkably slow and ineffectual in providing any new +behavioural accomplishment. Concerning the general mental development +of the South American monkeys, Dr. Thorndike believes that they +represent a certain advance from the generalized type of mammals +toward man. This is particularly true of their sense equipment and +their localized vision. All of this, he believes, is in reality an +advance due to the brain acting with increased delicacy and bringing +into line those activities which distinguish human mental faculty from +that of all other animals. Here, at length, among the lower monkeys is +well-attested proof of some progress toward the development of human +capacity. + + +_Monkey Behaviour_ + +The way in which these lower members of the monkey kind behave deserves +particular attention. It gives us the opportunity to observe certain +striking resemblances to our own human behaviour. This question +is one of primary importance. It acquires especial interest as we +compare the brains of the monkeys and apes one with another. As the +brain continues to improve from one stage to the next, we should be +on the lookout for new developments in behaviour. It might perhaps +be impossible to appreciate all of these minute changes among the +monkey kind. It is even somewhat questionable whether such an exact +comparison at the present time is necessary or possible. Yet there +are certain outstanding traits of conduct that may be easily traced +from stage to stage. One of the most important of these traits depends +upon the development of the tail from the time when it first acted as +a rudder-like organ for steering and balancing the animal until it +acquired all of its great facilities as a fifth hand. After this it +began to recede in importance and finally disappeared. The tail thus +created a special cycle of behaviour which had important bearing upon +the final outcome of man’s adjustment. + +Another group of reactions centre upon the manner in which the hand +made its appearance, including the progressive changes in behaviour +when the monkeys first became four-handed. All of these changes +were dependent upon living in the trees and gradually found their +culmination in an animal that could stand upon two feet and use its +hands. Such usage as this foretold the beginning of human skill, of +human right-handedness, and of human speech. + +Very important were the changes in behaviour that made their appearance +as the eyes worked more in harmony with each other. They produced a +kind of vision better able to guide the movements of the hand and +give more complete information concerning distance, direction, +and perspective. But far exceeding all other changes for getting a +better control over the surroundings were those progressive advances +introduced for making the fullest combinations of sense impressions. +These advances favoured the development of better powers for learning +and for profiting from experience. Progress in all of these particulars +concerning the behaviour of the monkeys may be clearly traced in +corresponding expansions in their brains. + + +_Brains of the Lower Monkeys_ + +In the brains of these four very simple members of the monkey kind +we may readily see the expansions that promoted development in the +governing organ. It will be apparent at a glance that progress followed +no direct or easy path. It met many rebuffs and obstacles. Often it +faltered and even stumbled. But struggling on it finally reached solid +ground and then went forward to real advances. + +Placing the brains of the lemur, tarsius, marmoset, and howling monkey +side by side we may see how this progress began. To guide our way in +following this advance, certain signposts and milestones will prove +serviceable. Three of these landmarks are deep grooves or clefts. They +appear in the superbrain and indicate the places in which progress has +been particularly active. Around these grooves the outer covering of +the superbrain has been folded to make room for more brain cells. This +folding produces convolutions with the result that the more convoluted +a brain is, the more cells it has for the development of brain power. +Each of these three grooves has its own special meaning as a landmark: + +1. The “Sylvian groove” is a fissure that runs between the department +for the sense of hearing, called the “temporal lobe,” and the +department for body and contact sense, called the “parietal lobe.” + +2. The “central groove” is a fissure between the department for body +and contact senses and the department of supreme brain activity, called +the “frontal lobe.” This lobe of the brain is situated immediately +above the eyes and behind the bone of the forehead (frontal bone). A +small frontal lobe means a low brow with a correspondingly inferior +mentality. As this lobe of the brain increases from ape to man, the +forehead gradually becomes higher and more prominent. + +3. The “ape groove” separates the occipital lobe in the back of the +head from the parietal lobe. In the occipital lobe is situated the +department for sight. + +The three grooves form the boundary lines between the four chief +departments of the superbrain, each of which is known as a lobe; +namely, (1) the parietal lobe, department of body and contact senses; +(2) the temporal lobe, department of hearing; (3) the occipital lobe, +department of sight; and (4) the frontal lobe, department of the high +mental faculties like judgment and reason. + +Further advances from this point will occupy our attention in tracing +the brain of the monkey kind upward. Two other landmarks in the +brain have special value. One of them is the bridge (pons) which +connects the larger brain (cerebral hemispheres) with the lesser +brain (cerebellum). This lesser brain acts as the chief muscle timer +and adjuster. It balances one muscle’s action to that of another and +adjusts the force of such action. All of our most exact movements, +whether in walking or writing or speaking, depend upon the little +brain. If it is injured or destroyed the movements of our hands and +feet, head and trunk, become shaky, unsteady, and very irregular. For +an animal to become highly skillful requires high development in the +little brain. The animal having the highest intelligence also possesses +the greatest capacity for skill in its actions. The size of the bridge +reflecting the degree of this skill is a good index of the intelligence +possessed by the animal. + +The pyramid is another important indicator of progress. Like the +bridge, it is found on the base of the brain. It is called pyramid +because of its somewhat pyramidal shape. It acts as the main trunk +line for getting the orders of the superbrain out to the muscles. +It transmits, so to speak, the highest commands of the brain in +controlling the motor machinery. By means of it we act according to the +dictates of our wills. If both of these great pyramidal trunk lines +are interrupted, we become completely paralyzed. The pyramids conduct +the highest output of the brain’s activity and increase in direct +proportion as the animal’s behaviour becomes more and more complex. + +The brains of low monkeys are of small size: lemur, 18 grams; tarsius, +6 grams; marmoset, 6.2 grams; and howling monkey, 24.5 grams. + +Size and weight of brain, we must bear in mind, vary to a considerable +degree with the size of the body, so that certain other signs of +expansion in the brain are more impressive. These signs clearly +indicate that progress is under way as follows: First, the large +superbrain begins to cover over the lesser brain. In lemur this +extension backward has only just begun. It is only slightly more +marked than in many of the lower animals, like the cat and the dog. +In tarsius the large brain has extended backward over the lesser +brain to a considerably greater degree. This is an important change +because the tarsier has transferred much of its business of sight to a +new department in the occipital lobe of the superbrain. The marmoset +shows this transfer carried a little farther, for the large brain now +overhangs the lesser brain. The great advance shown in the howling +monkey reveals the way in which the superbrain has taken complete +control of the situation. It now covers over the lesser brain entirely. +All of this change in the superbrain has been mainly in the interest of +making a better department for sight, but the departments for the sense +of hearing and for body and contact senses have not been behindhand in +expanding in these lower monkeys. + +Another pronounced sign of progress is the gradual change in the +position of the groove of Sylvius. In lemur it is almost vertical, +as in the cat, in the dog, and other lower mammals. The arrangement +of other smaller grooves around it is also similar to that in lower +animals. In the tarsius this groove is equally primitive. It is +beginning to tip backward a little in marmoset. Finally, in the howling +monkey this groove has become quite oblique, as it is in most of the +apes and man. + +All of this change has occurred as a direct result of perfecting the +organization in the department of hearing. The more tilted the Sylvian +groove becomes, the better developed is the temporal lobe which carries +on the business of hearing. The tilting backward of this groove also +results from an increase in that part of the superbrain which lies +immediately about the groove. This is the parietal lobe, the department +of contact and body sense. It is in this department that the especially +important information concerning the movements in the hands and feet +is registered. Thus the tilting backward of the Sylvian groove plainly +tells the story of improvements in the departments of hearing and of +body and contact sense. + +Still another sign of progress appears in the central groove, which +has an equally interesting history. In the lemur this groove is just +discernible as a faint dent. In position it resembles a corresponding +groove in animals like the cat and dog. Lemur in this respect suggests +that in its striving to part company with the lower animals, to break +away from ancient contacts, and to get on an independent new line of +its own, it has not been entirely successful. This central groove +shows where the chief department of the superbrain begins, that is, +the frontal lobe. In the lemur this department is poorly developed. +In tarsius it is impossible to find anything that looks like a central +groove. This animal’s brain is an example of some of that hesitation +which was encountered in the path of progress. The same faltering +is also seen in the brain of marmoset, which has no central groove +whatsoever. These little South American animals, it must be remembered, +are thought to be backsliders, and this particular defect in their +brain strongly supports that conclusion. + +In the brain of the howling monkey we find the central groove now +well developed. The superbrain shows that it is at length pursuing +some definite policy of expansion in its most responsible department. +Emphasis in growth is now obviously given to the frontal lobe for +advancing the capacity to transact all higher mental faculties. In the +howling monkey this department may not have attained any high degree of +development, but its presence is undoubted, and from this relatively +simple beginning it is only a matter of further expansion to bring +into existence the most productive mechanism of the brain. The howling +monkey shows its superiority over all lower monkeys in another respect. +It has developed the ape groove, and by it the boundary between the +department of sight and the department for body and contact sense is +fully established. + +Viewed as a whole, the brains of these four lower monkeys show distinct +progress in the interests of developing a more efficient superbrain. +Each of the sense departments has gradually become better defined in +its boundaries, and doubtless correspondingly better organized for +the administration of its duties. Rising supreme above them all there +finally appeared the controlling department of the chief executive +in the frontal lobe. We see this in its earliest stage in lemur. It +assumes still more importance in the howling monkey. The departments of +sight (occipital lobe), of hearing (temporal lobe), of body and contact +sense (parietal lobe), show the effects of steady improvement from +lemur up to the howling monkey. If there have been some hesitations, +even some slipping back in the organization of efficiency, it is +because some of these animals were rather uncertain disciples of +progress. They may have been, as is probably true of tarsius, too +close to the starting point where the real advances of the monkey kind +began; or perhaps, like the marmosets, they ran into early difficulties +along the upward climb. It seems probable that they were not able to +extricate themselves with credit from these hazards or to overcome +the obstacles that confronted them. For this reason their brain shows +some actual backwardness. With these exceptions, however, the evidence +of progress is undisputed. It seems sufficient to convince the most +sceptical. The purpose of the progress is also sufficiently plain. It +clearly appears to be that effort toward promoting organization in +the superbrain so that the offices of the supreme executive might be +established in the permanent quarters of the frontal lobe. + + +_Measurable Improvements_ + +Any doubts due to lack of measurable proofs may be easily overcome +by several comparative measurements of the bridge and the pyramid. +The size of these structures, both of which reveal the behavioural +capacities of animals, has been carefully estimated. Accordingly the +bridge has been assigned the following values: lemur, .055; tarsius, +.057; marmoset, .095; howling monkey, .103. Thus the bridge, called +by some authorities an index of intelligence, shows distinctly the +advances made among these simple monkeys. + +Quite as striking are the figures for the pyramid, which indicate the +degree of voluntary control that the superbrain has over all actions: +lemur, .110; tarsius, .032; marmoset, .064; howling monkey, .137. + +From these figures the howling monkey stands in advance of his monkey +associates in the index of his voluntary control. Doubtless much of +this advantage is due to the high degree of hand-like specialization +in this animal’s hands and feet. But the grasping tail of the howling +monkey should not be overlooked. If tarsius and the marmoset appear to +stand lower than the lemur, it is because one of them is a primitive +type of animal with a much restricted repertoire of reactions, and the +other, the marmoset, is a backslider less richly endowed in the more +effective motor capacities. + +All of these features in the brain seem to coincide with progress +in the behaviour of the lower monkeys. They show the path which +progressive advance has pursued. In the beginning, emerging from those +strivings of lower mammals and with much of the mammalian heritage +handed down by them, the lemurs took the first step of the monkey kind +toward a new type of brain. There was prophecy in these early attempts +made by the lemur. In some degree at least they foretold what this new +kind of brain was to be. Obviously they had as their distant mark the +ultimate upbuilding of the superbrain until an adequate department for +the supreme executive of life was produced. If tarsius hesitated in +reaching out toward this objective, it was none the less travelling in +the right direction. The destination of this course was clearly visible +in the brain of the howling monkey and other similar monkeys of the +New World. In this manner the first primate steps toward a more highly +efficient type of brain were taken. The conditions of tree life both +incited and successfully urged them onward. + + + + +CHAPTER VII + +ON THE WAY UPWARD + +BRAINS OF THE OLD WORLD MONKEYS + + +We have seen that the first steps leading to improvements in the +primate brain were taken by certain humble creatures living in distant +parts of the earth, and by the great tribes of the New World monkeys +inhabiting South America and Central America. These steps did not lead +far along the path of progress. They were only a beginning, the first +harbingers of man’s arrival. Many lowly animals in the ape house at the +zoölogical gardens reveal numerous features suggestive of the human +being. Such features not only include their fingers, finger nails, toes +and toe nails, but even more their facial appearance. Many of these +monkeys look like diminutive old men. They snarl and show their teeth +when angry. Their way of indicating displeasure is almost human. They +make certain expressive gestures, like nodding or tilting of the head +to one side in a quizzical or even pathetic manner. They make plaintive +cries or sounds, in some cases almost like the notes of a bird, or they +scream out loudly in anger. All of these New World monkeys are notable +for one other reason. They do not make any of those humorous grimaces +that are so amusing in the Old World monkeys. These latter manifest a +certain drollness in their constantly changing facial expression. + +The Old World monkeys include about three quarters of all living +species. They are embraced in one great family, but the members of this +family show many differences ranging from the huge dog-faced baboon to +the small bonnet monkey. Some of them are gentle and affectionate, some +are savage, pugnacious, and treacherous. This entire family is spread +out over the hot or semitropical regions of the world. Many of its +members live in the damp, tropical forests; others prefer rocky, almost +barren country, and a few seek their homes in temperate climates. Some +monkeys are found among the lower ranges of the Himalayas and may be +seen in the winters playing among the branches of snow-laden trees. Two +varieties seem to have a surprising endurance in really severe cold. +They inhabit the elevated regions of eastern Tibet. + +In picturing to ourselves the characteristics of a monkey we are apt +to have the conception of an animal that can hold on and hang by its +tail. None of the Old World monkeys has this kind of tail. The greatest +number of them live in the trees, and the tail, while generally short +and stumpy, in some cases is decorative and almost plume-like. Most of +the Old World tribes are especially interesting and amusing because of +a large elastic pouch in each cheek. This pouch the monkey greedily +crams with food in his haste to get his meal into safe-keeping. When +the cheek pouches are filled both cheeks are bulged out and give the +animal somewhat the appearance of a gourmand embarrassed by a mouthful +of delicacies. Later on, at his leisure, the monkey chews and swallows +the food. + + +_Baboons_ + +By far the largest of the Old World monkeys are the baboons. They may +be recognized at once by three characteristics. The head and face look +much more like those of a dog than is true of other monkeys. They have +long and dangerous fangs in the upper and lower jaws. They go about, +like most four-legged animals, upon hands and feet which have much the +appearance of paws. + +Further acquaintance with the baboon shows him to be a surly, +unmannerly, savage, and thoroughly undependable creature. All of his +tribes have fleshy pads over the buttocks, which in some cases are +large and brilliantly coloured. Some members of his clans, such as +the mandrill, have faces which look like gruesome masks or hideously +painted savages. The skin over the nose is a fiery red, while the +cheeks are swollen, ribbed, and of a vivid blue colour. A beard of +golden hue hangs beneath the chin in contrast to the dull olive drab +of the body. Protruding over the lips are savage canine teeth, long +and dagger-like. These baboons are about as large as a good-sized +dog. The colouring of the face adds considerably to the repulsive +unattractiveness of the animal. They run along on their hands and feet, +with their eyes directed downward, so that they are obliged to elevate +the large overhanging eyebrows in order to look upward and forward. +They go about with the palms of the hand and soles of the feet laid +flat upon the ground. The mother is often seen walking or scampering +around with a young baboon clinging to her back. Sometimes the mother +will sit up on top of a rock just like a human being. Her offspring +often perches on her neck after the fashion of a well-trained acrobat. + +All of these monkeys are gregarious. They travel about in large +numbers. Often as many as a hundred individuals collect in one herd. +Because of their aggressive disposition, they are dangerous enemies, +especially when irritated or disturbed. Their long, sharply pointed, +canine teeth are capable of inflicting severe wounds. Although they +have no actual speech, they utter certain sounds that seem to be +thoroughly understood by all members of the herd. There is quite a +variety in these sounds. Some of them resemble barks, grunts, or +even screams. Often they make low and subdued murmurs with various +inflections, the meaning of which all the baboons seem to understand +immediately. Sometimes the slightest murmur from one of the members of +the herd will act as a signal or warning. This is particularly true +when the baboons are out on an expedition of pillage or mischief. +On such occasions they always station a lookout or outpost at some +favourable point from which the signal may be given upon the approach +of danger. The faintest murmur made by one of these lookouts will start +the marauding baboons scampering away to safety. + + +_Disposition of Baboons_ + +For the most part they live in rocky places near ravines, crags, or +hilly promontories where grass and trees are scanty. Their favourite +abodes are usually places surrounded by wide plains. This kind of home +enables them to lie in wait for the right moment to perpetrate some +thieving expedition upon a garden or field and at the same time to have +every opportunity of escape. They are much given to mischief of this +kind. Consequently they are feared and despised by the inhabitants of +the country which they infest. If attacked, they often turn upon their +pursuers and inflict serious wounds upon their assailants. Some baboons +prefer to live in the dense forest and climb readily about even in the +tallest trees. Those that live in more open country are very agile +in clambering among the rocks and are able to reach lofty heights or +positions of safety. The baboon eats a little of everything, although +its chief diet consists of roots, fruits, reptiles, and insects. +To procure their food they are continually searching, turning over +stones beneath which the desired food may be concealed. When young the +baboon is often quite gentle and affectionate, but with most of them +this disposition changes when they grow up. In captivity baboons are +surly and unfriendly. Even those born and reared in captivity are more +difficult to approach and teach than other apes. They are vindictive +and treacherous. Their disagreeable dispositions accord well with +their unpleasant and often repulsive facial expressions. Their savage +reactions and lack of intelligence have earned for them the reputation +of being the lowest of the Old World monkeys. Baboons seldom assume +the erect position for standing or walking. They do, however, sit upon +their haunches in a somewhat crouched position, but not so freely as +many other Old World monkeys. They all live in Africa, with a slight +extension into Arabia. It is well that these animals never grew to the +size of the great apes, for had they done so they certainly would have +been among the most dreaded and frightful creatures ever known on earth. + +Dr. Ditmars, who has spent much time in observing monkeys, reports +many interesting studies and experiments concerning their behaviour. +Apparently the habit of throwing missiles when enraged is not uncommon +among baboons. Any angry monkey may in its rage grasp and hurl an +object such as a drinking pan, but there is usually no accuracy in +its aim or intention in its act other than an expression of irritated +feelings. None of the monkeys has ever been known to use a stick or a +club in attacking others or defending itself. Although the throwing +of missiles is almost unknown among monkeys, the baboon marks an +exception. As an instance, one day Dr. Ditmars found the visitors to +the ape house almost in a panic, due to the savage behaviour of a +big yellow baboon. A part of the cement had fallen out of the wall +of his cage and broken up into sharp pieces. These pieces the baboon +was hurling at the visitors through the bars in a most deliberately +offensive manner and with effective aim. The crowd in consequence had +retreated to various points of safety. Later a shovelful of coal was +placed in the cage of this same baboon. The pieces of coal he also used +as missiles, throwing them with calculating aim at the keeper and other +attendants. The baboon seems to have an excellent throwing arm, and +Dr. Ditmars credits him with good control and much speed. During this +experiment a baboon of a different species acted in precisely the same +way. In both of these animals their pitching capacity was demonstrated +without any previous practice or instruction, and from these +observations it would appear that baboons are natural-born pitchers. + + +_Macacus, the Indian Monkey_ + +Another one of the Old World monkeys, the macacus, shows a different +side of the picture. He is more friendly, more gentle, more full of +fun, and forever up to some sort of monkeyshines. Many of these monkeys +live in India. Mr. Kipling has described them in his famous “Road Song +of the Bandar-Log”: + + Jabber it quickly and all together! + Excellent! Wonderful! Once again! + Now we are talking just like men. + Let’s pretend we are ... never mind, + _Brother, thy tail hangs down behind!_ + +These monkeys have their homes throughout the Indo-Malayan regions. +They extend northward into China and Japan and eastward into Tibet. The +macaques have a stout body and a proportionately large head. There is +considerable variation in the tail, which ranges from a long, sweeping, +plume-like appendage with a tuft at the tip, as in the lion macaque, +to a thick, stubby tail much like that of a dog which has been docked. +The pigtail monkey has a curled appendage. One of the macaques of +Japan has a mere stump, while the Barbary ape has no tail at all. The +macaques are the typical monkeys about which most of the favourite +stories concerning the ape kind have had their origin. Their enormous +cheek pouches, their facial grimaces, and the motion of their lips +make them unusually fascinating to watch. They are extremely noisy, +jabbering most of the time. They seem to have an extensive vocabulary +of sounds, consisting of shrill calls, grunts, low mutterings, barks, +chattering noises, and almost ear-splitting yells, which they emit +in moments of rage. They are playful and quarrelsome, and these two +phases of their behaviour pass without sharp line one into the other. +They never become involved in serious combats because they seldom +remain at one thing long enough to be effectual fighters. In their +quarters at feeding time they usually make a real pandemonium in their +frenzied efforts to stuff their cheek pouches as full as they can. +They have absolutely no consideration or courtesy on these occasions. +Their table manners are not only rough but actually ruthless, and the +most delicious morsels go to the strongest. The weak, the young, and +the female obtain what is left or go without. These monkeys are often +docile and affectionate. They make the most amusing kind of pets. No +animal is more mischievous or more destructive about a home where there +is anything within reach to break. Sometimes when they grow up they +develop the unpleasant tendency of being too strictly a one-man animal. +To protect their owner against an imaginary danger they will often +attack strangers or visitors. + + +_Behaviour of Macacus_ + +The head of the macaque is much less dog-shaped than that of the +baboon. The eyes are set closely together, and the animal sits on its +haunches a good deal of the time holding its head upright, so that +the eyes are directed forward. Its posture in sitting is quite human, +while its attentive gaze gives the impression that it is watching +intelligently all that is going on. Its nose is short and has a fairly +good nasal bridge. The lips are thin and the upper one is particularly +long. The hands and feet closely resemble human hands, except that the +palm is not so broad, the fingers are longer, and the thumb shorter. +In its movements the macaque is remarkably deft. It changes from one +position to another with surprising swiftness. These monkeys go about +in herds, often of considerable size. If captured young the animal is +easily trained and quickly learns many amusing tricks. It is full of +mischief and curiosity. Macacus monkeys frequently become a nuisance +in the neighbourhood of towns where they live in large numbers. When +full grown they are sometimes quite ill tempered and often savage even +to the extent of attacking the inhabitants without much provocation. +For the most part they live in cultivated tracts along the banks of +streams. They seem to seek rather than avoid the habitations of +man. They manifest little fear for their human neighbours and take +a real delight in molesting them by many annoying pranks. Sometimes +their attentions are vigorously resented and their human neighbours +turn upon them. Their behaviour on such occasions is like that of +tantalizing small boys who take an almost idiotic delight in the +vain efforts of their pursuers to overtake them, and continue their +aggravating antics in order to prolong the excitement of the futile +pursuit. If one happens to be captured, a number of them will turn +back to take the part of the unfortunate captive. In their native +haunts they are constantly on the move. Repose is totally foreign to +their daily programme. Scampering, swinging, chattering, screaming, +they go among the trees all day long. Either their actions are without +design, or else their purpose changes so rapidly and frequently that +their behaviour has the appearance of ceaseless motion. When together +they are very quarrelsome, constantly nagging or teasing each other, +but here, as in all of their activities, the object of their anger, +the victim of their jest, is as quickly shifted as their fleeting +attention. Having no fear of the water, they are able to swim for long +distances and greatly enjoy it. They feed upon spiders and many other +insects, besides fruits and berries. As compared with the baboon, they +show a greater mental alertness. + + +_Mental Tests_ + +Considerable psychological study has been made of the macaques, +particularly concerning their ability to learn and their mentality. +Dr. Kinnaman, who has made some of these studies, believes that they +have attained a higher level of intelligence than that ascribed to +the New World monkeys by Professor Thorndike. He thinks there is some +evidence that the macaques have powers of reasoning, although of a low +order. Dr. Hobhouse agrees with this view and adds that the macacus +monkey seems to be possessed of definite ideas. Professor Yerkes, +after a longer and more systematic study with experimental methods +better suited to the problem, agrees with Professor Thorndike that the +macacus may have a certain number of limited ideas. It is clear to him +also that there are extreme differences in the mentality of different +species of monkeys. The slow process which they display in the solution +of problems is quite surprising, in many instances being actually less +rapid than in some of the lower mammals. + +One question is certain to arise at this point: How do the Old World +monkeys compare in mentality with lemur and tarsius and with the +monkeys of the New World? Perhaps the best answer to this question may +be obtained by watching the actions of these different animals in their +cages at the zoölogical gardens. Looking at a lemur as he jumps about +restlessly among the supports of his cage, it is quickly concluded that +this animal, not unlike a diminutive fox, is interesting only because +of his remarkable agility. Tarsius would probably not be found in +most zoölogical gardens because these animals do not survive long in +captivity. The marmosets would attract little more attention than the +lemurs, not only because of their small size, but also because of their +lack of interesting reactions. Howling monkeys, spider monkeys, and +woolly monkeys are more interesting because of the remarkable way in +which they use their tails like a fifth hand. Their facial expression +and their general behaviour, however, are somewhat monotonous. + +The Old World monkeys, especially the macaques, hold the attention and +create a real interest. Here is to be seen a busy world of jabbering, +mischievous, tricky, athletic monkeys whose antics easily rival the +best of human clowning. There can be no doubt that these Old World +monkeys are on a higher mental plane than those of the New World. +The main fault to be found with them is that they never get anything +really done, except perhaps filling the pouches in their cheeks just +as full as they can. Even the grouchy baboons show some signs of +better mental powers than the South American monkeys. They have a +thoroughgoing hostility for their human contemporaries which they have +never changed, and their powers of organized banditry show a degree of +mental capacity that is foreign to the lower monkeys. This capacity we +should consider all the more noteworthy because the baboon manifests +a distinct tendency to lose some of the benefits derived from living +in the trees. It almost seems as though, to a certain extent, it had +retrograded. This retrogression appears in the fact that many of the +baboon’s characteristics are less ape-like and more dog-like than +other Old World monkeys and also because its hands and feet seem to +be specialized more in the direction of paws. Yet, in spite of this +backsliding on the part of the baboon, the monkeys of the Old World are +as a whole eminently more efficient in their actions and capacities +than any of the New World monkeys, the lemurs or tarsiers. + + +_Brains of the Old World Monkeys_ + +A question may arise concerning the relation in point of time which the +Old World monkeys bear to those of the New World. All of the evidence +supplied by fossils indicates that lemurs and tarsiers, as well as +the monkeys of South America and Central America, came into existence +long before those species which inhabit Africa and Asia. According to +most reliable records, the monkeys had their start some time early in +the Age of Mammals. It is correct, therefore, to look upon the Old +World monkeys as a later and higher stage of development in apedom. +This conclusion is borne out when we view the brains of the macaque +and the baboon. In this comparison we may be able to detect many signs +indicating improvements in the brain; in fact, all doubts may be set at +rest concerning the superiority of Old World monkeys. + +If we look at the baboon’s brain we are impressed by the fact that it +has many more grooves and many more convolutions than the brain of the +South American monkey. The convolutions and the grooves of the brain +indicate the amount of cell space which the superbrain provides for +developing brain power. As between the baboon and the macaque, the +difference in this respect somewhat favours the former. This difference +is small and may perhaps be discounted by the fact that in macacus +the grooves have a slightly more advanced arrangement in consequence +of which certain departments of the superbrain show more progressive +tendencies than in the baboon. This is particularly true of the +department of hearing (temporal lobe) and the department of body and +contact senses (parietal lobe). Comparing the groove of Sylvius, whose +general angle furnishes such an important standard in rating a brain, +there is more of a backward tilting seen in this groove of the macaque +than in the baboon. Such an inclination is characteristic of higher +races. The central groove appears to be about on a par in both brains, +and the ape groove is likewise well developed both in the macaque and +the baboon. These three great boundary lines separate the four major +lobes of the superbrain. The department of sight in the occipital +lobe in macacus has no real advantage over the corresponding area in +the baboon. As already noted, the departments of hearing and of body +and contact sense are better organized and somewhat more expansive in +macacus than in baboon. But when we come to the preëminent part of +the superbrain, that portion in which the chief executive function is +located, namely, the frontal lobe, the baboon actually seems to have +some real advantage. Recalling the ugly disposition and ferocious +nature of this animal, we may question why he is superior in this +highest part of his brain to the lively and humorous little macaque. +It is unfortunate that we have not as yet any good psychological +studies of the baboon by which we may compare him with his more nimble +associates. Doubtless it is the disagreeable nature and uncompromising +aversion which the baboon has for mankind that make it so difficult to +estimate him psychologically. Yet there may be something of an enviable +consistency in the baboon’s aversion to man that implies a better type +of mental power than one might infer from the jabbering, ceaseless +activities of the macacus and all of the other bandar-logs. Some +explanation of this sort must at present suffice until we are possessed +of better standards for psychological comparison. + +The two important structures on the base of the brain furnish a +definite idea of an animal’s rating. Accepting their evidence, it +appears at once that the bridge (_pons_) bears out our previous +observations concerning the powers of the superbrain. This evidence +gives the baboon a higher standing in intelligence than the macacus. +The value assigned to the bridge in the baboon is .164, while in the +macacus it is .150. This contrast gives an interesting corroborative +estimate of the superior mental powers of the baboon. From the figures +indicating the relative size of the pyramid, it would seem that the +macacus is somewhat more richly supplied in his variety of skillful +movements than the baboon. The figure in macacus is .147 and baboon +.143. While this is not a marked difference, it seems to indicate an +advantage probably derived from the more nimble and acrobatic actions +of the macacus. This animal has acquired a more highly efficient +mastery of tree life as compared with the more sluggish tendencies of +baboons, most of which prefer to live upon the ground and go about +like other four-legged animals. These contrasts between the Old World +monkeys are interesting for what they show in themselves. They give +rise to many questions which we would be glad to see answered by more +exact and extensive study. The reasons why the baboon or the macacus +should be endowed with superior qualities in one particular or another, +or why there should be corresponding improvements in the brain, are not +clear. There can be no doubt, however, that in the Old World monkeys as +a whole both behaviour and brain are in many respects superior to the +monkeys of the New World. We cannot fail to discern the special points +of this superiority in the brain. It seems impossible to avoid the +conclusion that when the Old World monkeys made their appearance they +definitely advanced the cause of progressive improvement and that from +this progress the brain profited as much as or even more than any other +part. + +Turning back for a moment to the brains of the New World monkeys +and comparing them with those of the Old World group, we will find +sufficient evidence to convince us that the chief organ of the body was +surely on the way upward, and that the first humble steps taken by the +earliest members of monkey kind had been supplemented by further and +bold advances. + + + + +CHAPTER VIII + +MANLIKE TENDENCIES + +BRAINS OF GIBBON AND ORANG-OUTANG + + +There is little about the Old World monkeys, either in their mode +of life or in their appearance, to inspire respect or confidence. +The savage fierceness of the baboon, the mischievous nonsense of the +macaque, seem like flimsy foundations upon which to build a race +of intelligent human beings. When these animals first made their +appearance they were but vague foreshadowers of what mankind might +be. It is not alone their form and structure that interests us; their +actions, habits, and behaviour must be carefully studied at the same +time. + + +_The Anthropoid Gibbon_ + +Had the human eye been able to observe all that transpired in the early +days of the monkey kind, it would have been difficult to believe that +a race of men was in the making. It would have seemed incredible that +from these chattering, restless monkeys change and modification could +eventually bring forth that development necessary for the human form. +And yet in the course of time changes of this kind did bring into +existence an ape which bore a much closer resemblance to man. It was +then possible to foresee how, from this new kind of animal, certain +human features might be derived. This particular member of the ape +world is the gibbon. All of his tendencies make him somewhat shy and +inconspicuous. At the zoölogical gardens he is generally sitting high +up on a perch in his cage with his long arms folded over his head, +peering quietly about him. His fur is usually dark, although some +members of his family are quite light in colour. The most impressive +thing about the gibbon is the fact that he can stand up, walk, and run +upon two legs. This he does a little awkwardly, but not unlike a human +being. In a certain memorable moving picture, an unusually interesting +silvery gibbon nearly usurped the rôle of leading man. His marvellous +feats earned for him universal applause, and whenever he appeared he +was the centre of attention. Among its most stirring moments, this +picture shows a dramatic scene in which a great Indian elephant whose +young one has been captured demolishes the dwelling of the jungle +native who has trapped her offspring. Shortly after the native with his +wife and children has escaped to safety, the gibbon emerges cautiously +from the wreckage of the home. Through the darkness of the forest he +discerns the glistening eyes of a tiger that is about to spring upon +him. Realizing that retreat is cut off, he takes to flight. In escaping +he stands upright and runs like a man, screaming in his fright in a +thoroughly human manner. Fortunately for the gibbon, the branch of a +tree comes opportunely in his path, and then, with a single upward +bound, he is off like a bird through the trees to safety. + +Gibbons are gentle, affectionate creatures. They are also timid and at +the first sign of danger hurry away through the forest as far up in +the trees as they can go. The gibbon’s body and head are relatively +small, being only a little larger than some of the smaller macaques. +The animal’s legs are short and it has no tail. A prominent feature is +the exceptional length of the forearm and of the fingers. The hand is +slender and longer than the foot. The female bears one young at a time, +which the mother carries under her body, the young one clinging to the +fur on her chest with hands and feet. This burden does not embarrass +her in the slightest as she swings her way from tree to tree through +the forest. She makes as good time in this transportation as the +unincumbered males. + +In the wild state the gibbons never leave the jungle, and live for the +most part throughout southern Asia and the adjacent islands. A few of +them venture from the inland forests to the vicinity of the coast. +All of the gibbons are highly developed for life in the trees. This +specialization is important not only for the effects it has had upon +these apes but also for those developments in them which were to be of +subsequent and substantial advantage to the rise of man. + +There are many different varieties of gibbons such as the white-handed +gibbon, the silvery gibbon, the white-cheeked gibbon, the slender +gibbon. The animal that we shall consider is the hoolock gibbon of +India. He gets his name from a peculiar sound or cry which he makes. +If it were at all possible to imitate this cry it might be expressed +as “hooloo! hooloo! hooloo!” Mr. Candler has studied this interesting +animal at close quarters, and his account of its habits is well worth +quoting: + + The Hoolock swings along the thinnest part of a bough or to the + slender end of a bamboo, until it bends to its weight, then with + a swing and a sort of a kick-off he flies through the air seizing + another branch, and swinging along it with the accuracy of a + finished trapeze performer. I fancy he does very little walking in + the wild state, for I have never seen a wild Hoolock on the ground. + Moreover, they are only found in the dense jungle where the ground + is everywhere covered with tangled vegetation. The Hoolocks are + extremely shy and it is difficult to watch them as they are concealed + by leaves high up on the bamboo clumps or tops of forest trees. The + cry of the Hoolock is characteristic. It is a very pleasing note, + rising and falling in intensity, and reminding one somewhat of a + pack of beagles giving tongue on a scent, which is waxing and waning + in strength as a larger or smaller number of the band join in the + chorus. It is heard chiefly in the early morning, then through all + the heat of the day there is silence, but towards evening as the sun + sets you may hear it again. + +One might almost think that their early morning cry was like a rising +bell, and their cry toward evening was their curfew. + + +_Manners of the Gibbon_ + +Gibbons live in fairly large communities. They are constantly on the +move. From what is known of their intelligence it seems probable that +their movements are guided by definite plans. They even seem to have +some simple sort of governmental system. Tea planters in India often +keep these gibbons as pets for years. They run about the compound +quite freely. At times they suddenly disappear and are gone for several +months. Eventually they return quite unconcerned, as if nothing had +occurred to interrupt their pleasant human associations. For the most +part the gibbon is sociable. After he has become acquainted he will +often sit on the arm of a person’s chair at breakfast. Whatever his +appetite, he will never reach out for food at the table, although his +long arms give him much advantage over his human host. Nor will he +ever snatch things off the table. His manners are above reproach and +he keeps himself scrupulously clean. As the day is drawing to a close +it is his habit to get ready for the night. At sunset he settles down +to sleep, safely seated in the fork of a tree, usually with his long +arms over his head. He is never boisterous, mischievous, or noisy. +Oftentimes he seems to be more in sympathy with children than with +grown-ups. + +The diet of the gibbon includes a long list of foods, such as fruits, +leaves, and young shoots, spiders, birds’ eggs, insects, and young +birds. If captured young the gibbon is readily tamed. He is never sulky +or ill tempered and shows marked intelligence both in learning many +tricks and adjusting himself to the rules of the home. + +The locomotion of these animals among the trees is totally different +from that of the monkeys. The latter climb about using both hands and +feet. Gibbons employ their arms almost exclusively, swinging from +branch to branch, with the legs tucked close to the body. This is such +an important change in the transportation methods of apedom that we +should give it particular attention in order to note what effects it +had produced upon the gibbons themselves. In the first place, swinging +from one limb to another by the hands greatly elongated the forearm and +the fingers. This kind of locomotion gives the gibbon the appearance of +taking tremendously long strides with his arms. The right hand, first +grasping a branch, permits the animal to swing twelve or more feet to +the next branch which is grasped by the left hand. In the next step the +forward stride is taken by the right hand. Thus the animal alternates +the right and left hand just as we alternate the right and left foot. +It is probably for this reason that the gibbons have been called “tree +walkers” (_Hylobates_). + +The second effect produced by this kind of swinging locomotion, called +brachiation, is even more decisive in the final outcome. Transportation +such as this swinging by the hands drew the body more and more into the +upright position. It brought about many of those fundamental changes +which made it possible for the gibbon to stand upright, walk, and run +upon two legs. Compared with other animals of this class, the gibbon +is the most two-legged of all the apes. He walks rather quickly in +the erect posture. His gait is waddling, and if pursued he will make +every effort to reach some support by which he can swing himself to +safety. In walking he turns his leg and foot outward, which gives him +a bow-legged appearance, added to which the shortness of his legs +makes his movements in walking and running far less graceful than +these acts ultimately came to be in their highest exponent, man. Here +undoubtedly may be discerned important elements for the inception of +human locomotion. They appear in an animal which can stand, walk, and +run upright, and also possesses well-developed hands. + + +_Gibbon’s Resemblance to Man_ + +The gibbons are said sometimes to scoop up water in the hollow of the +hand in order to drink. At other times they stretch out their long arms +among the foliage and lick off the dew which adheres to their hair, in +this way quenching their thirst. + +In view of these facts our estimate of the gibbon may credit him +with certain manlike traits. Yet his resemblance to human beings, +considering the animal as a whole, is at best sketchy and vague. Casual +observation of the gibbon does not bring any clear association with +the human being at once to mind. Only after watching him, after noting +the manner in which he gets about, after seeing him walk and run on +two legs, is it possible to recognize certain tendencies which point +in the human direction. It is for this reason that the gibbon is said +to represent a stage preceding the manlike apes. Some students of +this question class the gibbon with these anthropoid apes. It seems +better judgment, however, to consider him rather an animal showing +dispositions which serve as a starting point for the anthropoids. +These tendencies, as they are crystallized in the gibbon, represent an +introductory chapter in the history of all those animals which later +became notable because they walked more or less upright and had the +use of hands. Thus the gibbon is often spoken of as pro-anthropoid. +He himself is a modern animal. One of his venerable ancestors, very +much like himself, lived long ago--_Propliopithecus_ of the Oligocene. +The descendants of this ancient extinct ape with the long name, +whose fossil remains have been found in Egypt, followed two lines of +development. One line led up to the modern anthropoid apes and man, the +second to the modern gibbons. The first offshoot from this line gave +rise to a great ape which in many features looks much more like man +than does the gibbon. This is the orang-outang. He is one of the big +apes seen in the large primate cages of the zoölogical gardens. He may +be recognized by the brownish-yellow hair which covers his body, by his +face which bears a humorous caricatured resemblance to man, and by the +erect posture which he assumes much of the time. Although he climbs +about his cage and its supports like a skillful acrobat, this manlike +ape lacks the grace and agility of the gibbon. He is wild and shy, but +possesses enormous strength, which makes him more than a match for the +most able-bodied man. + + +_The Orang-Outang_ + +The orang lives in Borneo and Sumatra. He has not been found elsewhere +in the world. In his island home he enjoys a deserved reputation +because of his prodigious strength. When full grown he stands a little +over four feet in height. He has a heavy body, short thick neck, +receding forehead, thick lips, and a face uncovered by hair. His muzzle +protrudes to form a thick and heavy upper jaw, with a large mouth and +large teeth. In the full-grown male the cheek pouches become greatly +enlarged, so that they look like an old-fashioned ruff around the head. +This feature gives him a hideous and gruesome appearance. The arms are +long, reaching almost to the ankles when the orang stands upright. +The hands are long and narrow, the thumb is short, the fingers are +united by webs at their bases. The legs are short in comparison to +the length of the body and considerably bowed. The feet are long and +narrow. The great toe is short, but it can be used for grasping the +branches. Fleshy pads over the buttocks are present in the adult male, +but the orang has no tail. He is easily distinguished from the other +great apes by his bulging muzzle and his light yellowish-brown hair. +He seldom exceeds four feet two inches when standing upright, but his +outstretched arms together measure nearly eight feet from finger tip +to finger tip. Some specimens killed by hunters have been reported to +stand five feet three inches high. + +Among the first accurate accounts of the orang-outang’s life is that +of Alfred Russell Wallace appearing in his famous book _The Malay +Archipelago_, from which the following description is an extract: + + The orang has a wide distribution, inhabiting many districts along + the coast of the island [Borneo] where it appears chiefly confined + to the low swampy forests. It particularly affects a country which + is low and level with a few isolated mountains, on some of which + the Dyaks have settled and planted many fruit trees which are a + great attraction to the orang, as his most desirable food seems to + be unripe fruit. The habitual habitat of the animal is in the lofty + virgin forests, in which they can roam in every direction with as + much facility as the Indian on the prairie, passing from treetop to + treetop without being obliged to descend to the earth. The orang + makes his way leisurely through the forest, with remarkable ease. + He walks deliberately along the larger branches, in a semi-erect + attitude which his great length of arm and the shortness of his legs + causes him naturally to assume. But this proportion between his limbs + is increased by his walking on his knuckles and not on the palm of + his hand. He chooses those branches which intermingle with those + of an adjoining tree. In approaching these he stretches out his + long arms, seizing the neighboring bough with both hands and then + deliberately swings himself across to the next branch, on which he + walks along as before. He never jumps or springs nor even appears to + hurry himself, yet he manages to get along almost as quickly as a + person can run through the forest beneath. The long powerful arms are + of greatest use to the animal, as they enable him to climb easily the + highest trees, to seize fruit and young leaves from slender boughs + which will not bear his weight and to gather leaves and branches from + which to form his nest at night. When wounded he endeavors to make + a nest in which to remain quiet, and similarly at night prepares a + resting place in the tree to sleep. He likes this place low down in + the tree, not over 20 or 30 feet from the ground, probably because in + this position it is warm and less exposed to the wind. + + The orang, it is said, makes a new nest for himself every night + or perhaps remakes an old one. In rainy weather the animal covers + himself with leaves or large ferns, and this may have led to the + belief that he actually builds huts in the trees. The animal does not + arise from his bed in the morning until the sun is well up and has + dried the dew upon the leaves. He seldom returns to the same tree two + days in succession. + + They have no particular fear of man, and only retreat slowly after + a considerable period of scrutinizing inspection. They do not have + so much of the gregarious tendencies as do the other large apes. Two + full-grown animals are seldom seen together, but males and females + are sometimes accompanied by half-grown young ones. At other times + three or four young animals are seen together. Their food consists + almost exclusively of fruits, leaves, buds and young shoots. They + seem to prefer the unripe fruit, even when very sour or intensely + bitter, the red fleshy arillus being a particular favorite. The orang + rarely descends to the ground except when pressed by hunger, when + it seeks the succulent shoots at the riverside. In very dry weather + it also comes down from the trees in quest of water, of which it + generally finds sufficient in the hollow of the leaves. They have + been seen upon the ground playing together, at which times they + assume the erect posture and grasp each other with their arms. + +Wallace believes that the orang seldom stands or walks erect unless +when using its hands to support itself by the branches overhead, or +when attacked. He also thinks that the representations of it walking +with a stick are quite imaginary. In its general demeanour the orang +would impress one as dull and apathetic. When seated among the branches +its back is bent, its head is bowed, and its long arms either reach +up to grasp a branch overhead or hang listlessly by its sides. Some +explorers have maintained that the animal builds huts for itself in the +trees. This is largely an exaggeration, but the orang has developed +an interesting technique for building itself a nest in the trees as +night approaches. Small branches are first laid crosswise to form a +framework, and over this a thick bed of leaves is placed. The orang is +quite fussy about the construction of its bedroom and takes good care +to cover itself up when the wind is chilly or the night stormy. Even in +captivity the animal is particular about the details of its bedchamber +and always manages to cover itself with straw or newspapers if it +happens to find them in the cage. + +The orang has other constructive tendencies. He often manifests some +engineering skill in devising supports for himself in his cage. With +these he will amuse himself by the hour, climbing upon the support, +dropping to the floor, and repeating the entire performance time after +time in as many different ways as he can. In one instance a young male +orang found a long rope hanging from the roof of his cage. He clung to +the rope by his left hand and both feet. With his free right hand he +passed the end of the rope around the bars, turned it through a right +angle, and pulled it tight. In this way he made an interesting perch +for himself. If anyone detached the rope he at once replaced it and +thus remade his perch. + +On the ground the orang is clumsy. He usually goes on all fours, and +his walking gait has been likened to that of a very old man bent down +by age, hobbling along with the aid of a cane. It is interesting to +note that in walking he goes on the outer borders of his feet. His +stride is short and shuffling. Even when hurrying he lopes along +rather than runs. Unlike the gibbons, the orang does not use his hand +as a drinking cup. His lower lip protrudes in a capacious trough for +collecting rain water. If given a pail of milk or water the orang lifts +the pail and pours the fluid into this trough and then swallows it. +When captured young the animals can be trained and taught to obey many +words of command. In time they get over their shyness and seem to like +human companionship. They are, however, easily frightened. Females when +pregnant separate themselves from the others and remain more or less in +seclusion until the young are born. The offspring grow slowly and, like +human infants, require the care of their mothers for a long time. When +the mother moves about the young one clings to the hair of her chest. +This is a marked characteristic of child care throughout the ape world. + + +_The Orang in Infancy_ + +Wallace recites an interesting experience which he had with a baby +orang whose mother was shot and killed by him in the forest the +preceding day. This experience is especially interesting because of +its many human resemblances. When Wallace stooped to pick up the +helpless infant orang that lay sprawling on its back, his long beard +was immediately seized by the grasping hands and feet of the youngster. +It was a long and painful ordeal to get away from this clinging infant. +The baby orang had but a single tooth, but soon its milk teeth began +to appear, much as in a human infant. The lack of milk on the island +made it difficult to feed the young ape. When a finger was placed in +its mouth it would suck with great vigour, drawing in its cheeks in +a vain effort to extract milk. After persevering for a long while it +would give up in disgust and start screaming, much as would a human +baby under similar circumstances. When handled or nursed it was always +quiet, but if laid down by itself it would invariably cry. It enjoyed +being rubbed after its morning bath and was quite happy while its hair +was being combed and brushed. + +For the first few days it clung desperately by all four hands to +everything it could reach, and Wallace remarks that it was necessary +for him to be cautious in keeping his beard out of the way. He felt +that the infant ape was lonely and needed companionship, so a little +harelipped monkey of the macacus variety was obtained as a playmate. It +was curious to see the difference in the actions of these two animals, +the one an offspring of a humbler monkey, the other born of one of +the great manlike apes. The two young ones were about the same age. +The orang, just like a human baby, would lie upon its back helplessly +rolling from side to side, stretching out all four hands into the air +and striving to grasp something, although hardly able to guide its +fingers to any desired object. When dissatisfied it opened wide its +almost toothless mouth and expressed its discomfort in an infantile +scream. The little macacus monkey, on the other hand, was constantly +on the go, running and jumping about, examining everything in sight, +taking hold of objects with greatest precision, balancing itself on the +edge of its box and searching everywhere for food. There could scarcely +be a greater contrast. One could hardly escape the conclusion that in +the orang, as in man, a long period of slow growth is necessary for +its final development. The advantages of such growth are sufficiently +apparent and need no further comment. + + +_Psychological Tests_ + +The orang-outang has not yet been so extensively subjected to +psychological study as its more sociable fellow ape, the chimpanzee. It +is fortunate, however, that at least one of this species has come under +the critical observation of an astute student of animal behaviour, +Professor Robert M. Yerkes, of Yale University. In his notable +contribution on the mental life of monkeys and apes, Professor Yerkes +has described certain tests devised for estimating the intelligence of +lower animals, and applied to the partly grown orang known as “Julius.” +These tests were devised on what is known as the “multiple choice +basis.” Julius, after many unsuccessful efforts to solve his problems +by the method of trial and error, quite unexpectedly seemed to get the +idea of what was wanted. He suddenly responded to the test without a +single mistake. He seemed to solve his problem quite as if he knew what +it was all about. It took him a long time, but at last he showed that +he was capable of some kind of thinking. The curve of learning as it +was charted day by day from the actions of Julius indicated that if he +had been a human subject his mental process would possibly have been +described as rational. Professor Yerkes feels justified in concluding +from this evidence that the orang solves his problems ideationally. +In general, Julius appeared to be far superior to other monkeys in +his intelligence. His mental processes were slow, but the method of +learning by ideas seemed to replace the simpler way of trial and +error which is common throughout the monkey world. Julius persistently +endeavoured, and often vainly, to gain some insight into a situation. +Even though slow, he showed nevertheless that the brain had at length +attained the development necessary for the production of real ideas. +However questionable this attainment may be in the monkeys or in other +lower animals, there seems to be little doubt about its existence in +the orang. + + +_Brains of the Gibbon and Orang_ + +Upon reviewing the facts concerning the gibbon and the orang, we may +ask certain questions. For example, does the real progress which these +two members of the ape world show in their capacity to do things +manifest itself as a measurable difference in their brains? Would it +be possible to maintain that these were indeed the brains of more +capable and more intelligent animals than the monkeys? Certain features +about the brain of the gibbon and the orang are striking. In the first +place, the pattern of their convolutions is more complicated. The +orang especially has more grooves and convolutions upon the surface +of the superbrain. It is believed, and many facts sustain the belief, +that convolutions indicate in a general way the capacity of an animal +to develop brain power. In the gibbon the increase in convolutions +is not so pronounced as in the orang, although it is not difficult +to see that in this respect the gibbon’s brain is much improved when +compared with lower monkeys. Upon identifying the familiar landmarks, +it is obvious that the groove of Sylvius, the central groove, and +even the ape groove form more decisive boundaries and outline more +prominent lobes than in macaque or baboon. The superbrain departments +for sight (occipital lobe), for hearing (temporal lobe), for body +and contact senses (parietal lobe), are all more extensive. Each +lobe, by the presence in it of smaller secondary grooves which do not +appear in the lower monkeys, shows how its capacity has expanded. The +grooves of the brain, in their arrangement, number, and relations, +now begin to assume an appearance similar to that of the human brain. +Each sense department in the orang is well organized. Each has gained +in prominence, thus indicating how the senses of sight and hearing, +and body and contact senses, have increased their capacity. By means +of its amplified sensory combinations the superbrain was eventually +capable of producing intelligent reactions. The area in front of the +central groove manifests the chief improvement. This is the part of +the brain in contact with the frontal bone. It has made some advances +in the gibbon but is still more prominent in the orang. At this stage +it is possible to speak of a well-developed frontal lobe acting as the +headquarters of all higher mental functions. The large increase in the +size of the orang’s brain is in some degree proportional to the size of +the animal’s body. Many other factors have actuated this expansion and +will receive special consideration in a subsequent chapter. + +If it were possible to reduce the difference in intelligence between +the orang and the gibbon to actual figures, the contrasts would be +marked. Certain estimations of this kind are significant. The bridge +(_pons Varolii_) on the base of the brain, which may be regarded as +an index of intelligence, has a value of .200 in the gibbon and .300 +in the orang. The pyramid, indicating the degree of skill in movement +attained by the animal, as well as the degree of controlling itself by +the dictates of its will, also shows a considerable difference. This +difference is again in favour of the orang, whose pyramid is estimated +at .160, while that of the gibbon is .138. + +Many other points indicating similar advantages held by the orang over +the gibbon might be cited. They have the same general meaning, namely, +that the orang possesses a better brain. In fact, all of the evidence +gathered from this animal reveals many manlike tendencies. Such +tendencies, both in brain and behaviour, first became notable in the +gibbon. At this stage they were not prominent features. They were, so +to speak, in a preparatory or pro-anthropoid phase. In the orang those +manlike tendencies foreshadowed by the gibbon became more definite and +better developed. They formed the foundations for new combinations out +of which was to emerge a still higher type of animal. + + + + +CHAPTER IX + +HUMAN IN MINIATURE + +THE BRAIN OF THE CHIMPANZEE + + +The chimpanzee has a well-established reputation for many sterling +qualities. He is a comedian of no mean talent, and often as a buoyant +fun maker earns a large salary. He is also famous as an acrobat. + +Depending upon his species, the chimpanzee varies in height from four +feet to four feet five inches. As a class these apes are spread out +over more territory than any of the other great anthropoids. They live +in West and Central Equatorial Africa ranging from Gambia in the north +as far south as Angola. In colour they are black with thick hair over +the entire body, except the brow and face. In some species the scalp +is bare, as in the bald-headed chimpanzee. All varieties are powerful +but lightly built animals. They possess great strength and agility. In +spite of his relatively short stature, the chimpanzee is a dangerous +enemy even for the strongest man. His head is flattened in the region +of the forehead, which has a thick bony ridge above the eyes. The ridge +of the nose is flat. The mouth is large and the lips thick. The ears +are especially large and project upward almost as high as the vertex of +the head. The lower jaw protrudes considerably. The teeth in general +are large and formidable, the canines in particular being prominent. +The skin over the face is usually dark, but in some species it is +lighter than surrounding areas. This is particularly true in the region +of the mouth and nose. The body is short and the abdomen pendulous. +The legs are shorter than the arms. The foot is short with a great toe +that is thick and opposable. The other toes are united by a web near +the base. The arms are long, with finger tips reaching a considerable +distance below the knees when the animal stands erect. The hands are +broad, the thumb is short, and the fingers webbed near their bases, as +in the case of the toes. As is true of the other great anthropoids, the +chimpanzee has no tail. The female bears one young at a time, which she +carries when passing through the forest and along the ground in the +manner characteristic of other apes. + + +_Intelligence of the Chimpanzee_ + +Concerning the habits of the chimpanzee in its native state little +is known. Fortunately, many of these animals have been captured when +young. Some of them have become noted circus performers, or famous +moving-picture actors. A number of them have been studied from the +standpoint of their behaviour and psychology. One of the best records +of the chimpanzee comes to us as an echo of the Great War. It furnishes +another instance of German thoroughness and scientific enterprise. + +Some years ago the Prussian Academy of Science established at Teneriffe +in the Canary Islands a special station equipped for the study of +the great manlike apes. It was here that Professor Köhler found +himself during the Great War and here he remained interned with nine +chimpanzees for two years. During this time he lived with these animals +largely shut off from the rest of the world by the naval blockade. +The report of his experience and studies is given in a delightful +narrative published both in English and German called _The Mentality +of Apes_. The following descriptions of the chimpanzee are taken from +Professor Köhler’s book. In this work his chief purpose was to test the +intelligence of the larger manlike apes. To this end it was necessary +to devise certain methods which he called “roundabout tests” because +they complicated ordinary situations in such a way as to require +intelligence on the part of the animal for their solution. + +Early in the study one of the most quick-witted chimpanzees in the +collection was given the following problem: From the roof of the +animals’ playground a basket of bananas was suspended by means of a +string passed through an iron ring. The end of this string was tied +in a noose and placed over the limb of an old tree at a height of +nine feet from the ground. When all was ready, the chimpanzee called +“Sultan” was sent out into the playground. He, of course, was familiar +with this basket and associated it with feeding time. On entering the +enclosure Sultan saw the basket at once and then began to manifest +signs of agitation because, contrary to custom, he was all alone in the +open. He began at once to show his feelings in true chimpanzee style. +Jumping about he expressed his extreme disapproval at being alone by +making a thundering noise with his feet against the wall of the ape +house. It seemed as if he were calling upon the other chimpanzees to +come out and join him. He even tried to get in communication with the +other animals by climbing up and looking in at their windows. But +all of this was to no avail. Presently he appeared to take a renewed +interest in the bananas. He looked up at the basket, and having sized +up the situation made for the tree, climbed quickly to the noose, +pulled the string until the basket bumped against the roof, released +the string, pulled it a second time even more vigorously, until a +banana fell to the ground. Sultan then left the tree, but soon ascended +once more, now to pull violently upon the string until it broke and the +entire basket fell. Immediately he scampered down, took the basket, and +went off in a corner to eat the fruit. Thus Sultan, in a comparatively +brief time, solved this roundabout problem by obtaining the objective +in spite of the obstacles put in his way. + + +_The Chimpanzee’s Use of Implements_ + +Many experiments were made to see how much the chimpanzees make use +of implements, but in the main these experiments were not necessary. +The chimpanzee, as if by nature, handles many objects in his immediate +surroundings in a variety of ways. His powerful hands serve in a +most natural manner as a useful link between him and the world of +things outside. His feet, although far more than a second pair of +hands, may be used in emergencies when the human feet would be quite +useless. The jaws and teeth are also serviceable, and are employed as +among many African tribes and other primitive people. The handling +of everyday objects by the chimpanzee comes almost entirely in the +nature of play. Sometimes under the pressure of need it appears that +new knowledge acquired from using objects at play will be put to still +better use in gaining some desired objective. In the main, however, +what the chimpanzee may use in this way is without the slightest idea +of immediate gain and serves only to increase the joy of living. +Thus jumping with the aid of a stick or pole, invented by one of the +brightest chimpanzees, was imitated by all the others as a means of +entertainment. Later it was put to more practical use for obtaining +food which was suspended above them and out of reach. In order to get +this food it was necessary to resort to some means of lifting their +body toward the desired goal. In the end the jumping with a stick in +play was converted to a sort of pole vaulting by means of which the +chimpanzees all acquired a thoroughly businesslike method for getting +such food as was out of reach over their heads. These chimps also used +straws and twigs as we use spoons. At first this was more or less in +play during mealtime, especially after their first thirst had been +quenched. Then they liked to amuse themselves by dipping the water up +with a straw and sucking the straw. Once some red wine was poured into +the drinking water which they shared in common. At the first taste of +this new mixture they all paused for a moment and looked at each other; +then one of the chimpanzees began to spoon up this wonderful drink +with a straw, and all the others immediately followed his example. In +learning to use twigs and straws for spoons there was no possibility of +imitation. None of the chimpanzees had a chance of seeing a human being +use a knife or spoon while eating. The twig or stick was also employed +quite deftly in other ways, adding to its usefulness as a table utensil +some of the properties of a weapon for the chase. In the summer time a +species of ant infests the part of the Canary Islands where these great +apes were housed. These ants passed in a wide stream, moving along +over the beams, around a wire netting which encircled the playground. +The chimpanzee has a great liking for acid fruit, which he prefers to +all others. It is no doubt for this reason that he relishes the formic +acid in the ants. Usually upon seeing the ants the chimpanzee simply +rolled his tongue along a beam over which they were crawling and thus +gathered them in to himself. If the wire netting came between him and +this coveted delicacy, such a method of capture would not suffice. In +consequence, all of the chimpanzees soon learned to use sticks and +straws, which they thrust through the wire netting and held in this +position until covered by ants. The straws were then withdrawn, and +the insects promptly licked off and devoured. This method of capture +proved most satisfactory and entertaining. Their attention was entirely +absorbed in the process of overcoming the obstacle between them and +the delicate morsels which they craved. + + +_Strong Human Resemblances_ + +If a mouse, a lizard, or some small crawling animal entered the +playground, the chimpanzees at once became greatly excited. They +manifested all of the hunting interest apparent in the human species +under like circumstances. There was also evidence of fear and timidity +on these occasions, not, however, confined to the female alone. Even +the bolder chimpanzees that evinced the greatest hunting interest did +not give chase with any creditable show of courage. They manifested +caution and hesitation throughout the entire performance. Nearly +every movement on the part of the poor quarry was followed by nervous +gestures of the chimps. The largest ones hesitated to make a capture +by a sudden snatch with the naked hand. It was amusing and almost +laughable to see these powerful apes stretch out their hands with the +evident intention of catching the prey, with fingers all pointed in +anticipation, then suddenly, on the slightest movement of the mouse +or lizard, quickly withdraw the hand again. A firm grasp upon one of +these little wriggling animals appeared almost as impossible for the +chimpanzees as for many people. Despite the great excitement which the +presence of invaders occasioned, the little animals would often escape +because the chimpanzees lacked that last degree of daring necessary to +make a successful capture. Presently they learned to use sticks upon +the small intruders of their domain. With these weapons, if the victim +did not escape, they would at length dispatch it. This they did in no +spirit of cruelty but rather in sheer excitement of the chase. + +Professor Köhler took great pains to observe the rapidity with which +the chimpanzees adjusted themselves when confronted by new conditions +for the first time in their lives. One of the most striking tests +of this kind was their introduction to the electric current. It was +decided to observe how the chimpanzees would act when they made the +acquaintance of this entirely new circumstance. For this purpose one +wire from an electric induction coil was attached to a metal basket +filled with bananas and suspended from the roof. The other wire from +the battery was made fast to a metal netting upon the ground beneath +the basket. In a short time all of the chimpanzees became intensely +interested in the fruit above their heads. They were particularly +eager to reach the bananas. To do so it was necessary for them to +stand upon the wire netting on the ground. At first one chimpanzee +approached cautiously. Having taken up his position with both feet +upon the wire netting, he reached slowly up to the metal basket. +This of course immediately made a connection which delivered an +electric current through his hand. The reaction of the chimpanzee was +astonishingly human. Immediately upon touching the basket he felt the +shock of the current and with a cry of dismay bounded off in great +surprise. His curiosity, however, was not yet satisfied. He still +had a hungry longing for the bananas. Everything about the situation +looked thoroughly familiar and innocent to him. He could see no reason +why the basket on this occasion should treat him so rudely or why he +experienced such an unpleasant sensation in trying to get his food as +he had done a hundred times before. Appetite and curiosity finally got +the upper hand, and stealing up cautiously he made a second attempt. +This time he was less hasty in grasping the basket and spent several +moments in hesitating attempts to touch it, drawing his hand back now +and again. At length, with a sudden grasp, he reached for the goal, +only to receive another shock. In apparent indignation he hopped away +in much the same manner as might any human being who had inadvertently +touched a hot stove. Nothing would do, however, but that all of the +chimpanzees in turn should follow the example of their leader and try +to get the bananas away from this strange thing that seemed to be +outwitting them. One after another they made their futile attempts +until it became a pathetic sight to see them sitting around in a +mournful ring, sometimes looking at their hands, sometimes shaking +them resentfully, and always gazing wistfully at the inaccessible +delicacies. Most of the chimpanzees during this test reacted in a +manner which might easily be called human. It was rather impressive to +observe that all of their reactions under these conditions were actual +counterparts of human behaviour. + + +_Chimpanzee Sports and Nest Making_ + +In handling other objects the chimpanzees showed a strong tendency to +develop new habits. After a time they did not confine themselves alone +to thrusting and hitting with sticks. They soon began to throw them +around. In moments when they were greatly pleased (and chimpanzees +have a joyful, buoyant nature) they showed their delight in a new way, +especially when very good food was being provided. On such occasions +one of them would seize another and shake him violently out of sheer +pleasure and approval. Under such provocation a large chimpanzee +developed the habit of taking a stick and flinging it forcefully +at some comrade in his vicinity. This frequently happened in play +also. One female, a remarkable athlete called “Chica,” developed the +amusing pastime of stealing up behind her companions as they sat +quietly at rest, and from fairly close quarters hurling a stick at +them. Immediately she would scurry off, apparently much delighted by +the discomfort that she had caused. From throwing sticks it was but a +short step to throwing handfuls of sand at one another, and finally +stones of varied size and weight. At first their aim was poor, but soon +throwing stones became a ruling passion among them, and some of them +became dangerously expert, especially the wily Chica. She practised so +continuously that she soon acquired great skill and an excellent aim. +From this pastime she appeared to derive much satisfaction, whether +hurling stones at her fellow apes or at her human associates. Both +ape and man acquired such a genuine respect for her ability in this +regard that whenever they found her in this mood they quickly retired +to safety and permitted the expert marksman to find her amusement on +less sensitive targets. All of these hurling activities, which were in +the nature of play, might for a few moments determine an exciting stone +battle. But the sharpshooting Chica was so obviously superior that the +fray was certain to be short lived. + +Almost all of the chimpanzees made nests for themselves, even from the +earliest infancy onward. In these operations, as might be expected, +the full-grown chimpanzee made the best beds. It may not be altogether +clear why the adult female was the best chambermaid of all. Her +efforts in bed making did in fact show a precision in tidiness that +was unequalled by any of the others. Usually in the evening, as the +strenuous play of the day subsided, all of the apes began to gather +heaps of straw. In the centre of each heap a chimpanzee would sit +quietly and begin to twist the ends of the straw together. This work +continued all around the edge until a natural nest, not unlike that of +the stork, was formed. The younger animals in their nest making were +less exact. They seldom made so neat a turning down of the outer edges, +but on some occasions, when they apparently took more pains with their +handiwork, their movements during the preparation of the nest were +exactly like those of the older females. Nests were often made during +the day in pure fun, and many different materials, such as string, +grass, branches, rags, ropes, and even wire, were collected for this +purpose. It was quite evident that in their nest-making activities the +younger chimpanzees imitated the actions of the older ones. + + +_Clowning and Masquerade_ + +Objects of many kinds interested these apes. They seemed particularly +fond of carrying quite a variety of rubbish about on the body in one +way or another. Nearly every day some of the animals began walking +around the playground with a piece of rope, a bit of rag, a blade of +grass, or a twig upon the shoulders. Some of them if given a bit of +metal chain would put it proudly around their necks like a necklace. +Bushes and brambles were often carried in considerable quantities +spread out over the entire back. In these actions they affected a +manner that revealed tendencies familiar to human masquerading in +grotesque or fantastic costumes. One of the chimpanzees contracted the +habit of carrying around empty preserve cans by grasping the lid of the +can between his teeth. All of this occupation was done as diversion +or entertainment, from which the chimpanzees derived much visible +pleasure. The clowning actions of these apes clearly held the attention +of those not actively participating in the performances, and many of +them, like little children, attempted to imitate the antics of the +leader. When dressed up in these various ways the chimpanzees often +displayed an almost impish self-important audacity, strutting about +among their companions or advancing upon them in a menacing way. One +of the older females, attired for play, would trot around in a circle +with several of the smaller animals following closely at her heels. +Sometimes the entire company playing in this fashion would march around +in a circle, one behind the other. The largest animal would stamp its +foot at each step, as though beating time for the parade. The other +animals followed suit by an accentuation of the marching movements. + + +_Manufacture and Building_ + +Not only did the chimpanzees acquire many ways for employing objects +which they encountered, but some of them actually went one step +farther. They manifested a degree of ingenuity in constructing special +implements for themselves. The results of this constructive industry, +it must be admitted, were relatively simple. On the other hand, there +can be no doubt that the chimpanzee does manufacture instruments, in a +modest way, which help him to gain his ends. One of the most talented +apes learned to fit a small piece of bamboo into the cavity at the +end of a larger piece. In this way he built a long bamboo pole, which +was especially useful for procuring food hung above his head and out +of reach. All of the chimpanzees ultimately developed some degree of +constructive or engineering ability. They actually became builders on +a small scale. This ability grew out of their learning to use boxes +in order to reach objects over their heads. Using one box led to the +advantage of piling one box on top of another and thus constructing +a tower. They were not all equally expert as builders. As might be +expected, the more quick-witted and alert members of the group learned +how to build first, and this they did entirely of their own initiative. +After they had built a tower of this kind, the long bamboo stick came +in handy as a means to bring the suspended banana to the ground. +Here two modes of solving a problem were combined--that of building, +and that of using the long pole. Building operations soon became a +favourite pastime; yet in spite of the fact that they were given every +opportunity they never developed an efficient labour organization. +However helpful united efforts may have been toward their ultimate +aim, the chimpanzees failed to realize the advantages of a mutual aid +society. There was doubtless a reason for their lack of intelligence +in developing higher efficiency in this respect. Almost invariably +their building operations were dictated by a desire to obtain food +that was out of their reach. Among the chimpanzees this goal was in no +sense a mutual interest. It was a matter of the utmost selfish concern +to each chimpanzee. So whatever advantage there might have been in a +division of labour, there was never a thought of dividing the spoils. +When the chimpanzees gravely assembled in the presence of a basket of +food hung up over their heads, they gazed about for proper materials +to use as tools in reaching the desired goal. One would bring a pole; +another would drag up a box. These were put in position preparatory to +constructing a tower. The building would then begin in earnest. When +the first stages of construction were complete several of the animals +at the same time would show great impatience to clamber up. Each one +of them acted as if either he or she were the sole proprietor of the +structure. Often, too, the box already in position would be snatched +away by some competitive group in the building industry and dragged off +to be used in the construction of a rival tower. This would usually +result in a wrangle among the architects. In fact, the entire company +of builders might come to blows over this infringement of property +rights. After the subsidence of these Babel-like controversies the +building would be resumed and the structure would continue to grow +in height until it became an object of ever-increasing excitement to +the assembled workers, each manifesting a keen desire to mount it. In +consequence of this highly individualistic competition and due to their +restless efforts, the tower would sometimes tumble over and the result +of their labours be destroyed. Then it was necessary to begin all +over again. Usually in this renewed effort only the more diligent and +patient of the chimpanzees adhered to the original purpose. The others +became interested in more trivial occupations. Eventually the tower +was finished, and the more diligent as well as the more patient of the +toilers quietly mounted to the summit of the structure and, either +with or without the aid of the pole, obtained the coveted bananas. +Sometimes, however, just when the diligent one was ready to reap the +just reward of his efforts, some member of the group endowed with +unusual athletic prowess rushed up stealthily and with great speed to +the top of the tower and seized the prize before the rightful winner +had time to protest or retaliate. In all of this building enterprise +there is something so fundamentally human, so reminiscent of modern +methods, that it seems inaccurate to class these reactions too rigidly +in the category of ape behaviour. + + +_Emotions of the Chimpanzee_ + +The chimpanzee, according to Professor Köhler, has a range of +expression of emotion even greater than that of the average human +being. The chimp shows his feelings by his entire body, not merely +by his facial expressions. It is his custom to jump up and down both +in joyful anticipation and in anger or annoyance. In extreme despair +or disgust, which the animal shows on slight provocation, he has the +habit of flinging himself upon his back, rolling wildly to and fro, +swinging and waving his arms about his head in a frantic manner not, +on the whole, very different from the way in which some non-European +races manifest their disappointment and dejection. The chimpanzee is +not known to weep, nor does he laugh in quite the human sense of the +term. There is something approaching human laughter in his rhythmical +gasping and grunting when he is tickled. While quietly watching objects +that seem particularly pleasing (and his greatest delight comes from +observing little children) the face of the chimpanzee, especially +around the mouth, has an expression not unlike a human smile. When +perplexed or in doubt, he has a way of scratching the surface of his +body, especially the arms, breast, or upper portions of the thigh. +It has not been stated that during these moments of perplexity he +scratches the head, as is the common human custom. He conveys his +meaning not only of emotional distaste but also of definite desires. +The expression of his wishes is in large part shown by direct imitation +of the actions desired. Thus, when one chimp wishes to be accompanied +by another, he gives the latter a nudge and pulls him by the hand. If +one chimpanzee wishes to receive bananas from another, he imitates the +movement of snatching or grasping accompanied by pleading glances. The +summoning of another chimpanzee from a considerable distance is often +accompanied by a beckoning that is very human in character. Their many +actions in all instances are characteristic enough to be understood by +their comrades. + + +_Surgical Interests_ + +The chimpanzee is especially prone to pay close attention to the wounds +or injuries received by his fellows. The motive of this attention may +scarcely be called mutual aid. The removal of splinters from each +other’s hands and feet is a favourite clinical operation. In this +pursuit the chimpanzee employs methods usually in vogue among the human +laity. Two finger nails are pressed on either side of the splinter, +which is thus elevated until it may be caught and removed by the teeth. +Professor Köhler himself, once having suffered from such an accident, +ventured to allow one of the chimpanzees to remove the splinter from +his hand. On perceiving the condition, the chimpanzee’s face at once +assumed an expression of eager intensity, and his attention became +concentrated in preparation for his surgical efforts. He seized the +hand, examined the wound, forced out the splinter with two somewhat +powerful squeezes of his finger nails, and then closely examined the +hand to be satisfied that his work was well done. + + +_Morals Among Chimpanzees_ + +There is much of interest in the experiences of another distinguished +observer, Dr. Charles F. Sonntag, formerly Prosector of the Zoölogical +Society of London, who has called attention to the fact that the +chimpanzee is said to be filthy in its habits. He observed that many +of these animals in captivity do not manifest such traits, nor do they +show any tendency toward immoral behaviour as has been claimed. It +seems unfortunate even to imply that such a delinquency as immorality +exists among chimpanzees or, for that matter, any of the lower mammals. +But since the point has been raised, it may be well to recall that +morals are of human making. They are designed to modify, to restrain, +or to prevent the development of certain animal tendencies which are a +human heritage from the great animal kingdom. If the chimpanzee in any +of its actions tends to depart from the code of morality established by +man in one part of the world or another, this can be no reproach to +the ape, since man himself has not yet been completely successful in +building up a system of restrictive laws to protect himself from the +devastations of his own animal inheritance. + +Professor Köhler, from his long studies of the chimpanzees, concluded +that these apes manifest intelligent behaviour of a general kind +familiar in human beings. Not all of their intelligent acts are similar +to human acts, but by means of well-chosen tests the character of +intelligent conduct can always be traced in the chimpanzee. These apes +differ among themselves just as much as people do, in their mentality +and intelligence. Some of them may be mentally deficient, just as +there are mentally deficient human beings. One remark of Professor +Köhler’s is a keen social criticism with a wide application to life +in general. He maintains that the tests designed for the chimpanzee +serve two purposes: First, they determine the intelligence of the +apes; and, second, they test the intelligence of the examiner. This is +eminently true in all intellectual contacts between human beings. It is +a fact that the chimpanzees stand out among all other animals in their +form, in their actions, and in their understanding. In these respects +they come much closer to the human standard than any other ape, with +the possible exception of the gorilla. All of these observations +agree well with the theory of evolution, and in particular with the +close relations existing between the growth of intelligence and the +development of the brain. + +Many other chimpanzees have been studied from time to time. The +conclusions drawn from them have been closely similar to those already +cited. Romanes some years ago studied the trained chimpanzee, Sally, +which was famous for her high degree of intelligence. Under training +this animal acquired the ability to count. She could draw a number of +straws to six or seven, and upon request would indicate with straws +the exact number she had been instructed to show. This achievement, +in combination with many other extraordinary performances, reveals +certain striking likenesses to man, particularly as to the degree of +the chimpanzee’s power to learn. + + +_The Chimpanzee’s Social Traits_ + +Others besides Professor Köhler are willing to give the chimpanzee +credit for unusual good-fellowship. All admit that he is a most +friendly creature. Often an affectionate attachment exists between him +and his owner or keeper. He is never loath to indulge in his clowning +performances to please and entertain his human friends. His actions +on these occasions have doubtless been the models for the ludicrous +mimicry of olden times now generally referred to as “aping.” In many +of the army encampments in Africa, monkeys and apes have been the +much-prized pets of the officers. It was not uncommon to find among +these pets the highly sociable chimpanzee. Frequently the officers +manifested much zeal and interest in training their charges and felt +a real pride in exhibiting them. Sometimes on gala occasions these +simian pets occupied places at the table beside their owners. They +partook in most approved style both of food and of drink. Not a +few of them have shown a distinctly human characteristic in their +strong liking for intoxicating liquors. The chimpanzee has always had +a decided penchant in this direction. At mess dinners and on other +occasions he not only manifested a keen liking for good wines but took +his share with the rest. Often he, like his human companions, rose to +hilarious heights. Often, too, it was necessary to lead him off to +bed in such a deplorable condition that he would appear next morning +with a shaky hand on his brow and that sad expression which plainly +told the consequences of festive revelry. One of these chimpanzees had +a particular fondness for afternoon tea and would join the officers’ +group at this time as a matter of course. His manners were altogether +agreeable. He acquired all of the airs essential to such occasions even +to certain banal chatterings. + + +_In Prophecy of the Human Brain_ + +If doubts should remain concerning the superior and almost manlike +capacities of the chimpanzee, these may be soon put at rest by +inspection of his brain. In this organ there are indications of the +means by which the chimpanzee has acquired his new and extensive +powers of learning, his greater understanding, his higher capacity for +adjustments to life, and his many reactions which are so nearly human. + +Every sense department in the superbrain has shown pronounced +improvements. A survey of the chimpanzee’s brain shows it to be a +mechanism better organized for the purposes of efficient output than +that of other apes and monkeys. It is a larger brain. It also has a +greater richness in grooves and convolutions showing that its capacity +for developing brain power has been much increased. The groove of +Sylvius has been tipped backward in consequence of expansions in the +department of hearing and the department of body and contact senses. +In the department of hearing (the temporal lobe) the convolutions are +more complex than in any other lower apes or monkeys. In fact, the +entire pattern of coil arrangement in this part of the superbrain +is similar to that seen in man. It has, perhaps, a simpler design, +but the essential features of the pattern may all be identified. In +the department of sight the same principle of expansion has been at +work. The convolutions in the occipital lobe have increased both in +number and complexity of arrangement. There are more grooves and more +convolutions in this region than we have yet encountered. Such also is +the case in the department for body and contact senses (the parietal +lobe), in which the grooves and convolutions manifest an arrangement +identical to that of man. The lesser brain, lying as it does tucked +away beneath the occipital pole of the superbrain, also shows marked +increase in size, so that the subsidiary department essential to +postures of the limbs and body, and also to balance, has kept pace +with the superbrain. Appraised on the value of its great working +departments, a brain like this reveals the manner in which progressive +development has advanced. + +The organization for transacting the functions of hearing has been +greatly improved, if we judge by the enlargement of the temporal lobe. +Furthermore, it appears that certain sub-departments for handling +these transactions have been established. They doubtless have to do +with a better filing system for auditory impressions and especially +for correlating the impressions of things heard with similar records +of things seen. This method of cross reference produces a better +understanding of all objects encountered in the surroundings. A +practical illustration may assist in visualizing the manner in which +such associations operate. If in their home life the chimpanzees +are suddenly startled by the report of a gun, which they have never +heard before, the entire family may be greatly perturbed by the +harsh and unfamiliar sound. The sound alone might be startling and +disagreeable, but the sound cross referenced by the sight of the +hunter and gun comes to mean peril. Instances of this kind might be +multiplied to show how essential to success in life this system of +cross reference is. In fact, it is the amplification of this system +that underlies our progress as individuals or as a race. The structural +signs of this progress are to be found in the region of the brain +that we have been discussing. We may recognize them in the increased +number of convolutions which provide for better development of brain +power. Equally pronounced are the advances that have taken place in +the organization of body and contact senses. This department lies +immediately above the Sylvian groove in the parietal lobe. It receives +all communications transmitted from the outside world by the sense +of touch and by the various movements of the body. The convolutions +in this region indicate a highly organized department which we might +expect in view of the remarkable performances of the chimpanzee. +Walking a tight rope, eating his food with a certain degree of good +manners, drilling to music, or driving an automobile, the chimpanzee +clearly demonstrates how expert he has become in the use of his hands +and feet. His cleverness depends upon his ability to sense the things +he touches and to appreciate the finest grades of motion made by his +arms and legs. In addition to this high degree of sensing in his hands, +he has also acquired greater capacity for appreciating movements and +postures of his entire body. Unless the chimpanzee had this expanded +department for body and touch senses, it would be impossible for him +to learn many of the performances which he does so skillfully. He also +would be unable to apply this skill under the direction of his masters +or according to the dictates of his own wishes. It is not difficult to +understand, therefore, why all the great departments of the senses have +increased so much in size in the chimpanzee. Obviously, by amplifying +and refining the raw materials received as sense impressions, the +output seen in the chimpanzee’s behaviour has been correspondingly +amplified and extended. The significance of growth in the parietal, the +occipital, and the temporal lobes in this light becomes clear. + +One important detail in the superbrain of the chimpanzee we have not +yet considered. It will be recalled that the central groove is one +of the salient landmarks in the brain. Its outstanding importance +arises from the fact that it is the boundary line of the frontal +lobe. All of the territory lying in front of this groove represents +the last acquired department of the superbrain, the one having the +highest authority. It is here that all of the highest brain functions +are located. Judgment and reason are included in this list. But to +these should be added the ability to profit by experience in the +better guidance of life, the upbuilding of personality, and the +proper adjustment in all courses of action requiring initiative, +insight, restraint, and self-control; and, finally, recognition of +responsibility and appreciation of opportunity. + +The frontal territory in the chimpanzee is more extensive than in the +orang or any other of the lower apes. It shows an additional amount of +convolution. The frontal coils for producing the brain power of this +highest department have attained a development not far below that of +man. The counterpart of each human convolution is present, the only +difference being that each individual convolution in the chimpanzee is +less complex than in man. These facts about the frontal lobe, which we +must regard as the permanent headquarters of the chief executive of +the superbrain, are in harmony with what Professor Köhler and other +students of animal psychology have told us about the chimpanzee’s +intelligence. Man’s frontal lobe is a highly complex facsimile of the +chimpanzee’s, just as human intelligence is a more complex development +of the higher mental powers. + +These improvements in the superbrain are borne out by both the +bridge and the pyramid. The bridge, recognized as a reliable index +of intelligence, has the value of .400 in the chimpanzee, a rating +much above the orang or any of the lower apes already considered. The +pyramid also shows a corresponding increase, having a value of .172, +and thus indicating a greater development in skilled acts and in the +voluntary control over the actions of the body. These two structures +show that the superbrain has, in fact, become a more efficient governor +for the guidance of a larger, a more complex, and a more effective +machine. Every detail in the brain of chimpanzee clearly demonstrates +the marked advance that has been made in the steady upward climb. We +are able to identify all of the chief features characteristic of the +human brain. + + + + +CHAPTER X + +ALMOST HUMAN + +THE BRAIN OF THE GORILLA + + +The largest member of the ape world is the gorilla. There is much +dispute to-day concerning the place he occupies in relation to man, +and also as to what rating his intelligence deserves. Neither of these +questions can be settled at present. His case, in fact, requires much +more study than has yet been given to it. Recently the gorilla has +been befriended by several famous African explorers like the Bradleys +and the late Mr. Carl Akeley. They have given him a rather favourable +recommendation as an inoffensive and retiring animal. In spite of this +vindication, however, most persons who have any acquaintance with him +regard the gorilla as a dangerous, savage brute. Standing upright, he +is nearly as tall as the average man. Sometimes his height reaches six +feet, and often the adult male attains the great weight of nearly four +hundred pounds. + + +_A Superlative Fighting Machine_ + +The body of the gorilla is stout and large. His legs are short but +his arms are extremely long. When standing erect the tips of his +fingers reach to about the middle of the leg below the knee. His huge +and grizzly head, flat, broad nose, prominent muzzle, large mouth, +very large canine teeth, and protruding ears all give the animal a +terrifying appearance. + +The manner in which he rises on his hind legs and makes the forest +reverberate with his roars when attacked is one reason why the gorilla +is considered the most savage of all beasts. His hands are large and +thickly covered with black hair on the back. The palms of the hands +have no hair. They possess many grooves and markings with strong human +resemblances. The thumb is somewhat short for the size of the hand, +but is thick and bears a broad nail. The animal’s body as well as the +head up to the brow line is covered with thick, black, shaggy hair. The +skull is massive and heavy. The eyes are surmounted by a heavy ridge +of bone, and a thick bony crest extends from the bridge of the nose to +the back of the skull along the middle of the head. All of these bony +structures provide the gorilla with a most effective fighting helmet. +The massive head, the short neck, the powerful arms, and the savage +teeth create the impression of a superlative fighting machine--a sort +of dreadnaught. But this machine has one inherent weakness. The feet +and legs are inadequate for a finished fighter. The gorilla is able +to assume the upright position and walks thus in an awkward manner, +using the arms in balancing. In the main, however, he goes on all +fours, especially when making speed through the underbrush or climbing +among the trees. He rises upon his hind legs largely for purposes of +inspection in order to make a survey of the surrounding territory. + +Many species have been identified. They all live in Africa. One variety +inhabits the Gaboon in West Africa. It also extends into regions of +southern and northern Cameroon, near the border of the French Congo. +This variety of gorilla is especially adapted for forest life. Another +type, sometimes spoken of as the mountain gorilla, inhabits mountainous +localities in the Belgian Congo. + + +_The Gorilla’s Ancient Disrepute_ + +The gorilla has been long and unfavourably known to mankind. Ancient +rumour of him spread abroad many unsavoury reports about his savage +disposition. In the Fifth Century B. C. gorillas were first spoken of +as wild, hairy men living in Africa. The Carthaginian Admiral Hanno, +in his famous voyage to the Pillars of Hercules, appears to have been +the first white man to encounter them. He and his comrades unexpectedly +came upon a group of these wild people. All of the men fought so +savagely that they made their escape, but Hanno and his friends were +able to capture three of the women. These females were so ferocious +and unfriendly that it was necessary to kill them. Their skins were +preserved, taken to Carthage, and there placed in the Temple of Juno, +where they were held sacred until that city was destroyed. + +The famous explorer, Paul Du Chaillu, in his _Explorations and +Adventures in Equatorial Africa_ describes the gorilla as gregarious. +He found them going about in companies of eight or ten. Sometimes the +older males become superannuated. Then they live solitary lives apart +from these small communities. When grown old they appear actually +grizzled with age, and the hair, which in youth is black, becomes +almost white. Du Chaillu was probably the first European to kill a +gorilla in its native forest. His description of their habits was +thought to be an exaggeration, but later information largely upholds +his opinion. He believed that the gorilla did not, as often claimed, +lurk in the trees just above the roadside in order to reach down with +his great arms and snatch up the unsuspecting passer-by. He discredited +the ancient story that these animals attack elephants and beat them +to death with sticks, and that they carry off native women to devour +them in the depths of the forest. He did not even believe that the +gorilla built itself houses or nests from twigs among the trees, or +that large bands of them made attacks upon men whose homes were in the +neighbourhood of the forest. Du Chaillu reported that the gorilla lives +in the loneliest portions of the dense African jungle. It is seldom +found in the same place two days in succession. It prefers deep wooded +valleys or rugged heights and roams about over a large area in search +of food. It consumes a large amount of food, such as pineapple leaves, +berries, wild sugar cane, and other vegetable matter. The animal sleeps +sitting on the ground with its back against the trunk of a tree, and +when full-grown seldom ascends high among the branches. The young sleep +in the trees, and possibly the females may occasionally do so. + + +_Like Some Monster of a Nightmare_ + +In spite of their reputation to the contrary, the gorillas are in +reality shy. The female will run to shelter at the first sound of +alarm, carrying her young one with her. The male, however, is less +hurried in his retreat. In fact, he seems to act upon the theory that +the best defense is an attack. He rises up on his hind legs for a +moment, showing his savage face among the underbrush. Then, glaring at +the intruder, he begins to beat his chest with his closed fists, at +the same time uttering a deep, terrifying roar. This sound begins at +first as several loud barks like those of a dog and then changes to a +deep-throated growl, which is emitted with redoubled force, causing +echoes in the forest like distant thunder. Du Chaillu said that the +horror of the animal’s appearance at this time is beyond description. +It seems like some monster of a nightmare, an indescribable piece of +hideousness. + +In walking, the gorilla waddles from side to side as he proceeds upon +his hind legs. Meanwhile, in order to balance himself, he swings his +great arms at his sides, which makes him appear more determined and +awe-inspiring. When attacking, his features are distorted by hideous +wrinkles, and his lips are drawn back revealing long fangs in the +powerful jaws by which a human limb could easily be crushed. + +The celebrated African explorer, Mr. Akeley, has pointed out that there +is no difficulty in shooting the gorilla. In fact, against modern +firearms this animal is as defenseless as a crippled woman. Such +hunting is thoroughly distasteful and seems to be an atrocity closely +akin to murder. It was due to Mr. Akeley’s efforts that the King of +Belgium recently set aside a large territory in the Congo as a gorilla +sanctuary, in which all hunting of this animal is prohibited. Here, in +the vicinity of the three extinct volcanoes, Mt. Keno, Mt. Karissimbi, +and Mt. Visake, Mr. Akeley hoped that a biological station might be +established for the further study of the gorilla’s behaviour. In this +sanctuary, now known as Albert National Park, he believed it would +be possible to gain a footing on close and intimate terms with this +gigantic ape. Mr. Akeley was convinced that the gorilla’s reputation +for ferocity was greatly exaggerated, and that the animal was actually +a timid and retiring beast. This new estimate of the gorilla’s +disposition gives encouragement to the expectation that in time this +fast-disappearing offshoot of the prehuman stock may furnish its full +testimony concerning the evolutionary process. + + +_Training the Young Gorilla_ + +In adult life the gorilla is untamable. If captured young, as much may +be done with it as with many other apes in captivity. The following +account of a gorilla’s life in civilization, given by Miss Alyse +Cunningham, of London, testifies to this fact. It is the story of the +young gorilla called “John Daniel the First.” The record was made by +Miss Cunningham herself. At first she had no fancy for this animal; in +fact, she felt rather a dislike for anything in the shape of a monkey +or an ape, but she soon became interested in the young gorilla and took +his education seriously in hand. The animal was presented to her by her +nephew, Major Penny, shortly after the end of the Great War. He was +much interested in apes and bought the gorilla with the idea of seeing +how much mentality it possessed and how much it could be developed. +John Daniel was captured when very young in the French Gaboon country +and came to England when he was about three years of age. Major Penny +first saw the young gorilla on exhibition, during the Christmas +holidays, in a large show window of a well-known shop in London. The +animal attracted much attention and large crowds gathered daily to +watch him. As a dry-goods advertisement he was a splendid investment, +but unfortunately at that time he was suffering from rickets. With +the severe changes of weather in the Christmas season he contracted +an attack of influenza. On this account his owners were compelled to +retire him from his advertising post and found themselves at their +wit’s end to know what to do with this sick infant gorilla. When he was +finally sold to Major Penny his original owners did not think he would +survive for very long. In this respect their calculations went astray. +Miss Cunningham took the sickly gorilla, nursed him as she would a +child, brought him through his influenza, and so successfully cared +for him that during the next three years he reached the weight of 112 +pounds and the height of three feet four and a half inches. Meanwhile, +he acquired many of the habits and adjustments necessary to fit him as +an interesting if somewhat unusual member of the household. + + +_John Daniel the First_ + +We are indebted to Miss Cunningham for the excellent account of his +life, which indicates the extent to which this great ape may be +trained and educated. Little John, immediately after his recovery from +influenza, began to show some singularly childlike emotions. He was +gentle and affectionate in response to the tender care he received. But +he became too much attached to his new and kind friends. His devotion +in this respect created some difficult situations in the household. +If he were left by himself at night he would shriek from fear and +loneliness. Perhaps he remembered the long and cheerless nights when +he was a Christmas exhibit in the department store. In any event, +Miss Cunningham was forced to treat him just as she would any little +child. She coaxed and soothed and petted him until she had allayed his +fears. Then he would become quiet and fall asleep. But even this was +not sufficient. It soon became necessary to place her nephew’s bed +in the room adjoining the cage of the gorilla. Apparently he craved +companionship of some kind and at length became quite happy under this +new arrangement. + +John soon began to grow and to put on weight. He gradually got over his +rickets. At first he was taught to be clean in his habits by a system +of rewards and punishments. At the end of six weeks he was thoroughly +housebroken. At this time he was taken out of his cage and allowed the +freedom of the house. Thereafter, John would always run upstairs to the +bathroom of his own accord. He would turn the knob of a door and took +pains to see that he always left it closed behind him. He showed strong +likes and dislikes in the matter of food. There was one feature that +always puzzled Miss Cunningham in this respect. Generally speaking, +John was not a thief. He manifested average honesty, but when it came +to food he much preferred to steal it than have it given to him. It +was difficult to understand the motive underlying this course of +action. There were some things about it that seemed to indicate a real +satisfaction derived from stealing, due, perhaps, to an outcropping of +his native cunning. Perhaps it was the consequence of a well-recognized +quality of natural aloofness characteristic of the gorilla in general +that made John Daniel averse to receiving favours from others. He would +always avoid any food that had been exposed to the air for long. He +was particularly fond of oranges and apples, but would never eat them +if they had been cut a few hours. John had what almost amounted to a +passion for eating roses. The more beautiful they were, the more he +seemed to like them, but nothing would induce him to eat faded roses. +Nuts he did not much care for, although at times he showed a liking for +walnuts. A cocoanut was always a problem to him. It was most amusing to +see how he went about this problem. He understood that it was necessary +to break the cocoanut. First he would throw it upon the floor, but +failing to break it this way he would finally bring it to one of the +members of the family with an appealing look for help. If given a +hammer he would use it viciously on the nut, but never effectively. +After several failures John would take the nut and the hammer to +someone, indicating what he wanted. + + +_John’s Social Behaviour_ + +John had a good understanding of tools, almost too good, in fact. In +consequence, hammers, chisels, and saws were kept in hiding, and if +John happened to find them he was apt to indulge in a somewhat ruthless +carpentry on the household furniture. From his babyhood, and while he +was growing up, he was always fond of people. He liked to have them +come to visit him at his home. Far from being timid and shy, he was +quite the reverse. Whenever there were visitors he always liked to show +off, just like a child. He would take the visitor by the hand and lead +him round and round the room. This amused John greatly, and if his +guest responded playfully all went well, but if there was any sign of +nervousness or fear John took an impish delight and would run by the +visitor, giving him a smack on the leg. Then, perching himself on a +chair, he would grin foolishly at his own mischief. This was the only +blemish on his company manners, and he always appeared a bit shamefaced +when rebuked for such misbehaviour. He did not, however, go the length +of making apologetic overtures to his offended visitor, but kept +himself aloof with an air of injured innocence. + +Miss Cunningham had few misgivings about John when she had company in +the home. He was always very obedient to her and seemed to recognize +that her wishes were law. It hurt him apparently to be guilty of +any act which caused her displeasure, and while sometimes he would +perpetrate some mischief on the sly he would always be on his best +behaviour when he felt Miss Cunningham’s eye upon him. His table +manners were rather good. He always sat at the table, and when the +meal was ready would pull up his chair to the designated place. He +never cared for great quantities of food, and his actions at table +required little, if any, more reproval than did an ordinary child. He +was especially fond of drinking water from a tumbler. He always took +afternoon tea with the family. He had a particular liking for this +beverage and with it would eat a thin slice of bread with plenty of +jam. He also liked his demi-tasse of coffee after dinner. The family +estimate of him was generally high. He was regarded as the least greedy +of all the animals that had ever come under the observation of his +owners. He would never snatch for anything at the table, and he always +ate slowly. He was accustomed to drink large quantities of water, +which he got for himself whenever he wanted it by turning on the tap. +Strangely enough, he always turned off the water when he had finished +drinking. + + +_A Gorilla with a Sense of Humour_ + +John Daniel had a very good opinion of himself. He was quite well +poised and self-contained. Nothing seemed to ruffle him, and he could +amuse himself in simple ways by the hour. He seemed to believe that his +own estimate of himself was shared by others and appeared confident +that everyone was delighted to see him. Often he would stand on the +window sill and throw up the shade. In a short time a large crowd +would collect on the street below to watch this unusual sight at the +window. He enjoyed such publicity immensely and would stand watching +the people for a long time. Once in a while, if the crowd grew very +large, he would pull the shade down deliberately in their faces and run +away shrieking with laughter, in a way which seemed to indicate that +he was conscious of having perpetrated a huge joke upon his audience +outside. Of course, this entire reaction and the motives underlying it +are open to several interpretations. Skeptics will say that the version +here given endows the gorilla with attributes more human than he could +possibly possess. However that may be, those who actually observed +these performances were impressed by the fact that John Daniel did act +in a seemingly human manner. + + +_Fondness for Little Children_ + +John was especially attached to Miss Cunningham’s three-year-old +niece, who often came with her mother to stay at the house. They +would play together by the hour. The gorilla seemed to know just what +this little girl wanted him to do. If she cried for any reason, when +her mother came to pick her up, John would give the mother’s hand a +nip with his teeth or slap her with the full weight of his palm, +apparently thinking that she was the cause of the child’s grief. One +day Miss Cunningham was dressed for going out, and John Daniel wished +to sit on her lap to bid her good-bye. It chanced that her gown was a +light-coloured one, and she pushed him away, saying that she feared he +might soil her dress. Poor John was deeply distressed. At once he lay +down on the floor and cried like a baby for a moment. Then he looked +around the room, found a newspaper, laid it on Miss Cunningham’s lap, +and climbed up on it. This was the cleverest thing he had ever done. +Those who saw it said they would not have believed it had they not +themselves been present. + + +_Like a Child in Play_ + +John Daniel apparently could stand a good deal of cold weather. He +would often climb out on the roof when the thermometer was below the +freezing point. He did not seem to mind how cold it was so long as he +could come back into a warm room when he wanted to. Then he would go +directly to the fire, rub his chest, and sit down with his feet cocked +up on the fender. Exercise was necessary to keep him in good health, +and John got much of this by playing hide-and-seek with Major Penny. +In the morning before breakfast and in the evening before dinner the +Major would run up and down stairs, in and out of all the rooms. The +game appeared to delight the gorilla, who would giggle and laugh while +being chased. He never took any chances about going into a dark room, +however. Invariably he would make sure to turn on the light first. + +It was his habit to retire each night at eight o’clock, and it was not +necessary to tell him to do so more than once. He had his own little +room adjoining that of Miss Cunningham’s nephew, in which he had a +spring bed of his own, with blankets and pillows. At night he would +get up out of bed by himself, go back to bed, and pull the blankets +up over himself quite neatly. One of John’s greatest pleasures was to +stand on the top rail at the foot of the bed and jump on the springs, +just like a little child. He was never taught any tricks, but simply +acquired knowledge by himself. In the summer time John was taken by +train to the family’s cottage in the country. He occupied his seat in +the railway coach like any other passenger, without so much as a chain +around his neck. When out of doors the broad fields and open country +seemed to terrify him, but he was singularly happy and contented in the +quiet garden or in the woods. He seemed to fear full-grown sheep, cows, +and horses, but colts, calves, and lambs attracted and amused him. It +seemed to those who cared for him that he recognized youth and was +sympathetically drawn to it. + + +_John Becomes Famous_ + +As the years passed he became more devotedly attached to the family. +If left alone he would make a great noise, shrieking and crying. This +tendency increased, so that after three years it was necessary to make +some other arrangement for him. Through a misunderstanding which his +owners have always regretted, John was sold to a circus. He was taken +across the Atlantic to New York. Here, after a month’s separation from +his devoted friends during which time he refused to take food and +showed every sign of real homesickness, he died in the tower of the old +Madison Square Garden, in April, 1921. + +Many of the New York daily papers published a notice of this remarkable +ape’s death, telling how the gorilla, John Daniel, homesick and +disconsolate without those who had befriended him, died of a broken +heart. The skeleton and taxidermic preparation of this gorilla, who has +contributed so much to our knowledge and understanding of the great +apes, may be seen in the anthropoid collection in the American Museum +of Natural History, bearing the label “John Daniel.” + + +_A Gorilla at Afternoon Tea_ + +As an interesting sequel to this history of what appears to be the +first gorilla raised under the conditions of such intimate domestic +life, it may be added that Miss Cunningham secured another gorilla, +which she called “John Daniel the Second.” John Daniel the First was +a little over six years old when he died and was then less than half +grown. These two great apes resembled each other closely in their +emotional reactions and in their responses to training. Both were about +of the same age. John the Second was perhaps a less likable individual +and had a disposition more in keeping with the ancient reputation +of gorillas. Several years ago, while he was visiting in New York, a +number of scientists were invited to have afternoon tea with him at a +certain fashionable hotel. On this occasion the troglodyte host was +found seated in a comfortable chair. He displayed much gravity and +apparent enjoyment as he drank from a cup of tea. During the course of +conversation John the Second was for a moment not the actual centre +of attention. Suddenly he dashed across the room with unbelievable +swiftness and attacked one of his visitors with repeated rapid blows of +both fists in the neighbourhood of the solar plexus. Just as quickly +he hopped over the foot of the bed and from this point of vantage +watched the discomfiture of his guest. A moment later, when less +sharply watched, he hurled his full weight in most approved football +style against a distinguished professor of zoölogy, who, as a result, +was thrown from his chair. In the intervals between these presumably +playful diversions this powerful gorilla sat quietly. Yet, in spite +of his innocent demeanour, one was suspicious that he was casting +about for the next piece of mischief that he might perpetrate. There +was a degree of roughness and sudden strength in the playfulness of +this young gorilla that afforded some idea of the terrific power these +animals must possess when full grown. + +The attractive prospect of a biological station in Africa, as +suggested by the late Carl E. Akeley, for the study of the gorilla is +inspiring. It should be possible under these circumstances for one +scientifically inclined to saunter into the jungle of a morning, call +to some particularly promising gorilla, and with the troglodyte spend +many profitable hours in biological study. If the full-grown gorilla, +however, is anything like John Daniel the Second, this studious +occupation might not prove so simple. Indeed, it seems probable that +only the most hardy of human adventurers will ever enjoy the privileges +of anything approaching a familiar acquaintance with these giant apes. +Such adventurers may live to report that the great brutes have acquired +no marked degree of gentleness even in their own gorilla sanctuary. + + +_The Art of Capturing Young Gorillas_ + +On a number of occasions young gorillas have been captured alive. Mr. +Ben Burbridge, using some clever tactics, has succeeded in capturing +several small gorillas. The approved style of such hunting is to lure +the young animal away from the older gorillas; then, grasping the +throat, force it to the ground until helpers arrive to slip a stout +bag over its head. On one occasion Mr. Burbridge succeeded in artfully +luring a gorilla from the rest of his family. He at once proceeded to +seize him in the usual manner. Immediately he realized that he had +caught a tartar. The young gorilla was much stronger than any man, and +grasping both of Mr. Burbridge’s hands he forced them into his savage +mouth. Nothing but iron nerve and quickness of wit would have saved a +man under these circumstances. Realizing his inability to overpower the +gorilla or free himself from its vise-like grip, Mr. Burbridge did the +only thing left for him to do. He thrust his hands down the animal’s +throat as far as they would go. Several natives finally succeeded in +overpowering and binding the young giant. The first burlap bag put +over his head he split asunder like a piece of gauze. At length he was +bound and carried off to camp. But this young monarch of the volcanic +mountain sides would not accept captivity. He was unapproachable and so +actively hostile that he soon died. Later, Mr. Burbridge succeeded in +capturing and bringing home to Florida a small female gorilla, weighing +sixty-five pounds, which he called “Congo the Second.” + + +_Professor Yerkes Studies “Congo the Second”_ + +We are extremely fortunate that this gorilla has been studied by +Professor Yerkes, who in a book recently published, called _The Mind +of a Gorilla_, has given us another of his brilliant works on animal +behaviour. This is a most readable account of Congo’s actions, and +those who wish further information will derive much pleasure from +Professor Yerkes’s story. All of his observations are illuminating and +helpful in understanding the brain of this great troglodyte. + +The mountain gorilla, as Professor Yerkes points out, is built for +strength rather than speed. Congo, although still in her childhood, +and weighing only sixty-five pounds, was amazingly strong. She could +lift weights and overcome resistances that required the full strength +of a grown man. In her play with a young Airedale terrier she became +so rough that the dog finally avoided her. Her climbing among the +trees, about which she seemed eager, was scarcely any better than that +of an active small boy. It was easy to outrun her and throw her off +her balance. The tremendous strength of the gorilla must, therefore, +be looked upon as the real secret of his success in life. Without this +strength he probably would not have survived, since he has neither the +skill in climbing nor the speed upon the ground to escape his deadly +enemies. His deadliest foe is the leopard. This stealthy and powerful +cat often steals up to a gorilla family and snatches away the little +ones. The gorilla’s sole defense against the leopard is his gigantic +strength. If at present this great ape is threatened with extinction it +is because his natural enemies are increasing in number. Man with his +modern equipments must be listed among these hostile contemporaries. +For ages the struggle between the gorilla and his enemies in the jungle +has been going on relentlessly. The great ape has been able to maintain +that margin of superiority which permitted his kind to come down into +modern times. + +Professor Yerkes devised a series of tests for determining the mental +capacity of the young gorilla, Congo the Second. These were arranged in +several groups such as the following: + +1. The use of the stick as an implement. + +2. The use of simple mechanisms showing adaptive ability. + +3. The uses of boxes and piling boxes. + +4. Tests for memory. + +5. Observations of social relations. + +6. Study of emotions and incentives to action. + + +_The Mind of a Gorilla_ + +In all, twenty-four tests were employed in the experiments to fathom +Congo’s mind. Among them were the stick used as an implement, a +buried jar of food, food suspended and made accessible by using the +stick, food suspended and made accessible by piling boxes one on top +of another, the use of hammer and nail in imitation of a man using +the same implements, the mirror test and the animal’s reaction to +the looking-glass. Professor Yerkes carried on his studies through +a number of weeks on two different occasions. The first series was +conducted in January, 1926, and the second series, largely repeating +the conditions of the first, in January, 1927. During this time the +little gorilla had grown and prospered. She had doubled her weight in +twelve months and she manifested many changes in her behaviour. In +the first place, she had become somewhat destructive, although when +she first came to Shady Nook in Florida this was not the case. Her +curiosity had increased as had also her powers of imitation and her +emotional expressions. She was much more self-reliant and likewise more +coöperative. She showed a very considerable improvement in her ability +to solve the problems of the several tests given to her. In using +the stick she manifested greater cleverness and adaptability, with +some indications of real insight into the situations that confronted +her. There were signs also that she had gained a greater degree of +adaptability in the use of simple mechanisms. These appliances in her +earlier tests baffled Congo, but upon repetition a year later she not +only gave evidence of memory concerning the tests but also had more +ability in solving the problems which she had previously failed to +master. She showed much improvement, particularly in piling boxes one +upon another. Certain memory tests, which were unsuccessful in January, +1926, were quite successfully performed in January, 1927. Heretofore, +no animal except man has been capable of correct response in these +particular memory tests. Congo’s success possibly demonstrates the +existence of a mechanism in the gorilla brain that is possessed by the +most highly organized animals only. It is this mechanism, doubtless, +which distinguishes man and the great apes from all other mammals. +Buried food tests also demonstrated an ability to remember after +intervals of one or two days. Congo’s emotions likewise had changed. +At first she appeared aloof, independent, and inexpressive. She still +remained reserved, and although playful she was highly self-controlled. +Her emotional expression by voice, face, and attitude was rare, and +seldom appeared in response to definite provocation. Her incentives +and motives seemed much more complex than in lower animals, like rats +and guinea pigs. Congo was moody, having her good days and bad days in +doing the tests. The inducements offered her to perform certain acts +did not have the same certainty that they have with lower animals. In +her social relations she was extremely simple. She apparently gained +an increased interest in those with whom she was familiar and also with +strangers. She enjoyed visitors and acted in a limited way to entertain +them. Seeing herself in the looking-glass, she had a marked interest +in her image. In the second series of tests her interest in the mirror +seemed more intelligent than the first. In sexual interest Congo showed +a marked development. At first she manifested nothing resembling +sex play, but in the course of the year this became evident in her +relations with her dog companions and other objects. Ultimately she had +a decided preference for the male dog. + + +_Mental Comparisons of the Great Manlike Apes_ + +Professor Yerkes’s comparison of the behaviour of the three great apes, +the orang, the chimpanzee, and the gorilla, is particularly interesting +and important. He carefully guards his statement by acknowledging that +these are rough comparisons based on the intimate study of only a few +individual apes. The physical differences between these anthropoids may +have a definite bearing upon their mental characters. The chimpanzee +is well but lightly built. The orang, in contrast, is loosely built, +with arms that seem much too long and liable to be in the way. The +gorilla is stocky, somewhat clumsy, but of impressively strong build. +The general disposition of these three apes varies somewhat according +to their physiques. The chimpanzee is sanguine, buoyant, alert, and +snappy. The orang-outang is melancholy and taciturn. The gorilla is +reserved and aloof almost to the point of manifesting a superiority +complex. In their attitude toward others and things in general this +same difference is observed. The chimpanzee is preëminently a leader +in playfulness and invention of ways to amuse himself. He is quick, +impulsive, energetic, and comical. He has much enthusiasm and optimism, +all of which makes him the showman’s prize. The orang is more slow +and cautious, with little impulsiveness and no show of optimism. He +seems more stable and dependable than the chimpanzee. He is certainly +more readily depressed and discouraged than his livelier cousin. The +gorilla is calm, reserved, cool, and calculating. His disposition +is quite the opposite of that of the chimpanzee. The terms sullen, +morose, ferocious, and unrelenting did not, however, apply to Congo, +who was placid, self-dependent, and usually superior to the incidents +of her artificial life in captivity. In curiosity the chimpanzee heads +the list. The orang is a close second. The gorilla may be stirred to +curiosity, but under such circumstances usually acts as though he +considered himself superior to such childish indulgence. The manner +and methods of learning in these three great apes are remarkably +interesting. In learning by imitation from man, the chimpanzee has +a long lead. The orang is not entirely unsuccessful in this matter, +but the gorilla, especially as typified by Congo, shows an actual +resistance to learning by imitation of man. The ability to acquire +new habits and adjustments to life by means of trial and error +shows that the great apes rank as follows: Chimpanzee first, orang +second, gorilla third. Learning by ideas, experience, insight, and +understanding seems to reverse this order and puts the gorilla at the +head of the list. + +Professor Yerkes appears to think that, as compared with chimpanzees +and orangs of like age, Congo was remarkably slow in adapting herself +and was more limited in initiative, originality, and insight. He +concludes that the general tendency to rate the gorilla in a mentally +higher class than the chimpanzee or orang finds no support from his +study of Congo. He also believes that conclusions based on a single +specimen of this great ape are not sufficient to determine the mental +rating of the gorilla. This animal, like the chimpanzee and the orang, +indeed like man himself, has great individual variations in mental +development. + +Such records as those of John Daniel, First and Second, made by +observers little trained in the technical methods of behavioural study, +must of course be accepted with some reservations. Viewed in the light +of Professor Yerkes’s studies on Congo, they do afford an illuminating +picture of the gorilla’s mental capacity, disposition, and ability to +learn. To say the least, in all of these qualifications the largest +of the great apes is strikingly human. Its brain, which weighs and +measures more than that of other apes, is in many respects nearer to +the brain of man. In the gorilla’s brain it is possible to discern +the process by which the progressive development of this organ has +made great strides. All of the landmarks of the superbrain are more +distinctly human in their arrangement and disposition than in the +chimpanzee or orang. If the chimpanzee’s brain is a human miniature, +the resemblance to man in gorilla has become still more striking. The +position of the Sylvian groove and of the ape groove marks the boundary +of the two great departments of sight and hearing. In the gorilla +both of these have increased the area for radiating brain power. The +convolutions in both of these regions bear a close resemblance to those +of the human brain. This similarity is likewise true in the department +for body and contact sense, where the convolutions have increased in +complexity as well as in relative size. The central groove forms the +boundary for a well-defined frontal lobe. If it were possible to make +a measurable contrast of this permanent headquarters for the higher +faculties in gorilla to that of chimpanzee, it seems fair to say that +the gorilla would show some slight advantage. This advantage may +account for the gorilla’s greater reserve, which in some ways indicates +a more mature attitude toward life, especially when compared to the +restless and more childlike behaviour of the chimpanzee. + + +_Secret of the Gorilla’s Survival_ + +Professor Yerkes would perhaps be unwilling on the strength of his +studies to admit any measurable degree of superiority on the part of +the gorilla’s mentality over the chimpanzee. Unquestionably this is a +proper point of view in the light of those great apes which have been +available for experiment and investigation. In the main, such gorillas +have been both too young and too few in number to permit any just +estimate of their real ability. One fact in their history does speak +forcibly in behalf of their mental superiority over all other apes. In +form and physique the gorilla occupies an intermediate position. He is +not well adapted for great successes living upon the ground. He is too +heavy to capitalize the full advantages of living in the trees. Added +to this is the fact that he is both slow and clumsy. His one physical +asset in the struggle for life is his gigantic strength. By means of +this advantage he has been able to meet all comers of the wild, to +contend with such deadly enemies as the leopards and other members +of the great cat family. He has eked out an existence in a territory +filled with all manner of hazards. Yet in spite of his handicaps he has +not only held his place in nature but he has kept his line a vital and +going concern with all the increasing odds against him. This success +in adjustment must depend upon something more than mere chance. We are +perhaps fair in assuming that added to his chief asset of brute-like +strength there have been certain superior mental qualities derived from +a superbrain and particularly from a frontal lobe which surpassed that +of all his animal competitors. + +The index of his powers to adjust himself to a strenuous life is shown +by his bridge (_pons_). This gives him a rating of .480, which is +still higher than in the case of the chimpanzee. Most interesting in +this connection is the fact that the pyramid in the gorilla is .161, +which is considerably less than in the chimpanzee. The pyramid, as +will be recalled, indicates the degree of skill that an animal has in +controlling its voluntary movements; that is, in making its muscles act +in many and varied ways according to the dictates of the will. That the +agile, speedy, and acrobatic chimpanzee should surpass the clumsy and +slow-moving gorilla in this particular might be expected. In almost +every other detail of its development the brain of the gorilla is +nearer to man than is the brain of any other ape, great or small. Those +who have studied this question are fully convinced of the near approach +in brain structure which all three of the great manlike apes make to +the human brain. If any final estimation is justified at the present +time, the gorilla’s brain appears to be the most advanced of all the +apes and is, in fact, almost human. + + + + +CHAPTER XI + +HUMAN AT LAST + +THE BRAIN OF PREHISTORIC MAN + + +Those individual characteristics which distinguish the orang, +chimpanzee, and gorilla may be easily recognized. Yet, notwithstanding +their striking differences, these animals all belong to the same +family, called the _Simiidæ_. As a family this was and still remains +the highest in the ape world. All of the great apes manifest certain +pronounced manlike tendencies. Up to this point they were progressive, +but beyond it they did not go. They were not equipped to reach the +upper footholds or to gain the vast plateaus on the top of the world. +This last achievement remained for another, who, being freed from many +simian restrictions, had already outstripped the anthropoids. + + +_Human Superiority_ + +As a machine, this newcomer in the animal world was more effective than +any of his forerunners. His human superiority was not due to higher +speed, greater strength, or better staying powers. Many of his animal +competitors could far outdistance him, could easily overpower him, +could surpass him in endurance. He did, however, have an exceptional +advantage. He was able to combine these essential qualities with +many others in a variety of ways and thus gain an ultimate supremacy. +In the end it was better brain power that raised man above his lower +contemporaries and set him on his path toward human success. This new +power of his did not come all at once. It needed the steady effort of +ages to reach its present development. Compared with the existence +of other species, the human race is relatively young. In point of +geologic time so also is the human brain. Many students are agreed +that temporally and in other respects our brain has scarcely outgrown +its childhood. The brain power of to-day may require further ages of +development to attain its highest possibilities. + +When man first appeared on earth he had much in common with the +great apes. Although not descended from them, he had inherited with +them many qualities from a common ancestor. It is now settled beyond +question that in earliest times the human brain possessed all of the +basic patterns and mechanisms still to be found in the gorilla, the +chimpanzee, and the orang. It had one fundamental advantage that +greatly improved its capacity for developing its power. Expansion was +the secret of this advantage. It was apparent in all parts of the +superbrain, but most prominent in the department of the highest mental +faculties, the frontal lobe. We may discern this great advance at a +glance by comparing the sloping, narrow foreheads of the great apes +with the high and prominent brow of man. The frontal lobe gradually +pushed forward over the eyes, and in consequence the forehead slowly +rose above them. It seems fair to say that as the brow grew higher +through successive stages the race gradually rose in humanity. We are +still much in the dark concerning the early phases of this slow rise +to power. Some of the stages, it is probable, we shall never know. On +the other hand, a large number of human fossils have been found during +the past century. From these it is possible to decipher what the human +brain must have been like at certain critical periods of man’s long +journey. The brain, like all other soft parts of the body, disappears +in time after death. How is it possible, therefore, to speak about the +brains of men long since dead, or of races long ago extinct? + + +_The Fossil Records of Man_ + +It is true that only the bones of ancient peoples remain to tell us +what they were like. Many of these bones have become fossilized by +impregnation with minerals and are, so to speak, turned into stone. +Thus they make an enduring record of man’s bony framework. From these +petrified bones we can read many things about the people of the past to +whom they belonged. We can measure their height, determine the manner +in which they held their bodies in walking, and estimate their muscular +strength. We may even rebuild their bodies about their skeletons by +using certain standard measurements and so gain a fair idea of what +these men must have looked like when alive. From the shape of the head +it is possible to decide whether the jaw was massive and protruding, +or of modern type; whether the cheek bones were heavy and prominent +or relatively inconspicuous; whether the forehead was low and receding +or high and broad; whether the nose was flattened or had a high nasal +bridge; whether the chin was weakly developed or large and firm; +whether the brain case was small, round, and narrow, or long, high +vaulted, and capacious. + + +_Brain Casts of Extinct Races of Men_ + +Many other characters of extinct races may be determined by means +of exact measurement. So much has already been accomplished in this +way that it is possible to reproduce a reasonable facsimile of races +that vanished long ago. It is possible also to reproduce a reasonable +likeness of their brains. Reproductions of this kind depend upon the +use of the fossil skulls as molds from which plaster of Paris casts +are made. Upon the inner surface of the skull the brain makes certain +definite impressions. It leaves grooves in the bone where great +arteries run. It shows deep indentations caused by the convolutions. It +contains other landmarks indicating the size and position of certain +prominent features in the brain. These casts do not show the brain +characters in all their sharp details because within the skull the +brain is covered by three layers of membranes and surrounded by a thin +jacket of fluid. In consequence, all of the prominent characters, +although easily recognized, are somewhat veiled. It is for this reason +that we are unable to detect every coil and groove in a brain cast +of a fossil skull. We may, however, discern many important features +and thus form an accurate estimate concerning the brain characters +of several prehistoric races of man. Many casts of this kind are now +available for study. + +It is probable that a number of distinct species of prehistoric races +have passed away leaving no trace of themselves. Even the bones of +man’s body gradually crumble into dust unless, by some fortuitous +circumstance, they are slowly converted into stone through the +deposit of mineral salts. It seems likely that only a few of man’s +skeletal remains have been preserved for us in this manner. By far +the vast majority have gone the way of all flesh and most bones. The +few precious relics that we thus far have had the good fortune to +discover are treasured as rare possessions. They tell us in a somewhat +disconnected way of many ancient people who have lived long before our +times. Yet, however disconnected this story may be, however wide its +gaps, however serious its omissions, it would be improper to overlook +the fossil evidence of these early people. The fossilized relics must +be permitted to set forth the story which they have to tell while we +endeavour to keep our interpretations within the bounds imposed upon us +by the nature of the evidence. + + +_Brain of Java Ape Man_ + +The brain cast representing the most ancient race of men yet discovered +is that of the ape man of Java (_Pithecanthropus erectus_). Dr. Eugen +Du Bois, when he made his wonderful discovery in Java, found almost +the entire skull cap of this primitive man, who lived somewhere between +500,000 and 1,000,000 years ago. His brain was remarkably small. It was +not nearly so large as our modern brain or even as the brain of many +other prehistoric people. Its capacity was only 940 cubic centimetres. +This is small for a human brain, which ranges between 1000 to 1400 +cubic centimetres. But if it is small for a man, it is much larger +than any ape brain. An interesting comparison as to the size of the +ape man’s brain is afforded when the brains of a large gorilla, of the +Java ape man, and of a modern man are placed side by side. At once the +differences are apparent. The brain we are now considering clearly +occupies an intermediate position between the gorilla and modern man. + +The striking feature about the brain of the lowly ape man is the +great expansion which has taken place in the department and permanent +headquarters of the highest mental faculties--the frontal lobe. +Compared with the brain of the gorilla, there can be no dispute as to +the great advantages held by the ape man in this part of his brain. The +convolutions are plainly shown in this frontal area. In fact, these +coils are more prominent in this region than elsewhere. This fact does +not imply that the convolutions in the brain are supreme in the frontal +lobe of the ape man. If they seem less prominent in the other lobes +it is only because the frontal coils in all cases make more positive +impressions upon the skull. It is fortunate, though, that these coils +may be so clearly seen in that region of the superbrain which reveals +the development of the highest faculties. We should also bear in +mind that this department of the chief executive in the frontal lobe +is preëminently a human possession. A comparison with the gorilla’s +brain shows at once the great expansion which has occurred in the most +responsible portion of man’s superbrain. In consequence of such frontal +growth the human race distinguished itself in creation by acquiring all +that is implied in the title _Homo sapiens_ (man of wisdom). + +Another decisive feature appears in this frontal region. The left +convolutions are slightly larger than those on the right side. In +all probability this difference in size indicates that a highly +characteristic human quality has already been introduced. In the ape +man the right hand already appears to have become the leader in all the +varied skillful performances of manual achievement. + + +_Speech_ + +In this early period it seems likely that man was using his hands +for constructive purposes. Of far more significance and bearing +more decisively upon the destiny of humanity is the appearance of a +well-marked coil in the lower portion of this frontal lobe on the left +side. In all living races of man this convolution is associated with +the control of spoken language. From this specialization it is apparent +that the ape man had acquired the powers of speech. Even if his frontal +lobe were small, it far surpassed that of any ape however highly +developed. + +It is clear from these facts that the primitive ape man of Java had +risen to a plane far above the gorilla, although he was still much +below that of modern man. Visualized from his brain, this Java man must +have had increased powers of reasoning. He must have been capable of +making better adjustments to life than the gorilla or any of the great +manlike apes. He possessed the ability to build up a greater sphere of +experience and make some approach to human personality. His tendency +to right-handedness was a distinctly human character, around which are +built many of man’s most productive specializations. In all of his +qualities the Java man was much below his later human successors. It is +difficult to estimate how much skill he had acquired with his hands, +but it seems almost certain that he added one supreme advantage to the +motor equipment of animal life. HE HAD LEARNED TO SPEAK--to communicate +in verbal language. The animal machine had acquired a new means of +expressing itself. It was capable of developing a new output in the +production of which it became highly prolific. + +Several theories have been advanced to explain the development of human +speech. One of these attributes the origin of language to gestures, +especially those made with the hands. Gestures indicating direction, +location, distance, size, shape, motion, number, and many other +specifications became associated with vocal expressions. These symbols +were the basis of language, which required special speech centres in +the brain for its control. + +This means of communication laid the foundation of all human knowledge. +Doubtless the linguistic ability of the Javan ape man was extremely +crude, but he had taken a decisive step in a direction necessary to the +further development of mankind. + + +_More Effective Use of the Senses_ + +In the department of his body and contact senses the ape man’s brain +shows marked advances over the apes. The expansions here must be +regarded as particularly connected with the free use of the hands and +arms and the assumption of the erect posture. A much richer supply +of raw materials in the way of sense impressions from the legs and +arms, and from the body, generally speaking, made possible a more +effective turnover and output of nervous energy. During this time man +was learning many new uses for his hands in devising original means for +maintaining and advancing his footholds in life. + +The departments of sight and hearing situated respectively in the +occipital and temporal lobes of the brain show that degree of expansion +which supplied greater human powers. Man could see, and understand +better what he saw. He could hear, and understand more fully what +he heard. He was capable of more effective appreciation of his +surroundings. If he obtained a better idea of the world through his +sense of sight, he put these more ample impressions to better use in +the visual direction of his actions and more especially in guiding the +work of his hands by his eyes. + +If his sense of hearing likewise gave him better understanding of the +audible world about him, it was most important in that it contributed +to the upbuilding of his vocal speech. Sounds which he heard began to +have new meanings to him. From this it was but a step to translate such +sounds into spoken words with fixed meanings of their own. + +In all of these particulars the brain of the ape man had made definite +advances. It was superior to all of its forerunners in the animal +kingdom. The fact that it had thus advanced brings to mind many +perplexing questions. Why had this great change taken place? What +causes had produced the marked extensions in the frontal lobes and in +all other lobes, sufficient at last to lift man up to a human level? +Attempts to answer such questions venture into the field of conjecture. +Many factors yet unknown may have been the real causes in producing +this remarkable change. + + +_The Human Hand and Foot_ + +One great difference between man and the manlike apes seems to be based +upon the character of the feet. Man had at length acquired two feet +upon which to stand upright and make his way. His erect posture had +caused many changes in his body, including the position of the head, +the relation of the eyes, and the length of his limbs. None of these +changes had more telling effect upon human destiny than the final +freeing of the hands for occupations other than locomotion. In this way +man acquired his most useful advantage--the hand. It became his chief +reliance, the basis of his constructive abilities, and the guide of +his analytical powers. It has been the achievement of his hands that +has carried man onward. Some authorities believe that brain development +was the chief factor in human progress. Such no doubt is the case, +but it was the hand that called upon the brain for its progressive +development. + +Whatever other factors were at work, the hand was one of the most +potent influences in the rise of man. With the brain to direct its +action, to expand its usefulness, with the upright posture to give +free range to its executions, with speech to make its accomplishments +available to all, the hand became a master key, opening all the ways +leading through the vast domain of human behaviour. If the influences +which determined human emergence from the lower levels of animal life +might be catalogued as a working theory, they would perhaps appear in +the following order: + +1. The development of the human foot upon which to establish the erect +posture. + +2. The freeing of the hand in consequence of the erect posture for the +purposes of human success. + +3. The expansions of sight and hearing for the better appreciation of +the world and the more effective guidance of action. + +4. The development of speech. + +5. The establishment of human personality and the development of higher +mental faculties. For the successful administration of these special +powers, a brain of at least human capacity was necessary. + + +_Brain of Piltdown Man_ + +When Mr. Dawson found the fossil remains of the Piltdown Dawn man he +brought to light another view of the human prehistoric brain. There +are many indications that the Piltdown men had made great strides in +their brain power. This is especially apparent in the frontal lobe. +The convolutions are prominent, especially that one upon the left side +which plainly indicates the power of speech. These early inhabitants +of England must have been more gifted than the humbler ape man. Such +at least is the evidence of the frontal lobe in which the department +of the highest mental faculties was much better developed. Similar +advances appear in the parietal regions, suggesting that the hands of +these Dawn men had acquired increased capacities as constructive agents +and sensory organs. The large expansion in the department of body and +contact senses plainly signifies great advantages gained in exploring +the world. Piltdown man must have understood the consistency, the +texture, and shape of the things he touched. The weight and mobility +of objects gave him information concerning their use. The advantages +of wood and stone for projectile and penetrating purposes, the utility +of sharp edges, the flexibility and tensile strength of various +tissues, like the bark of trees or climbing vines, all came to him +as revelations evoked by his new powers for sensing his world. These +revelations were of much service in other ways. The Dawn man could +utilize these sense impressions in directing new actions which helped +him to overcome obstacles or to gain greater security. He could now +combine stick and stone in a manner advantageous for his daily contacts +with life. There may be some question whether the earlier ape man of +Java had learned the secret of making implements for himself. With the +Dawn man of Piltdown the case is different. It seems most likely that +he had already established the industry of instrument making. Some +students of this question still hesitate to believe that the dawn flint +implements (eoliths) found in association with the Piltdown remains +were really the product of human hands. It is probable that the Dawn +man already possessed the great advantage of being right-handed. The +chipping of stone implements would make it necessary for him to hold +the flint in one hand and flake it skillfully with the other. The +departments of hearing and sight both show an expansion similar to that +in the other parts of the brain. + +The Piltdown brain is superior to that of the Java ape man in all +particulars. It indicates the power of speech, the development of +right-handedness, and the establishment of higher mental faculties. +It also attests that the Dawn man had come a long distance from that +parting of the ways at which the human race separated from the great +apes. + + +_The Neanderthal Brain_ + +The time assigned to the Dawn man’s day on earth varies considerably +according to different estimates. The latest calculations place this +time at a little over a million years ago. By comparison, Piltdown +men were certainly more ancient than another race which dominated +Europe for long ages. This was the famous Neanderthal race. These early +and long extinct people migrated into Europe from the East. Their +scattered fossil remains found in many different parts tell the same +story of an unusually powerful race. In stature they were relatively +short, probably not averaging much more than five feet three inches +in height. Their arms were long and powerful, their necks thick and +extremely muscular. Their legs were heavy and slightly bent at the +knees. As a race they were distinguished by the shape of their heads +and the size of their brains. The Neanderthal had a low, retreating +forehead and a head that was peculiarly flat near the top. It seems +as if the head were especially constructed as part of an effective +fighting machine. Heavy ridges of bone surmounted the eyes much as is +the case in the gorilla. The head was set down well upon the shoulders. +The jaws were heavy, indicating that the teeth as well as other parts +of the body might be employed in combat. The nose was broad and flat +and the chin lacked prominence. All of these features must have given +the Neanderthal man a brutish appearance. The low beetling brow, the +flattened vault of the skull, the heavy jaw with receding chin, the +broad flat nose, all gave him a countenance not unlike that of the +great apes. Visualized from his fossil remains, the Neanderthal was a +savage-looking creature. He would have been a dangerous wayfarer for +the unwary to meet. He was probably so hideous in his appearance that +his presence gave offense to men of more refined sensibility. This +seems like a harsh judgment upon the Neanderthal. It is a low estimate +of him which his brain does not justify. As a matter of fact, the size +of the Neanderthal brain is somewhat greater than that of any modern +races. If size alone were the standard, such a brain would not indicate +a low degree of mental organization. But size alone is not a reliable +indicator of brain capacity. Unusually large brains are often inferior +in their brain power. It is said that the largest brain, both by weight +and measure, was that of a feeble-minded gardener at one time employed +in a large public garden in London. The volume of the Neanderthal +brain is not a convincing argument as to its efficiency. From other +indications, however, it is certain that this race had made definite +advances in human progress. They were skilled artisans and flint +workers. They had command of fire, which was employed in the upbuilding +of distinct industries. Far from being lowly, ape-like creatures, they +had many of the higher attributes of man. + +The earliest discovery of these ancient people occurred in 1848 when +Lieutenant Flint found the first Neanderthal skull in an old quarry at +Gibraltar. The real meaning of this find, however, was not appreciated +until more than sixty years later. + +One of the most important Neanderthal discoveries was made in the +valley of the Dordogne in southwestern France. In a cavern near the +little village of La Chapelle-aux-Saints, the abbés Bouyssonie and +Bardon (autumn, 1908) found the skeleton of a primitive man. The +body rested upon its back, with its head toward the west, its legs, +thighs, and forearms folded together. The head had been protected by +flat stones, and many skillfully worked flints of the Mousterian period +surrounded the body. There was every evidence of interment and burial +ceremony about the discovery which, it was finally decided, was the +skeleton of a middle-aged man belonging to the Neanderthal race. By +measurement it was found that the skeleton must have contained a brain +of large size, considerably larger than the average modern brain. +The brain cast of this prehistoric man gives us some clear idea of +Neanderthal brain power. In shape the brain is distinctly flat. The +arching in the region of the forehead, so prominent in modern races, is +absent. This part of the brain seems to sink inward as if the frontal +lobe had gone somewhat into eclipse, or had not yet made that decisive +expansion characteristic of later races of man. This condition, +however, corresponds exactly with the low retreating forehead of the +Neanderthal. When compared with the ape man of Java, or with the Dawn +man of Piltdown, the Neanderthal brain does, however, show expansion +in all of its major departments. The parietal, occipital, and temporal +lobes have all increased in size. This is true also of the frontal +lobe, but the ratio of expansion appears to be less here than in other +areas. It is in this department that the real flatness of the brain +is most pronounced. The convolutions in the frontal lobe fail to give +the superbrain those dominant characters which produce a high, wide +forehead in modern man. This apparent failure of the frontal lobe to +attain greater proportions must have had far-reaching influences upon +the life and destiny of these primitive Europeans. + +All of the major departments of the brain show considerable expansion. +The entire brain of the Neanderthal gives evidence of progressive +development at the same time that it manifests many signs of deficiency +and incomplete realization along the higher lines of progress. + + +_Brain of Rhodesian Man_ + +Asia and Europe have produced evidence of prehistoric man. Until quite +recently Africa has been peculiarly silent in this regard. At length +even the Dark Continent has revealed signs showing that man of a +primitive type has gone a long way toward the south in his wanderings +over the earth. This important discovery was made in Rhodesia and first +publicly reported in 1921 by Mr. William L. Harris. The conditions of +this discovery were peculiar and significant. Actual remains of two +human skeletons were found at Broken Hill mine in northern Rhodesia. +Connected with this mine there was originally a natural cave about 120 +feet long. This is known as the bone cave. It contained a vast number +of animal bones all impregnated with the salts of zinc and lead. At the +bottom of this cave the human remains were found. Like all of the other +bones, the human skeletons were incrusted by zinc and lead. The cave +itself seems to have been the ancient feasting place for hyenas, which +dragged thither their prey. There is some suspicion that these human +remains may have come to their last resting place in the cave of bones +in a similar manner. The cleft of the roof of the cave here is far in, +which suggests the possibility that the men or women whose bones were +found may have fallen into the cavern. Certain features of the skull, +however, have convinced eminent authorities that these individuals +belong to a very ancient prehistoric race. The face is far more brutal +than that of any other known human being, living or extinct. The +enormous eyebrow ridges resemble those of the gorilla, the nose is flat +and has that snout-like appearance suggesting a peculiarly significant +mark of the beast, known only in one other extinct member of the human +family, the Neanderthal man. Another remarkable feature of the head is +the great size of the palate and teeth. The brain case and the features +of the brain lend support to the view that this Rhodesian man was even +older and more primitive than Neanderthal man. + +By all the signs of his frontal lobe the Rhodesian must have been a +humble sort of human. Nothing in this department of his brain suggests +any near approach to the attainments of modern man. The frontal lobe +bears many marks of ape-like characters. It indicates at the same +time a brain power which surpassed the limits of the great apes. It +was a brain fast carrying man upward to the broader plains of human +experience. The lot of the Rhodesian must have been precarious. He +was pitted against formidable animals of the African wilds. But, +judged by his frontal lobe, his brain had not left him destitute for +the exigencies of such competition. He doubtless possessed the power +of speech and the capacity for making human combinations. Compared +with lower mammals he had a more facile association of ideas and could +profit more effectively from experience. The evidence of his parietal, +temporal, and occipital lobes indicates definite progress in all +departments of sense perception. His brain was human though still in +the rough. Whatever position is finally assigned to this far-distant +cousin in our human family, he seems from his brain to have been a very +simple sort of human being, older perhaps and even more primitive than +any of the Neanderthal race. + + +_Changes in Human Race Extremely Slow_ + +It is impossible to give the exact dates for the appearance of the +different races of prehistoric men. At best, our ideas concerning their +antiquity must be approximate. Yet these fossils do not leave us in +doubt in one respect at least. We know and we may prove our knowledge +in many different ways that man has inhabited the globe through long +ages, whether we rate these ages as hundreds of thousands or millions +of years. Throughout these ages man has varied considerably. At first +he bore many close resemblances to lower forms of life. Slowly he +improved and manifested a progressive advance toward higher humanity. +We may be inclined to question this progressive change from one stage +to another largely because our own experience of life is limited to +such a short span of time. Within the memory of any man the changes in +his fellows seem inconsiderable. Mankind appears to have a dominating +fixity in appearance. It is only a little more than sixty generations +since the birth of Christ, and during this time the racial characters +of men have changed but little. The white man, the red man, the black +man, and the yellow man, are all much the same in the form of body, the +shape of head, the appearance of face, as they were sixty generations +ago. There is more than a striking figure of speech in the scriptural +definition that a thousand years are but as a day in the endless +expanse of time. Measured by such days as these, man has changed slowly +but surely. When we contemplate long days of this kind, each of a +thousand years, their accumulation in the existence of our race takes +on a new meaning. Estimate, for example, how far back ten days of this +time would take us. We should find ourselves in the life of the world +as it was ten thousand years ago, in that critical period when a vast +social and racial change was altering the colour and complexion of +human existence in Europe. The senile but still wonderful Cromagnon +race was then limping along to the last stage of its declining old +age and was about to disappear. The hardy and practical man of the +New Stone Age had already arrived and was fast becoming master of the +situation. The Cromagnon artist-hunter was passing the sceptre of human +control in Europe over to the hard-headed Neolithic business man. +Another fifty days (each of a thousand years) still further back and +we find again a momentous crisis. At that time the Neanderthal man was +passing. In spite of all his rugged vigour, his day on earth was done. +He had carried on existence successfully for seven or eight hundred +thousand years, but now the time of his extinction was at hand. These +seven or eight hundred thousand years would merely be seven or eight +hundred days, according to the new kind of timepiece by which we are +endeavouring to measure the duration of human progress. + + +_Cromagnons Replace the Neanderthals_ + +We may pause to seek some reason for the momentous change when the +Neanderthal appears to have bowed before the Cromagnon. The real secret +in the failure of the old race and the success of the new may be found +in the brain. It was the increased brain power of the Cromagnon which +produced the supremacy of this great race. It was this power which gave +Europe its first pioneers in art and, for all mankind, opened the doors +of creative imagination and appreciation of beauty in the world. + +It would be particularly illuminating if a brain of the Cromagnon race +were available for study. These first artists occupied an exalted +position. They began their life in Europe about fifty thousand +years ago and carried on their industries for a period twenty times +longer than the duration of the Christian Era. At present there is +no Cromagnon brain cast available. We may, however, draw analogies +from certain of their human contemporaries, who lived in the middle +part of Europe during the Solutrean period. These were days when +Cromagnon art and industry were at their zenith, when the Old Stone +Age had attained its culminating stage and flourished in its fullest +development. The Solutrean contemporaries of the Cromagnons were +themselves a remarkable people. They are known as the “great mammoth +hunters of Prêdmost.” Their fossil remains have been found in Moravia. +Associated with them were the fossilized bones of nearly nine hundred +specimens of mammoths. In addition to these fossils of men and beasts +there were found many highly worked flints, including spear heads and +other stone implements, all having a pattern which belonged to the +Solutrean period. At Prêdmost, where this discovery was made, there +was a collective burial of fourteen human beings, with the remains of +six others. These great mammoth hunters must have been a large and +powerful race. Their prowess as trackers of great game was exceptional. +The character of their brain as revealed by the casts made from their +skulls places them at once on a plane higher than any of the earlier +races of man. In fact, it admits them to membership in the same race +to which we ourselves belong--that is, _Homo sapiens_. These intrepid +hunters, according to their fossil remains, closely resembled their +splendid contemporaries of western Europe, the Cromagnons. Of these +latter there is an ample record in consequence of which they will +always rank among the best representatives of the human species. +Their remarkable artistic contributions denote far more than the +executive mastery of art. They signalize that new spirit which had +been breathed into mankind, that devotion to the beautiful in life +which created an abiding enthusiasm in all of our race for its highest +ideals and loftiest purposes. From the first days of Cromagnon life +these tendencies were dominant. They were a people who delighted in the +lavish use of personal adornment. Coiffure was of particular interest +with the women and a highly developed personal achievement. Both the +men and the women seem to have been fond of using red and yellow ochre, +much as in modern times, to beautify the body. If certain Egyptian +ladies are credited with the invention of the lipstick and of rouge, it +is probable that they found their examples for such artistic practices +in these Cromagnon prototypes. Drawing, painting, and sculpture were +not the only creations of the Cromagnons in the realm of art. It seems +probable that they had invented some form of music. Their sketches of +dances and masks make it seem likely that to vocal expression they had +added certain artificial accessories in the shape of crude musical +instruments. One character in the artistic discrimination of these +artists and sculptors of the Old Stone Age is of unusual interest. It +shows a distinct partiality for portraying women of extreme corpulence. +Many of their statuettes have been discovered which, in spite of their +somewhat unsightly _embonpoint_, are called Venuses. The most famous +of these is the Venus of Willendorf. It was, however, in the carving +of animal forms that Cromagnon art attained its real heights. Many +living and extinct species of birds, mammals, and fish have thus been +immortalized. Back of all this varied artistic creation there must +have been a social organization of high order, for only a rich human +experience could provide the soil for such vivid and real beauty in art. + + +_The Mammoth Hunters of Prêdmost_ + +The brain of the great mammoth hunters of Prêdmost had a volume close +to the standards of modern men. It had lost those marks of inferiority +which stamp the brains of lower races. It had gained that refinement +of structure in the superbrain which proclaims the ascendant qualities +of humanity. The groove of Sylvius and the central groove show the +boundaries and the size of the several lobes of the brain, which +correspond closely to those of modern man. It is in the frontal lobe +that the most remarkable gains are apparent. The convolutions in this +region are prominent and well defined. That flatness so typical of +the Neanderthal brain has disappeared. These Prêdmost and Cromagnon +people were not a race of flatheads, such as were the Neanderthals. +The human forehead had become high and broad. It was no longer +ape-like and receding, but clearly indicated that the human brain had +developed sufficiently in its latest acquired and most highly organized +department to demonstrate that man at length was capable of real +humanity. + +From the Java ape-man up to _Homo sapiens_ of modern times there has +been a slow but gradual increase in all of the important measurements +of the brain. There has been a gain in length, in breadth, and in +height. Much of this gain has taken place in the region of the frontal +lobe, and thus has expressed itself in expansion in the highest +department for developing brain power. The meaning of this pronounced +frontal expansion is evident in the progressive extensions of human +intelligence. + + +_Progress of the Human Family_ + +Judged by its brain power, the human family has clearly been +progressive. In this respect it differs from all other families in +the animal kingdom. In various parts of the world mankind has lagged +behind. Such is the case in the tropics, where the races of men are +still in a primitive stage. This is true also of many islands of the +sea, in the arctic regions, and in other remote and inaccessible places +of the earth. But given its full opportunity the human family has not +failed to go forward. The line of its progress may not be deemed wholly +satisfactory by the higher standards of enlightened criticism. Yet in +bending the forces of nature more and more to his will as well as to +his convenience, man has surely progressed. Where he has stood still, +where perhaps he has even fallen behind, is in the manifest lack of +control over his own nature. His curiosity has led him to inquire into +every phase and aspect of life upon the globe. But in all of these +inquiries he has given far too little thought to himself. Only within +recent years has he become deeply interested in the mechanisms of his +own behaviour. Least of all has he devoted time and thought to the +organ of his chief reliance, to the creator of his successes, to the +dictator of his future. + +Since his earliest beginnings man has grown in humanity as his brain +expanded. Such a conclusion seems irresistible. If we place side by +side the brain casts of the ape man of Java, the Dawn man of Piltdown, +the Rhodesian, the Neanderthal, the Prêdmost, and the modern, we have +before us a demonstration of this progress more effective than words. + +The regions in which the greatest development has occurred are +easily discerned. Marked additions have been made to the department +of sight in the occipital lobe, of hearing in the temporal lobe, +of body and contact sense in the parietal lobe. The mechanisms for +the amplification of sense perception and sense combination have +been manifoldly increased. But it is in the department of the chief +executive of life and experience that the most decisive advance has +occurred. This area of the frontal lobe, so poorly represented in man’s +nearest kin, the great manlike apes, shows exuberant growth, even in +the ape man of Java. Here its features correspond to those of modern +man in nearly every detail. Its only essential inferiority is its +relative smallness. Its special development of convolutions denotes the +acquisition of human speech and human reason. + + +_Progressive Development of the Human Brain_ + +Were we to select any single area in the superbrain as the department +supreme in mental organization, we should not neglect the claims of +the department for vision, for hearing, for body and contact sense. +Although each of these has progressively expanded, we would be much +more strongly inclined to favour that part of the superbrain which +has been active as the superlative sense combiner, which has served +to develop the fullest impressions of human existence, to accumulate +the widest ranges of experience, to direct most broadly the actions +of our behaviour. Traced through all of their intermediate stages +upward, it is these frontal regions which manifest the most conspicuous +development. The process of this long, progressive expansion in the +frontal lobe reaches back to the earliest periods of man’s existence. +It conveys an accurate impression of the manner in which the brain +has responded to the demands made upon it. The human brain may still +be considered to be in its early youth, in spite of the fact that +more than a million years of human striving lie behind it. This +great antiquity, this remarkable flexibility, have been largely +overlooked. By most of us the human brain is regarded as a finished +product. Its long, prehistoric record as we know it to-day does not +support this point of view. On the contrary, it makes it appear far +more probable that the brain of modern man is only some intermediate +stage in the ultimate development of the master organ of life. The +greatest possibilities for future progress lie in further expansion +of the frontal lobe. For this reason the brain of prehistoric man is +not merely an antiquarian relic, it is a sign from the long ages of +the past showing the road man has followed in his upward course. It +likewise conveys some suggestions concerning the future. For, if the +human brain began as a simple organ and gradually developed through +successive stages, there is reason to believe, if not to predict, that +it may develop still further. + + + + +CHAPTER XII + +IMPLEMENTS OF HUMAN SUCCESS + +HOW THE HAND, FOOT, AND BRAIN LED THE WAY TO HUMANITY + + +It is not sufficient to know that the brain began as a simple organ +and gradually became more complex. Sooner or later we must learn the +reasons why it made this progress. At present we are able to identify +some of the essential principles underlying brain development, yet with +few exceptions the exact causes are still obscure. We may feel certain, +however, that the progressive advances were due to the accumulation +of slight changes which, modifying brain structure ever so little, +ultimately made it more highly effective. Such changes in the different +parts of the body are the result of a complex interplay of influences +acting upon the animal as a whole. The brain has been particularly +responsive to this interplay. It has at the same time been thoroughly +conservative. Throughout all its wide range of variation it has +maintained its basic designs. If readjustment of the body to certain +conditions has resulted in the depreciation of a special part, such as +the eye, the structure of the brain shows corresponding depreciations. +The principle of compensation has also been at work. The power which +may be depreciated or lost in one department is, to some degree at +least, compensated for by others. An illustration of this compensatory +power is afforded by the mole. This animal lives a burrowing life +beneath the ground. Light rays do not reach it, and it therefore has no +need for vision. In consequence, its eyes do not develop the function +of sight. Its senses of touch and hearing, however, are greatly +amplified, and the structure of its brain gives evidence of this +compensatory readjustment. + +Signs of the close relation between the brain and the parts which it +controls may be found in many organs of the body. In some instances +these signs are outspoken; in others they are less clear. It is much +easier to find evidence of this correlation in those parts which play +a conspicuous rôle in life. The arms and legs, the eyes and ears, are +particularly good examples. Modifications which have affected these +parts are distinctly reflected in the brain. If more brain power is +required for their better operation, more ample provision is made for +them in brain structure. + + +_Relation of One Part of Body to Another_ + +It is a debated question whether the brain or the external part of the +body takes the lead in progressive modifications. Some authorities +believe that all advances of this kind are dictated by development in +the brain. Others ascribe the determining influence to the external +part. For the present it seems wiser to consider these modifications as +simultaneous, as affecting the external part and the brain together. +Certain dangers arise from regarding the body as divided too strictly +into definite parts. Such a division has advantages for purposes +of description, but it may tend to obscure the important fact that +life is carried on by the body acting as a whole. In this light the +division between external part and the portion of the brain controlling +it establishes an artificial distinction. Viewed in the light of +purposeful life, one is of little use without the other. Both external +part and the portion of the brain controlling it establish a special +unit which, coöperating with all other special units, carry on the +process of living. + +This view is known as the organismal conception of life. It estimates +the entire animal not as a collection of different parts but as a +combination which makes life possible. According to this conception the +external structure (arm, leg, eye, ear, etc.) and the portion of the +brain controlling it form an operating part of the whole. Modifications +in the one are reflected in the other. They cause mutual reactions. +When eyes are developed for different kinds of vision, corresponding +provisions are made for them in the brain. When legs are specialized +for various kinds of locomotion, brain structure adapts itself +accordingly. + +It is important to realize what the eyes and the ears and the organ of +smell have contributed to the progressive advance of the brain. In all +of these organs there is a marked constancy and sameness among animals +possessing them. Structures presenting a greater variety of form might +have even greater pertinence. It therefore is a more leading question +to ask what relation the brain bears to the extremities, to the fore +and hind legs, to the hands and feet. + + +_History of the Hand and Foot_ + +There is a long history of progressive change back of the hand and +foot. In their development they emerged from more simple structures +connected with the ends of the limbs in certain four-legged animals. +Because they are attached to the limbs in this way, they have played +an important rôle in one of the chief activities of life--locomotion. +The fore and hind legs act as a series of levers. They are moved by +muscles and in this way make transportation possible. Consequently the +modifications in the ends of the limbs in response to special types of +locomotion have a most important bearing upon the life of the animal +and thus upon the brain. + +In animals living upon land such parts of the limbs as touch the +ground are modified by many factors; thus the weight of the body, the +speed of movement, and the kind of locomotion would all exert their +modifying influence. Limbs of several different designs have thus been +produced. Heavy animals, like horses and cattle, which require speed +and endurance for long journeys, need hoofs. Still larger hoofs were +developed by heavier animals, like the elephant and rhinoceros. The paw +was the design utilized by animals like cats and dogs. Their bodies +were not so heavy as those of horses and cattle. They were capable of +great speed and needed sharp nails on their paws to hold the ground +in running and springing. These talon-like nails they also used for +defending themselves or in capturing their prey, as do the lion, +tiger, leopard, and bear. The paw is a more flexible implement than +the hoof. It provides a soft, elastic pad by means of which the animal +touches the ground. In animals like the seal, walrus, and sea lion the +flipper is the design utilized. Here the digits are connected by means +of a web. The wing is the specialization in such animals as the bat +whose transportation depends upon flight through the air. + + +_Locomotor Devices_ + +These various devices for moving the body about on the land, in the +water, or through the air have been developed by mammals. By such +contrivances they are enabled to subsist, each according to its own +mode of living. Some of them have returned to a life in the water. +The result of aquatic habits in mammals is extremely interesting. The +flippers of seals, walruses, and sea lions equip these animals to +swim with great ease and speed. They enable them to clamber about on +the rocky coast by the edge of the sea, or upon the ice fields of the +arctic regions. Because of its apparent limitations, such a life held +little prospect for developing the powers of higher intelligence. A +flipper is in no sense an efficient implement by means of which to +acquire a superior position in the world. The seals and all of their +kind, therefore, offer little promise of progress. They are capable +of astonishing proficiency in the control of their neck muscles and +movements of their heads, but this at best is a meagre advantage. They +are somewhat better off than another group of mammals which took to +the water, namely; porpoises and whales. Nothing in the equipment of +these animals could serve as efficient instruments by which to gain a +preëminent place in nature. + +By developing wings in connection with their limbs the bats were also +excluded from the lines of higher progress. However effective they are +in flight, their wings could not be made to serve constructive purposes. + +Animals with hoofs, such as horses and cattle, elephants and +rhinoceroses, acquired solid and reliable feet for withstanding the +heavy strain which their speed and weight imposed upon them. Hoofs, +however, are far from ideal as universal instruments. Although +sufficient for the work they have to do, they cannot be utilized for +purposes other than those of transportation except, in a certain minor +way, for offensive and defensive tactics. In these animals all of the +digits are either bound together in one large supporting pad, as in the +elephant, or are encased by a horny covering, as in cattle and deer. +In the modern horse but one digit persists, and this is surrounded +by a heavy, horny hoof. Such an implement would not require a highly +specialized endowment of brain power for its control. + +The daily programme of these animals, limited largely to +transportation, calls for no constructive ability and no intentionally +destructive one. The hoofed animals possess no means for accumulating +or storing food in preparation against a day of need. They are forced +to move from place to place in order to find their browsing and +grazing lands. They cannot stand against great changes of climate or +season. They must flee before the advance of winter as well as from +their enemies. The hoof for this reason offered little promise for the +development of a more efficient kind of instrument. Such hoofed animals +as also possess a trunk developed an accessory organ of much value. +It is doubtless an important factor in the high specialization of the +elephant’s brain. Even this flexible instrument, however, has its +decided limitations. + +All of these mammals, whether hoofed, flippered, or winged, have +failed to develop a brain of superior qualities. In no instance is it +an organ capable of a high degree of learning or intricate control of +life. The hoof of the horse, cattle, deer, elephant, rhinoceros, and +the like set the stamp of the wild upon these animals. This is the +keynote of their behaviour. Flipper and wing are equally indicative of +inferior qualifications in so far as efficiency and brain power are +concerned. There may be sufficient reasons for placing these mammals in +the same bracket with man in the great classes of the animal kingdom. +Their inferiorities are apparent, however, when their intelligence is +estimated by human standards. It is then clear how far below the human +level of brain power they are. + + +_The Paw in Relation to Hand and Foot_ + +In our search for animals capable of a greater range of adjustments +we will find another group with a much more promising locomotor +equipment. This group comprises those mammals possessing paws, such +as dogs, cats, bears, rats, squirrels, and the like. In itself the +paw is a most flexible implement susceptible to many modifications. +It possesses five distinct finger-like processes or digits, each of +which is capable of some degree of individual movement. The digits may +be spread out or drawn together; they may be folded or extended. In +every typical paw there are eighteen movable joints, each of which is +capable of some independent motion. Twenty-five muscles make more than +seventy separate movements possible. These figures afford some idea of +what a complex structure the paw is. Attached to the extremity of each +digit is a sharp claw-like nail, beneath which an enlargement in the +skin forms a prominent “tip pad.” Over each of these pads the skin is +arranged in ridges. The ridges roughen the surface and produce what is +called “friction skin.” The roughened skin and the claws at the end of +the digits give the animal better ground-gripping powers. In addition +to the tip pad, each typical paw has four enlargements where the +digits come together. These are the “palm” and “sole” pads. They are +likewise covered with ridged friction skin. The paw terminates in the +wrist or ankle, and at this junction there are two enlargements called +respectively the “wrist” and “ankle” pads. They are also covered with +friction skin. + +This design of paw with its separate digits, its claw-like nails, and +its eleven pads affords an especially adaptable structure from which +to create many different kinds of useful implements. In the gnawing +animals, like the rats and squirrels, the paw is developed particularly +for running and climbing. The long sharp claws serve the purpose of +spurs which, as in the case of the squirrel, may be driven into the +bark of trees. All of the pads in the paw come in contact with the +surface over which the animal is moving, thus giving information +concerning its support and aiding its transportation. + +In moles and burrowing animals the hind paw retains its usual features, +while the fore paw is converted into something resembling a shovel. +The paw becomes broad and flat, particularly in the moles, and there +is no suggestion of any of its pads. Since this specialization is +adapted principally for digging underground, little could be expected +in the way of high attainment for animals of this kind. Their burrowing +capacity is excellent, but this is the extent of their ability. + + +_Special Uses of the Paw_ + +In the meat-eating animals, like the dog and the cat, the individual +digits and the claws are somewhat shorter, but their most important +modification is the fusion of the paw pads and the reduction in the +first digit. This change is a specialization for their more springy +type of locomotion. Such animals run on the tips of the digits, using +especially the second, third, and fourth digits. The paw pads usually +fuse to form one or two which serve to increase the spring of the +animal. The fore limb of the rat may be accepted as the working model, +because it has all of the general features that make up a typical +paw. It provides for running, climbing, clinging, and clawing. When +compared with the paw of a mole, the modifications necessary for a good +digging implement are clearly seen. The pads are no longer needed and +might, as a matter of fact, be in the way. The digits are shorter and +the whole hand is broader and more scoop-like. The paw of the mole is +modified for the work it has to do and has lost many of the structures +necessary for ordinary locomotion over the ground. Long claws are no +longer essential for climbing or clinging, and the nails have been +converted into burrowing ground-breakers. The rabbit and the guinea +pig show changes in the fore paw necessary for rapid transportation +in a kind of jumping locomotion. They have lost the specializations +in the paw necessary for climbing. The nails and the digits are less +long and somewhat heavier. The squirrel, on the other hand, has a fore +paw specialized for climbing trees. This modification has emphasized +the length of the individual digit and particularly the length and +sharpness of the claws. Often the squirrel may be seen sitting upon its +haunches holding between its fore paws a nut, the shell of which it is +attempting to crack with its teeth. Such grasping power is not found +in the paws of animals specialized for running and jumping solely. The +squirrel’s modification of the front paw is extremely important. It +reveals how the animal’s life in the tree has lengthened the digits as +well as the nails. Some degree of power for grasping small objects has +come through this lengthening. The fore paw of a cat compared with +that of a dog illustrates other important specializations. Both of +these animals are strong runners. In running they travel along on the +tips of the digits. For this reason the tip pads and the friction skin +over them have become highly developed for ground-gripping purposes. +The paw pads and the wrist pads have tended to fuse in order to give an +elastic surface necessary for that springy gait determined by running +on the tips of the digits. The individual digits are somewhat longer in +the cat than in the dog. The claw-like nail of all the cat family is +one of their distinguishing features. By means of these claws they are +able to climb trees, which is a provision of great service in procuring +food. Dogs, on the other hand, have short digits, with thick, heavy +nails suited more as spikes in running but not adapted to climbing. +In many of the great cats, like the leopard, climbing trees is an +essential part of their hunting strategy. For this reason they require +long, sharp claws, which may also be used as weapons in attacking their +prey. The long claws of the bear likewise indicate a modification of +the fore paw in adjustment to the animal’s climbing propensities. The +great weight of the bear makes it necessary for it to have these long +spur-like claws in order to get a proper grip on the bark of a tree +when climbing. + + +_Transformation from Paw to Hand_ + +Illustrations of this kind might be multiplied to show that in all +animals having paws these implements have been modified in one way +or another to suit the kind of work they have to do. In the main, +this work is transportation. But there are many special problems in +the different kinds of transportation. There are also numerous other +adjustments to life that are capable of producing profound modification +in the paws. From such facts as these it must be clear that the paw has +been serviceable as the basis for developing instruments suited to many +special purposes. One prominent feature in the several modifications of +the fore paw is the effect which climbing has had upon the length of +the digits and upon the length of the claw-like nails. In the rat and +particularly in the squirrel these effects of climbing are especially +distinct. When climbing at length became a dominant factor in the life +and livelihood of the animal, certain still more decisive modifications +were produced in the paws. We may now endeavour to gain some idea +of that important transformation which occurred when certain groups +of animals took up more or less permanent life in the trees. These +mammals were representative of the monkey kind. They did not resort +to tree climbing as many others have done as an expedient in hunting +or in escaping from their enemies. The trees became their abodes. +Many changes were induced by this new adjustment to life, changes +which affected the muscles and bones and even the skin. During the +process of this adjustment certain ridges upon the skin in the palm of +the hand and sole of the foot began to show marked changes, probably +because they were in such immediate and constant contact with the +branches of the trees. In their basic designs these ridges which form +the friction skin may be traced back to the simplest of pawed animals. +Their successive modifications offer one of the most certain guides in +following the stages through which the hand emerged from the paw. + +Each ridge upon the skin of the paw (_chiridium_) is an elevation +of the superficial layer which contains, at regular intervals, the +mouths of minute canals coming from sweat glands. In its simplest form +each sweat gland in regions of the skin not covered by hair (sole of +the foot and palm of the hand) consists of a mound-like elevation in +the centre of which is the mouth of a sweat duct. With the higher +development of the skin, numbers of these little mounds ran together in +rows thus forming the friction ridges. Depending upon the pressure and +the kind of contact made with the ground or other surface, the ridges +of the skin are arranged either in concentric circles, in ellipses, or +in parallel lines. They serve two useful purposes: First, they roughen +the surface so that it can grip the ground more effectively; second, by +the continuous secretion of fluid from the sweat glands, they keep the +skin soft, pliable, and sensitive. In this last particular, namely, the +sensitiveness of the skin, the ridges also serve in another capacity. +They provide proper locations for nerve endings, necessary to the sense +of touch in all of its various modifications. Thus the paws in the +more minute architecture of their skin pads and friction ridges afford +highly pliable and sensitive instruments by means of which different +kinds of mammals are able to adjust themselves in a great variety of +ways. + +After many intermediate stages of transition the fore paw assumed +the appearance of a hand. Simultaneous with this change the hind paw +also began to manifest many hand-like characters. Potent factors were +at work determining this important transformation. Their influences +were decisive not alone because they changed the paw into a hand but +because they instituted equally profound changes in the structure of +the brain. Such modifications as these brought about many adjustments +to life destined to be the special determinants of human behaviour. One +of the first changes to occur in transforming a front paw into a hand +was the direct result of arboreal life. This modification consisted +of a decisive lengthening of the digits, particularly the second, +third, fourth, and fifth digits. In this way the fingers were formed. +The first digit which ultimately became the thumb did not lengthen to +the same degree as the other four. The chief influence in producing +this lengthening to form fingers arose from the need of a firm grasp +upon the branches. Its effects appear in the simplest monkeys, such +as tarsius. The small hand of this animal has four long fingers and +a diminutive thumb, all of which are well adapted to encircling and +grasping a cylindrical branch. Another important transitional feature +is the flattening in the ball of each digit. In tarsius each finger tip +has a disk-like appearance. This is an extreme development. It produces +what in effect is a suction pad on the tip of the finger not unlike +that observed in some of the frogs (_Hyladæ_). Such suction pads enable +the animal to strengthen its grasp upon the bark. The flattening of the +finger tips due to the pressure required in grasping the limb of a tree +produced a third great change. It caused a corresponding flattening of +the back of the finger tip and thus developed a broad, flat finger nail +to replace the sharp, claw-like nail of the cat, rat, and other similar +mammals. + + +_The Hand of Tarsius and Lemur_ + +The three changes observed in the most primitive of the monkey kind +(_Tarsius_) comprise the pronounced lengthening of the fingers, the +flattening of the finger tips, and the flattening of the finger +nails. These transformations are easily understood in connection with +the necessity of grasping cylindrical branches. In other words, a +prehensile hand came into existence as a result of living in the trees, +and a new kind of instrument made its appearance in relation with the +upper extremity. The need of a firm grasp on the branches was the +fundamental cause of this modification of the paw. It had far-reaching +effects because it created the facility to grasp many other objects and +thus struck the keynote of those further developments which ultimately +gave rise to the grasping hand of man. + +All of the pads covered by friction skin which are characteristic +of lower mammals like the rat and the squirrel may be identified in +tarsius. The tip pads are somewhat changed to form the suction disks. +The palm pads, four in number, occupy their usual position in the angle +between the digits. The wrist pads, two in number, are well developed. +By means of these elastic cushions the animal makes its contacts with +the branches. + +Transition from paw to hand is still more pronounced in the lemurs. +These animals in many ways stand lower in the scale than tarsius. In +them the lengthening of the digits to form real fingers, the marked +development of the thumb, the appearance of friction pads, and broad, +flat finger nails are all prominent. The index finger shows certain +variations in its development. In other respects these lowly members of +the monkey kind manifest definite progress in the change from paw to +hand. + + +_The Interesting Case of the Marmoset_ + +At this point it is interesting to consider the case of the marmosets. +Here the progress which the paw had made toward a more effective +structural instrument encountered a serious setback. The hand of +these little animals, in a general way, has much that resembles a +paw. Although it has long fingers and a prominent thumb, there is +an evident slipping backward. The claw-like finger nails suggest an +actual retrogression in the process of developing a hand. If the +marmosets were actual backsliders, other monkeys of the New World were +particularly progressive. They developed hands which are extremely +human in appearance. Their long, tapering fingers have broad, flat +nails. Their thumbs are fairly well formed. Their finger and palm +pads have characteristic appearances. This interesting group of South +American monkeys show in a most striking manner those changes which +life in the trees has brought about in the fore paw. Such modifications +are especially significant because of their influence upon the +behaviour of those animals which have taken up a permanent arboreal +life. They have also made a deep impression upon the structure of the +brain. The transition from a running, ground-living animal to the +simpler arboreal forms is foreshadowed in the lemur’s hand. In many +respects this transition stands just upon the border line. Its apparent +indecisiveness is recorded in the brain, for the lemur retains many of +the ancient brain features created by older ground-living habits. At +the same time, it indicates certain adventurous attempts to break away +from the earth and ascend into the trees. The grooves of the brain show +this new departure particularly well. They retain their strong family +resemblances inherited through long ages of four-legged ancestors. But +added to this they manifest a tendency to assume the characters which +in due course would lift their successors farther from the ground and +into a more erect posture. + + +_Appearance of the Hand-like Foot_ + +Up to this point attention has been centred upon the important changes +which attended the transition from paw to hand. Equally momentous +were the modifications in the hind paws which resulted in hand-like +feet. This transformation slowly altered the digits, the claw-like +nails, and the friction pads. It modified all of these parts in such +a way as to produce better limb-gripping instruments. A great change +in transportation had taken place. Running over the ground in easy, +secure fashion now gave place to the more hazardous method of climbing +among the branches of trees. A dependable grip was the prime need. +This capacity required long toes with which to encircle the branches, +a powerful sole, and a great toe with strong grasping power. The +four-legged animals that travel over the ground on various kinds of +paws support the weight of the body on two main arches of the foot. One +arch consists of an elastic span between the tip and the sole pads. The +other arch extends between the sole and ankle pads. Generally speaking, +those animals living on the ground first strike the surface at each +step on the tip pads of the four outer toes. As the full weight of +the body is accepted by the hind paw, the sole pads touch the ground. +Last and most lightly, the ankle pads in the region of the heels rest +on the supporting surface. In many running animals of this kind the +heel touches the ground infrequently. Their running and walking in +consequence have a springy quality that prepares them for a quick +bounding start at an instant’s notice. + + +_Strong Grasping Powers_ + +Animals like the rabbit and kangaroo possess hind legs that work +together, while the fore limbs are put forward first one and then the +other. The most effective type of transportation in animals possessing +paws has developed a gait in which the action of the hind leg of one +side follows the action of the fore leg of the opposite side. This +is the manner in which the dog runs. It is also true of all members +belonging to the great cat family. The hind paw is put down in the +footprint of the opposite fore paw. Apparently there is no deliberate +supervision of this action which seems to be wholly automatic in its +nature. To a great extent, however, this automatic regularity in the +hind legs ceased when the four-handed animals came into existence and +began to live in the trees. The problem then was a totally different +one. It was not necessary for these animals to be on their toes every +moment. They did not require the powerful spring formed by the two +arches in the sole of the foot. Their chief necessity was a foot that +would have the grasping powers of a strong hand. In this way they could +make sure of seizing the branches securely. + +The first digit of the foot, which in most pawed animals often fails +to develop, became of greatest service to the monkeys. In most of them +the great toe offers an added means for securing a firm grasp. It may +be extended behind the branch while the other toes encircle it and all +working together produce a firm grip not unlike a wrench on a pipe. +The need of a long lever extending from the tip of the toes back to +the heel, essential to the springy gait of the ordinary pawed animal, +is not so strongly felt in arboreal life. In fact, a foot which is too +long may be an actual disadvantage, while one facilitating the best +kind of gripping power would necessarily require a shortening from toe +to heel. This was the change which took place in the early beginning of +tree life. + + +_Under Direction of the Eye_ + +It is difficult to appreciate all of the decisive modifications +throughout the body which the development of such hand-like structures +determined. Their influences operated in profound and subtle ways. They +caused a great change in body posture. The animal was now able to reach +for branches above its head. This was a long step in the direction of +standing upright. It modified the relation of the head which in most +four-legged animals is directed so that both the eyes and the nose +are turned toward the ground. Reaching upward to grasp branches and +drawing the body in this direction lifted the head. It has been shown +that this action of pushing the head backward and stretching the neck +causes the hind legs to straighten out automatically in exactly the +position necessary for standing erect. Such a beginning of the upright +posture also produced a change in the position of the internal organs +of the body as well as in the position of the eyes. These modifications +influenced the growth of the superbrain, which finally acquired that +appearance seen only in animals possessing hands. Coincident with these +modifying factors, still another important change was in process. In +all four-legged animals the paws, and more especially the hind paws, +operate out of sight of the eyes. The animal does not see their action. +The eye does not watch and supervise the movements of the paws step +by step, but allows them to shift more or less for themselves. With +the appearance of hands connected both with the fore and hind limbs, +this state of affairs ceased. Both the hand and the foot now came under +the critical supervision of the eye. The eye was able to hold in plain +view the performances of the hands and hand-like feet. It could see +and direct their movements. It could single them out individually or +watch them while they all worked together. It could even make critical +discriminations in each hand and in each foot. It could select a thumb +or a great toe, or each one of the other fingers and toes, and thus +guide its movements. This selective discrimination in the hands and +feet was an advantage never enjoyed by any of the pawed animals whose +habit it is to use all of the digits together. In this manner both hand +and foot profited by their new adjustments. As instruments they were +capable of a far wider range of application, although it was not alone +by this expansion in their utility that they became more effective. +They were better agents for sensing the world and possessed a more +ample sensory capacity which arose from their own multiplied movements. + + +_Threshold of a Great Change_ + +In the animal kingdom it would be difficult to find more provocative +influences than those which determined the transformation of paws into +four hands. Considered casually, the appearance of the quadrumanous +monkeys in all their varieties seems little more than the addition +of many interesting forms of life. This addition, however, had a far +greater significance. The four-handed stage of animal existence led to +the highest development of the brain. Without this stage the ultimate +advances in life, the supreme achievements in progress, would have been +impossible. Numerous factors contributed to the acquisition of hands +and hand-like feet, but no one of them was more potent in the final +outcome than the effects of tree-living. Almost every other combination +of habitat and adjustment had exerted its influence upon the form of +the mammalian body, yet in no other instance has there been achieved +a success comparable to the development of hands. Most mammals are +equipped with highly efficient eyes, keen ears, and a serviceable +sense of smell. These endowments have had opportunity to contribute to +the efficiency of life. But neither sight nor hearing nor smell was +sufficient of itself to determine those advantages capable of giving +the animal a supreme position. It was the hand which opened the door +to give the senses those opportunities never enjoyed before. It called +upon the brain for further expansions to direct new ranges of movement. +It required additional brain extensions for a greatly amplified sense +of touch in the fingers and palms, in the toes and soles of the feet. +It was the hand, in a word, that afforded an entirely new grasp upon +life and in the end created not only a new order of mammals but +almost a new kingdom of life. The transition from paws to the hands +of the quadrumana is the threshold of an epochal change. As the paw +was the basic pattern for the hand, the hand was the indispensable +stepping-stone to the development of man. This formula may perhaps seem +altogether too simple and graphic. It would be such, in fact, if many +of the important intermediate stages in the process of development were +overlooked. These stages may now be considered. + +The consequences of the transition produced under the influence of +tree-living appear conspicuously in the lengthening of the digits +to form fingers, in the appearance of an opposable thumb, in the +acquisition of a grasping hand. All of these are definitely adaptive +changes. They are applied directly to meet the conditions of locomotion +through the trees. But if these modifications conferred upon the +animals many real advantages, they also introduced certain imposing +hazards to further progress. They were adequate for the mastery of +arboreal life, yet at the same time they permitted the forest to become +master of these four-handed animals. This is true in exactly the same +way that the sea imposes its laws upon aquatic mammals, the plains +dictate to the ungulates, and the air exerts its control over the bats. + + +_Possession of too Many Hands_ + +So far as the monkeys are concerned, an obstacle lies squarely across +the path of further progress. They are possessed of too many hands. +Hand and hand-like foot both serve the purposes of locomotion. Neither +the one nor the other is afforded those opportunities of exclusive use +which are essential to the highest development. This is true even +of most of the monkeys of the Old World, like the macaques. Their +locomotion requires the use of all four extremities. They run along +on the top of the branches, grasping firmly as they go. They leap +from one branch to another, employing all four hands in this mode of +transportation. As a result of these activities the hands are long +and slender, the fingers long and tapering, and the thumb short but +opposable. The foot has much the appearance of the hand. + +One group of the ape world offers a striking departure from this +more general rule of development. This exception is particularly +interesting. It appears in the baboon and more especially those members +of their family which have taken up a life upon the ground. With the +baboons the resumption of terrestrial life came long before any of +the monkeys had made pronounced advances toward the erect posture. It +is for this reason that when these animals adopted habits of ground +life they readjusted themselves after the fashion of other four-legged +animals. They travel about much like the dog or cat, with their muzzles +directed to the earth. In fact, many of their features, both in head +and body, take on a definite canine appearance. A feature of special +significance is the manner in which their fore and hind limbs have +reacted to the influences of ground-living. The great lengthening in +the hands, fingers, feet, and toes, conspicuous in monkeys that live +in the trees, has actually been reversed in the baboon. It is still +proper to speak of hands and feet, but both hand and foot have shown +striking tendency to revert to paws. This specialization illustrates +a remarkable disgression in the development of the monkey kind. It +means, if it means anything at all, that the adaptations necessary +for carrying on life in the trees have withdrawn their influence +and permitted the habits of adjustment to the ground to modify the +character of the extremities. In four particulars the hand of the +baboon shows distinct tendencies to revert to a paw: + +1. All of the fingers are shortened. + +2. The thumb has been reduced if not to the state of a vestigial +tubercle as in the dog, at least until it has become extremely +rudimentary. + +3. The nails have become much longer and more slender, as if they were +tending to form claws. + +4. Both the tip pads and the palm pads have become more prominent, the +latter actually fusing to form a single palmar cushion. + +In the foot similar tendencies toward a paw are present. The lesser +toes and the great toe are much shortened, and there is a distinct +fusion of the plantar pads. This reversion in the hands and feet of the +baboon shows clearly how readjustment occurred when the influences of +tree living were withdrawn. It also demonstrates the strong tendency +for the chirideal structures to assume the ancient patterns of the +paw in response to the habits of four-footed living upon the ground. +The baboons, therefore, cannot be considered in the direct line of +progress. They not only failed to advance the cause of developing +the hand but they did nothing to further the erect posture or the +progressive expansion of the brain. It was perhaps the large size of +their body that made it necessary for them to desert the tree and +seek more secure support upon the ground. This increase of body size, +however, came at an early period, long before the primates had begun to +feel those decisive influences which favoured standing erect. + + +_Brachiation and the Erect Posture_ + +Considerably later in geologic times another class of apes made its +appearance, which felt the full power of this determining influence. +These animals were the gibbons. They introduced a new type of +transportation. Their locomotion no longer depended upon running along +on the tops of the branches, or leaping from one support to the next. +They introduced the novel method of swinging by the hands. Reaching +for a branch over the head with the right hand, the gibbon swings +its body forward to grasp the next branch in advance with the left +hand. Swinging in this manner, step by step, first with the right +hand, then with the left, these animals walk through the trees. The +results of this arm-swinging locomotion (brachiation) are apparent +in the development of the hand. The fingers, tip pads, the palm, and +the palm pads are greatly elongated. Similar lengthening is also +apparent in the forearm. The acrobatic manœuvring requisite to such +locomotion has developed a high degree of skill in using the hands +and arms. It also requires a close coöperation between the movements +of the upper extremities, eyes, and head. The influence of these +several modifications has impressed itself upon the brain. But the most +decisive effect of the gibbon mode of locomotion is seen in the posture +of the body. The swinging by the hands well above the head produces an +almost constant erect posture. The muzzle no longer points, as in the +great majority of monkeys, toward the ground. It, as well as the eyes, +is now directed toward the horizon, and thus those factors which have +contributed most to an upstanding, forward-looking primate were first +introduced by the gibbon. The foot of these animals, while it retains +many features and markings of a hand, affords a fairly satisfactory +support for bipedal locomotion in the erect posture. Obviously the +effects of tree life are responsible for these changes in the gibbon. +All other monkeys up to this stage have been embarrassed by an +over-endowment of hands. But the gibbon, by over-emphasizing the upper +extremity, has to some degree nullified the importance of hand-like +feet. It has begun the solution of that perplexing problem which was +imposed upon the monkeys by their almost exclusive tree life and which +must be solved in order to provide for the manlike specializations +essential to bipedal locomotion. + +In this gibbon level of the ape world such specializations began to +manifest themselves. From some gibbon-like progenitor, early in the +Age of Mammals, there arose a common stock capable of producing all of +the modern gibbons, the great anthropoid apes, and man himself. This +gibbon stage of development contained the potential material from which +to evolve the erect posture, bipedal locomotion, hands freed for the +purposes of the greatest utility, and a brain adequate to the needs of +the highest primates. + + +_A New Grasp on Life_ + +In the three great anthropoids, orang-outang, chimpanzee, and gorilla, +the hand is approaching more closely to the human pattern. In all three +the leading advance is due to the development of a more effective +opposable thumb. The result of this change has caused the disappearance +of the two wrist pads so characteristic of the mammalian paw and so +prominent in the great majority of monkeys. Power to oppose the thumb +against each one of the fingers separately has increased to a great +extent. The opponens muscle of the thumb has become more prominent +and caused the appearance of a conspicuous muscular swelling in the +palm of the hand, the thenar eminence. The palm muscles developed +in connection with the little finger have likewise occasioned the +appearance of the hypothenar eminence and at the same time the +disappearance of the second wrist pad. These developments, all clearly +seen in the anthropoid apes, and most prominent in the gorilla, reach +their greatest proportions in man. They are evidence not of the further +adaptation of the hand to locomotion but of its liberation for other +and more constructive purposes. + +The effects of this advance in the hand from one primarily intended +to provide a firm grip upon the limbs of trees to one of almost +universal application are revealed by alterations in the palmar lines. +These lines are three in number, namely, the anterior, middle, and +posterior groove. In the gibbon they extend across the palm almost +parallel to each other. They are creases which represent the lines of +palmar flexion resulting from grasping cylindrical branches. In the +orang-outang these lines are still essentially parallel, indicating a +hand designed to grasp a cylinder. In the chimpanzee and gorilla the +palmar grooves begin to converge toward the space between the index +finger and thumb. In man this convergence is complete, due to the +development of the powerful hand muscle which permits the opposable +thumb to reach the other fingers. This progressive convergence of the +palmar lines indicates the development of a hand no longer intended +for the simple purpose of grasping a cylinder, but not constructed +to take firm hold upon a sphere. Figuratively this change in hand +from cylinder- to sphere-holding capacity is illustrative of actual +development in the intellectual grasping powers that became the +distinguishing feature of mankind. + + +_A Firm Foundation for Humanity_ + +Thus far we have been able to trace the stages by which the hand +developed in consequence of tree life. It is now necessary to follow +the modifications which terminated this arboreal domination and +consequently liberated the animal from the forest. This transition +determined an adjustment to life that was finally productive of the +most effective behaviour. The outcome of this modification was the +freeing of the hand for purposes other than locomotion. The immediate +agent that made such a result possible was the development of a foot +capable of supporting the upright posture. This foot, as it made its +appearance in man, passed through a long series of transitional phases. +It had its beginning in a definitely prehensile stage when in the +earliest of the monkey kind it was hand-like in its appearance. The +structure that was the forerunner of the human foot had the same bones, +the same muscles, the same ligaments. The only substantial difference +was in the form and arrangement of these parts. Even in such a minute +particular as the three contravehent muscles in the sole of the +monkey’s foot, which draw together the heads of the metatarsal bones, +the correspondence is complete. These muscles are present and active in +the gibbon. They are much diminished in the chimpanzee. In the orang +and the gorilla they are still further reduced and closely resemble +the atrophic fibrous strands found in man. A similar correspondence +involves the muscles which separate and draw the toes together (the +interossei). They are deeply situated in the plantar surface of the +foot in most monkeys. In the orang and gorilla they have exactly the +same position and relations as in man. The human embryo affords the +final connecting link, for in this stage of development the muscles +correspond to those of the lower monkeys. + +The human foot is foreshadowed by that of the great anthropoids. It +is, in fact, the culminating stage in that series which had almost +reached the human goal in the orang, chimpanzee, and gorilla. The +plantar grooves in the feet of the anthropoid apes clearly indicate +the lines of flexion adapting the foot for purposes of grasping the +limbs of the trees. In passing from the gibbon to the orang and the +chimpanzee, with the slow development of semiterrestrial life, there +is a progressive disappearance of the plantar grooves. This change +illustrates the manner in which the foot became adapted to the purposes +of bipedal locomotion. Of all the great apes, the gorilla makes the +nearest approach to the human foot. The toes have become shorter and +have lost their finger-like resemblances. The great toe has become +larger and is partially assuming an axis in parallel with the other +toes. It has also migrated toward the end of the foot and, in older +adults, has lost much of its prehensile character. Another modification +is the gradual broadening of the heel and the appearance of the plantar +arch. All of these changes have been developed for the purposes of +bipedal locomotion and the erect posture. In consequence of these new +functions the simple grasping foot of the monkey is altered to serve as +a powerful stepping lever. In its simian form the foot is a Y-shaped +prehensile organ. The stem of the Y is represented by the long heel. +The two branches are formed by the great toe and the lesser digits +respectively. In the higher primates, such as the orang, chimpanzee, +and gorilla, the simple Y foot has undergone a striking change. +The sole of the foot, including the ball and the heel, has greatly +increased, while the toes or grasping elements have become shorter. In +gorilla this is particularly true of all the toes except the great +toe, which has not only become somewhat longer but now tends to be in +the main axis of the foot. + +The most important features in the development of the foot are the +increase in the supporting surface of the heel and the appearance of +the plantar arch. In the lower monkeys the arch of the foot is double. +In the great apes, more especially in gorilla, the plantar arch is +single and corresponds practically to that of the human foot. The +sole pads have become fused to form the ball of the foot, while the +development of the heel has caused the disappearance of the ankle pads. + +Whatever may have been the influences which caused certain members +of the prehuman stock to desert the trees and live upon the ground, +it is clear that one most important result of this change was the +formation of the human foot. This structure was a solid foundation +for the highest achievements of organic evolution. It ultimately +produced an animal capable of dominating the world. It was responsible +for all of the extensive changes incident to the erect posture--for +the rearrangement in the shape of the body, for the squaring of the +shoulders and the broadening of the pelvis, for readjustments in the +position of the heart and lungs, for new provisions in supporting the +abdominal organs, for a reordering in the relation of the eyes to +provide for binocular, stereoscopic vision, for the modifications in +the neck to suit the purposes of the most effective head movements, +for the freeing of the hands so that they might become constructive +agents, and, above all, for impressing upon brain structure the +effects of these many progressive advantages. If there could be any +doubt that the hand and the foot contributed in this decisive manner +to the development of the brain, we might test this supposition by a +pertinent question: What, for example, would the brain have been if +neither hand nor foot had made its appearance? It is clear to us what +limited advantages were acquired by animals equipped with hoofs or +paws or flippers or wings. The brain responded to the requirements of +these specialized organs. None the less, such response was always and +unmistakably the brain of an ungulate or of a meat-eater, of a flying +or of a swimming mammal. It was the brain of a creature of restricted +behaviour, as limited in the development of its intelligence as it +was in the amplitude of its adjustment to life. It was particularly +deficient in one great department which is the hallmark of all animals +possessing hands. Summarized as briefly as possible, it may be said +that what the brain owes to the hand and foot is the frontal lobe. +Through all the stages of progress, from the time when the monkeys +first began to live in the trees until their successors, through graded +intermediate phases, developed the hand and foot of man, this lobe has +been the outstanding feature of the brain. + +It is perhaps unwise and also unwarranted to speak of the debt that one +organ owes to others, especially when the activities of all represent +a unified process. Brain, hand, and foot are in the strict sense a +single functional unit. Each is indispensable to the others. Yet it +may be assumed that it was the new opportunities for action provided by +the hand and foot which at length gave the brain its human capacities. +These ultimate instruments of man’s success amplified brain power and +increased its sphere of influence. The hand in particular was the +instigator, if not the originator, of human speech. Herbert Spencer, +in his essay on “The Philosophy of Style,” clearly points out the +fundamental relation of the hand to speech, in the following words: “To +say ‘leave the room,’ is less expressive than to point to the door. +Placing a finger on the lips is more forcible than whispering ‘Do not +speak.’ A beck of the hand is better than ‘Come here.’” As the creator +of indicative gesture the hand laid the foundations for the use of +symbols, which, when vocalized, became established as language. This +attainment was the most important single step in the ascent leading to +humanity. + + + + +CHAPTER XIII + +ESTIMATES AND VALUES + +ASSETS AND LIABILITIES OF THE HUMAN BRAIN + + +There is substantial evidence to prove that the brain passed through +many intermediate stages before it acquired sufficient power to enter +upon the latest stage of its progress. Wherever it has come down +into modern times, regardless of race or climate, it bears marked +similarities in its external appearance. In spite of this strong family +likeness, however, there are many individual variations. Some of these +variations are especially noteworthy. Certain of them are of utmost +importance because it is possible to discover in them the secret of +man’s highest achievements. + +In the average human brain, as in these notable exceptions, the +principle of development remains unchanged. Expansion, the root and +base of this principle, has been most pronounced in the departments +capable of creating human supremacy. From order to order among the +mammals, increase in the size of the brain has been prominent. +Depending upon the specialization of the animal, this increase has +affected the area of vision, of hearing, of body sense, of taste, or +of smell. Only in the family of man has this expansion made itself +preëminent in the frontal region. Frontal growth is the dominant +character of man’s physical endowment. It seems reasonable, therefore, +to speak of the entire period of human existence as the Age of the +Frontal Lobe. + + +_The Frontal Lobe and the Expansion of Consciousness_ + +Selective development in the brain has had far-reaching effects. It +has provided for special adaptability. It has furnished one or more +of the senses with a particular degree of keenness. It has determined +the specific lines of reaction. These lines in all animal life express +themselves in three phases: (1) the approaching phase, (2) the avoiding +phase, and (3) the resting phase. In the vertebrates each phase depends +upon impulses which influence the nervous system, particularly the +brain. The approaching reactions embrace all efforts made by the animal +to reach out and acquire what it needs. In these reactions the hunger +impulse is the most primitive and the most important. It arises from +the necessity for food and depends upon stimuli from the entire body, +more especially from the gastro-intestinal tract. Another series of +approaching reactions takes origin in the herding impulse, which leads +to the gregarious association of animals of the same kind, such as +schools of fish, flocks of birds, herds of cattle. The stimuli for this +impulse come through the contact-receiving organs. Many approaching +reactions express the essential necessity of the muscles to contract, +as in activities without any other apparent objective. Still more +conspicuous are the approaching reactions caused by the mating +impulses which arise from sexual stimuli. + +Impulses of each variety motivating these reactions of approach +ascend higher in consciousness, or acquire greater clarity, in direct +proportion to the brain capacity of the animal. Consciousness in fish +is of a relatively low grade. It becomes progressively more extensive +in amphibians, reptiles, birds, and mammals, reaching its highest +development in the human cortex. The frontal lobe in man provides for +an incalculable expansion of these impulses in conscious clarity. + +The avoiding reactions of animal life likewise depend upon fundamental +impulses whose essential stimuli arise from the hurt or painful +elements in sensation. All extremes of sensory stimulation may +contribute to impulses underlying the avoiding reactions. They form +the natural armament of protection upon which the animal depends in +adjusting itself to its surroundings. As in the case of the approaching +reactions, so the impulses necessary to avoidance are progressively +expanded through the vertebrates until they reach their highest clarity +in the human brain. The resting phase depends upon impulses derived +from the entire metabolism of the body. + +These fundamental impulses which become clearer in consciousness +through the progressive stages of the animal kingdom tend to interact +in their correlations and determine combinations of great importance. +Avoiding impulses of a protective nature may combine with approaching +impulses to determine a reaction of attack in order to save the +animal from some threatening enemy. Thus a protective effort may be +a combination of an avoiding and an attacking attitude at the same +time, as when the mongoose, jumping backward in retreat from the +striking cobra, still maintains the pose of attack in the entire set +of its body. The resting phase may be employed as camouflage for an +avoiding reaction in what is commonly known as “playing ’possum,” or +it may be used as a decoy in preparation for aggressive activities of +attack, particularly as seen in the cat family. In man the range of +these combinations has attained the highest degree of development. The +frontal lobe furnishes an extensive equipment for this purpose. In +all modern races frontal capacity manifests but little difference. It +therefore seems clear that this common denominator of human success has +given man his power to hold his place in nature and to overcome the +difficulties which have beset his path. + + +_Caucasian Supremacy_ + +The greater apparent successes of the white race might presuppose a +greater degree of brain capacity and hence a better frontal lobe. But +the frontal superiority of the Caucasian peoples, if it exists, is at +best slight. The white man’s supremacy must, however, depend upon some +actual advantage. Although outnumbered two to one, he is to-day the +overlord of the world. Of the 1,700,000,000 human beings now living, +only 550,000,000 are Caucasians. The remaining 1,150,000,000 belong +to the yellow, black, and red races. In spite of this disparity, the +white man’s policies, his products, his projects, penetrate into every +angle of the earth whose climate, fertility, or hidden wealth may be +exploited by resources of the Caucasian brain. + +Numerous facts indicate that in the white race there has been +an unusually large number of individuals with exceptional brain +development. Many Caucasians who have distinguished themselves +intellectually show conspicuous advantages in cerebral development, +especially in the richness of convolutions and fissures. The region of +the brain showing this richness particularly is the frontal lobe. + + +_Brains of Modern Races_ + +This lobe is much the same in all modern races of men. The Eskimo +brain, however, possesses frontal convolutions which are rather more +complex and tortuous than in the average whites (Hrdlicka). As a +whole, the brain of this northern race is heavier and larger than the +Caucasian. Its excess of weight over the average white man, according +to many observers, amounts to about 150 grams. The large Eskimo brain +is not out of proportion with the fact that these people are compelled +to contend with an exacting environment and require much ingenuity to +maintain themselves. + +The brains of the aborigines in Andaman and Nicobar Islands weigh +somewhat less than the average white brain. The brain is broad and +short; the frontal lobes are a little less massive than in the +Caucasian. The fissures and convolutions are, if anything, slightly +less complex than in the white man, although the difference is not +striking (E. A. Spitzka). + +The negro brain, for the most part, has the same outline as the +European brain (Tiedemann). The length and height of the hemispheres +do not differ visibly, and their breadth is only a little less. The +convolutions are large in the frontal regions and the sulci show a +greater degree of symmetry than is usually found in European brains. + +Among the American Indians the average weight of the brain is somewhat +less than the Caucasian (H. B. Ferris). This is true both of the +North and South American Indian. On the other hand, the fissures and +convolutions, especially in the frontal region, correspond very closely +in complexity and dimension to those of the white man. + +Examination of Mongolian brains shows that the average weight of the +Chinese brain is slightly less than that of the Caucasian (Kurz). +The Chinese brain is said to have a number of striking peculiarities +in which it differs from the brain of other races. One investigator +mentions thirty-three peculiarities of this kind, and yet when each +peculiarity is considered individually its prototype may be found in +an extensive group study of Caucasian brains. The frontal lobe is +richly convoluted and fissured. Kappers believes that the Chinese brain +retains a degree of infantilism, much of which is shown in the high +arching of the corpus callosum. + +Accepting all of these differences in the several races of living men +as to weight, dimension, development of lobes, richness of convolutions +and fissures, and peculiarities in individual details, it becomes +clear that such differences as do exist are slight enough to be well +within the range of individual variation. In other words, when large +numbers of brains of the several races of modern men are compared, +the differences between them are almost certain to assume no great +importance. We may conclude that the Caucasian, Negroid, Mongolian, and +all other forms of the modern brain present a striking similarity in +their general appearance and characters. + + +_Brains of Distinguished Men_ + +When, however, we consider the brains of distinguished members +of the white race, we at once obtain the impression of striking +individual variations. The brains of many men of genius have been +carefully studied. Spitzka has collected the records of one hundred +such individuals to which he has added his own studies upon six +distinguished scientists. All tell the same story. These men, noted +as jurists, scientists, mathematicians, composers, dramatists, +physicians, journalists, statesmen, and historians, have with few +exceptions possessed brains which in weight exceed those of the rank +and file of the race. This is true of the brain of such outstanding +men as Beethoven, Cuvier, Turgenev, Daniel Webster, Lenin, Thackeray, +Joseph Leidy, William Pepper, Edward Cope, and many others. The brain +of the remarkable deaf, dumb, and blind girl, Laura Bridgman, has +been carefully studied by Dr. Donaldson. It is notable that in this +instance the frontal lobes, both in size and in the richness of the +convolutions and fissures, were well developed. It was in this region +that the brains of the distinguished contributors to human progress +already mentioned showed their greatest degree of expansion. Recently +reports on the brains of Sir William Osler, of Dr. G. Stanley Hall, +and of Dr. E. E. Southard have been published. In each of these +remarkable men the size of the brain and the unusual development of +the frontal lobe have been striking features. The brain of the great +German historian, Theodore Mommsen, was particularly notable because of +its frontal development, and so also was that of William Bunsen, the +scientist and discoverer. + +In contrast to the massive brains of these other men of genius, there +has recently been brought to light the fact that the brain of a great +modern master of literature, Anatole France, was remarkably small, +weighing only 1017 grams. This weight is considerably below the average +for the white race (1300-1400 grams) and not much above the estimated +weight of _Pithecanthropus erectus_, the Java ape man. The difference +between the weight of Anatole France’s brain and that of the ape man is +77 grams, according to the estimated values. Sir Arthur Keith maintains +that in spite of this noted academician’s reputation, known the world +over for his writings as a novelist, philosopher, and savant, Anatole +France was actually an extremely primitive man. This position taken by +Keith would be difficult to support against the prevailing opinions +of the day. We should be more impressed by the degree of richness in +development of the frontal lobe and the complexity of its convolutions +and fissures than by the actual size of the brain. It would seem +most likely that a marked degree of frontal development has been the +decisive factor in the production of the exceptional brain. Most of the +great men who have left records in respect to their cerebral endowment +confirm Sir Arthur’s contention that a powerful brain is a large brain. +Individual variation may account for much, however, and a high grade +of frontal convolution, implying as it does a great cell richness +in a cortex, may make amends for many ounces of weight deficiency. +From the facts available it is clear that human greatness in the main +depends upon largeness of brain and extensive frontal development. The +possessors of such brains have been the leaders in the activities of +the white man, in every line of his progress, in every detail of his +success. They have been the Caucasian thinkers, the idealists, the +philosophers, the poets and artists; they have been the white man’s +pragmatists, his statesmen and builders of empire. They have also been +his spiritual pioneers, the founders of his religions and ethics. To +them has been given exceptional power of vision, with equally great +capacities for transforming what such vision revealed into benefits for +their race. + + +_Caucasian Leaders_ + +History gives them their proper places. Their dynamic personalities +have touched the earth and made it bring forth its seven wonders and +an increasing multitude of lesser wonders, each a marvel of human +ingenuity. As they touched the earth and made it produce, so they have +touched the hearts and imaginations of their fellow men until their +minds responded to new aspirations and nobler purposes, until the mark +of the beast was left farther in the distance and the ascendancy of +mankind became the most stirring theme of creation. + +History also shows how these favoured elements of the race, under +the guidance of their leaders, have built brilliant civilizations, +compelling systems of religion, far-reaching codes of ethics. Nations +have risen, articulating the ideals of peoples scattered over vast +territories. Cities have come into existence filled with the treasures +of man’s imagination. The same aspiration shone through them all. It +was the spirit, the determination to reach out where man had never +reached before. + +Whatever were his material successes, still more important was that +inner possession which came to man during his adventurous development +of civilization. However simple it may have been in the beginning, it +grew rapidly. This priceless possession was the human intellect. In +many tribes of men it manifested none of the expansion discernible +in the more progressive races. But with its fullest opportunity, +especially under the conditions of European environment, it developed +to the degree which created a new humanity. Man recognized his +interdependence with his fellow beings. His social qualities now began +to bear fruit in a new soil and in a more invigorating atmosphere. The +finer traits of his social nature grew abundantly. Broader conceptions +of responsibility to others, deeper understandings of sympathy, led to +new products of generosity and new vocations of social devotion. All of +the higher sentiments found easier means of expression. These were new +conceptions denied to lower animals and to the lower races of man. + +Scarcely less substantial than the satisfaction derived from this deep +social sentiment was the gratification obtained from an appreciation of +the beauties of nature and from man’s own efforts to duplicate these +beauties in his art and literature. But his eyes have never contented +themselves with earthly attractiveness alone. When he had possessed the +earth he must still reach out in imagination to gain for himself the +assurance of kingdoms beyond his present state. In all his civilized +period and even long before man has peered acquisitively into the +unknown, to create for himself a future existence or the hope of such +existence. This yearning for another and an immortal life has been +the basis of his many religious beliefs. From this theme of religion +have grown the impulses for the best of human achievements. It has not +merely formed a halo about civilization, but has reached far inward to +exert control over almost every human relation. No influence has been a +greater force in the ennoblement of life. No creation of the brain has +been a more effective guide in directing human destiny. No incentive +has sustained human hope more consistently than the solace arising from +this deep source of faith. + + +_Age of the Frontal Lobe_ + +The frontal lobe, which has guaranteed such advantages to man, +brought him his spiritual understanding, his social attributes, and +his satisfactions from art and literature. It created the means +for him to gain a more adequate knowledge of the world in which he +lived and of the great cosmos of which his world is but a part. The +conquest of reality, the deeper appreciation of things as they are, +the broad expansion of his knowledge of all things in and about him, +have contributed deep satisfactions to human life. It is difficult +to estimate in this day the value of all the great contributions to +science. It is difficult also to state which product of man’s frontal +lobe, his social development, his religion, his art, his literature, +or his science, has meant most to the growth of that imposing figure +in which he now presents himself. No one of these elements may justly +deserve to be set above the others. Deprived of any of them, the +race might have been seriously impoverished; it might never have +attained that position which entitles it to be considered the supreme +achievement of creation. It is little wonder that the gods which man +set up for himself have been anthropomorphic, cast in his own image and +likeness. + +In later days there were reasons for the Caucasian’s assurance, for +his self-reliance, for his faith in his own judgment and reason. Peace +and comity existed between the nations of the earth. Prosperity was +within their borders. Success and progress filled every walk of life. +Social order rested upon firm moral foundations. This was a human +establishment upon which to depend. But ultimately this record of the +white man, from the beginning of his civilized period down to the early +decades of the Twentieth Century, brings us to a fateful midsummer day, +the 1st of August, 1914. + + +_Old Sores and Liabilities_ + +Perhaps there are no good reasons for turning back to such old +sores. Can any conceivable advantage come of opening again those +vaults holding that which we would rather forget? With passing years +memory gradually relinquishes what should be the immortal lessons of +experience. The horror, the degradation, and all other outgrowths of +the protective mechanisms making for better judgment, for saner living, +for wiser avoidance, are soon forgotten. We look and see only the +whited sepulchre. The dissolution and disease, the lurking danger for +the future, are concealed. Yet these are our liabilities. If we drive +on blindly or with our eyes closed to them, such prosperity as we have +attained is destined to disintegrate. + +It is the old formula over again that we see beginning to reproduce +itself on that fateful August afternoon. The expansive demand for +power, the will to dominate, the insatiable determination to possess, +are all disdainfully snapping their fingers in disregard of the rights +and peaceful pursuits of others. Sacred obligations are thrown to the +winds with the crackling of a scrap of paper. There are no obligations. +Lust, greed, and the dregs of human cruelty are seething in the +breasts of men turned animals, are ready to speak with the tongues of +every manner of ruthless torment. By armies men return to the filth +of the earth, living in the mire, breathing the stenches of their own +corruption, inhaling the gases of sadistic invention, meeting the flame +of an earthly purgatory, and inspired by the single indefatigable +impulse to kill. And for what purpose? None but the old one! To grasp, +to gain, to seize by force! There is no question of right or wrong. The +only question is right of possession. Both those who attack and those +who defend pray to the same God and pray the same prayer. + +Here in our own days is the frontal lobe leading a great fraction +of the white race not merely into hell but to the brink of its own +undoing. If it failed in this leadership it was by the narrowest +margin. It has left us still gasping on the edge of the precipice into +whose depths we have gazed, wondering how long ere we see them again. + +Courage, endurance, and heroic determination we say were the +compensating atonements for this madness, for this maniacal era of +wanton destruction. Nobility of purpose rang out in the defiance--“They +shall not pass!” Yet where was the nobility in that machine-made death +which swept regiment after regiment into oblivion by its withering +fire? Who now will claim the glory of 400,000 dead in less than a +lunar month, of 8,543,515 fighting men fallen in the early prime of +manhood in four years of war? Is this the chronicle for a great race to +glory in? It is rather the record of the white man at his lowest ebb, +dehumanized for a mere bauble of possession. + +Thus, through four brief years, out of the unhallowed precincts of no +man’s land, the mark of the beast came back. The white man learned +that the cloak over his baser passions was a thin veneer. He learned, +or may have learned if there has yet been time to recover from the +overwhelming concussion, that he is not yet master of himself, that +the chief guide of his life may on slight provocation lead him not +rightly or well, but with unerring precision, into the pitfalls of +extermination. + + +_When the Pressure Comes_ + +We speak of loyalties and vocations of devotion. Where are these when +the pressure comes? Where are they when the man stands with his mob? +The greatest and best things in life at once take flight. There is not +even standing-room for them when hate and revenge are the passions of +the day. It is then that class stands against class. All that wealth +and culture and luxury have built through centuries finds no strength +against the ire galvanized by equal centuries of oppression. Those who +have suffered their silent agonies confront those who are about to die. +Such have been the tragedies of revolution. So it was in the French +Revolution, with its history of guillotine horrors. Such was the case +of Russia in revolt. Such it has always been wherever the privilege to +enjoy, concentrated for the benefit of the few, has worked disadvantage +to the many. Neither those who for the time enjoy, nor those who +are deprived, have sufficiently learned the lessons of moderation, +self-restraint, and control over the human spirit to hold in check the +baser impulses. + +War, revolution, and other mass reactions in the interest of +readjusting man’s social conditions are not rare in our racial +experience. Since the beginning of historic times there have been +thousands of wars of greater or less magnitude. If, during the Roman +era, the gates in the temple of Janus stood open for centuries and +that great people were almost continuously at war without appreciable +cessation, we moderns would have no need for an energetic gatekeeper. +In one place or another, throughout the globe, we have been +continuously waging war or producing revolutions. Following the close +of the great World War, a little more than a decade ago, there have +been no less than sixteen wars, and seventy-five thousand men have died +as a result of warfare. Let those who philosophize in security call +war an activity essential to human progress. Those who know it through +suffering and loss will call it by its proper name. It is not, however, +in war alone that we may discern the results of our defective control +over human nature. We need turn but a few pages of history to encounter +many other sore spots. Among these blemishes are those arising from +a source which should have been our most unfailing, our deepest +consolation. + + +_Heresy and Retaliation_ + +The spiritual heritage bequeathed by the Great Galilean retained +its influence for little more than two centuries. Through the dark +Middle Ages Christianity wandered far from the path of its appointed +blessedness. To many it ceased altogether to be a blessing, and to +many others it became an actual curse, meaning for them torture, +imprisonment, starvation, humiliation, or death by burning at the +stake. There can be little wonder that heresies sprang up against the +inhuman conduct of the mediæval Church. Corruption, discrimination, +demoralization, abuse, and tyranny went unrebuked. The church +militant was infected by every sin that it was created to prevent. +Heresy was the reaction to such corruption, and the Inquisition +was the retaliation on the part of the Church to preserve itself +against heretical disintegration. The barbarous zeal which through +many centuries brought misery to mankind in the name of Christ has +been explained in several ways. Some have denounced it as mere +bloodthirstiness or lust of power. Some have traced it to the doctrine +of exclusive salvation. In order to understand it properly we must +comprehend the stage of civilization in which it flourished. The feudal +military spirit was everywhere dominant. Society relied more upon +force than upon persuasion. Industrial influences had not yet tempered +modes of thought and action. Throughout the Middle Ages men were +strangely pitiless in their dealings with each other. The wheel, the +cauldron of boiling oil, burning alive, burying alive, flaying alive, +and tearing apart with wild horses were the ordinary means by which +jurists endeavoured to deter crime. In England poisoners were boiled to +death as late as 1542 (Rouse and Margaret Davie). One woman, in 1726, +was burned at Tyburn. Minor crimes were dealt with with a harshness +unbelievable in this day, including such hideous procedures as +blinding, mutilation, tearing with hot pincers, breaking on the wheel, +and cutting out the tongue. People of all nations were accustomed to +this cruel savagery and accepted it in relation to crimes that were +thus punished. By popular detestation heresy was regarded not merely as +a sin but as the worst of all crimes. This belief was held with equal +tenacity both by the clergy and the laity. Under the influence of such +feelings the Church adopted the harshest measures and continued to grow +more cruel and more unchristian. + +The Inquisition was not a local phenomenon. It became most intense in +Italy, where it gradually took shape. In time it spread into Germany, +into France, and into Spain. The Spanish Inquisition was employed for +the most part as a state institution to maintain the throne. It used +all of the ingenuity known to the ecclesiastical inquisitors and added +punishments of its own. The torture chamber, which at first was not +introduced as an inquisitorial instrument, soon established itself +as an indispensable accessory and flourished in many parts of Europe. +There was a furtiveness in the manner in which the Church doled out +these punishments. For the repentant heretic life imprisonment on +bread and water and in chains was not a criminal sentence; it was the +means of repentance and salvation for the unfortunate sinner. If the +heretic remained unrepentant the Church washed its hands of him as a +capital offender and turned him over to the secular authorities to be +burned at the stake. The dungeon in which the unfortunate victim was +imprisoned for life was a frightful chamber, damp, and infested by rats +and vermin. Confinement was solitary and various circumstances besides +pain and hunger were brought to bear upon the terrorized imagination +of the prisoner. These dungeons were often ingenious means of torture. +One in the Bastille at Paris had a floor which was conical and pointed +downward so that it was impossible to sit or lie in it. Another in +the Châtelet had a floor continually covered by water, compelling the +prisoner to stand erect. Persons convicted of heresy were also forced +to wear crosses of cloth, generally yellow, sewed upon their garments. +In this manner the symbol of Christian devotion was converted into a +badge of utmost shame. Confiscation was another penalty with frightful +effects. Upon arrest for heresy a man’s property was sequestrated, +and his family thrown into the street. After several centuries of +unremitting cruelty the Inquisition succeeded in suppressing the +various sects of heretics. For this advantage the Christian Church +paid an unnecessarily high price by gaining for itself a lasting stigma. + + +_Provocations of Circumstance and Time_ + +Such interludes as these in the course of man’s happiness and peace +may perhaps be regarded as unfortunate digressions from the scheme of +human behaviour. Their apology lies in the fact that they belong to +other times by contrast with which we have shown great improvement. We +are much changed for the better--so much changed that many of these +appalling episodes of history could not occur in this day. Reassurance +of this kind may comfort us, but it does not provide us with protection +against ourselves. For with due provocations of circumstance and +time there is no guarantee that we would not repeat or even amplify +the ghastly delinquencies of the past. The pride we feel in our +modern progress and prosperity elevates us to a plane of conscious +superiority. And yet this same pride experienced a sickening collapse +when no later than our own day and generation it was forced to witness +a phenomenon of eruptive brutality compared to which all former warfare +was insignificant. In spite of this recent experience we feel sure of +ourselves, confident in the great capacities which have made us men. +We possess this confidence, however unenlightened we may be concerning +the real power upon which we depend, especially as to its source, its +nature, its possibilities, and its proper management. + + +_Compounding the Essential Impulses of Life_ + +As no other members of the animal kingdom, we have compounded each +one of the essential impulses of life. Through our frontal mechanisms +we have raised these primitive drives to the most elevated planes of +consciousness. We have increased their clarity to the highest degree. +It was doubtless the introduction of symbols which first secured this +greater clarity. Later the development of spoken language established +the universal medium of exchange within the brain. Lower animals +evidently do not learn to speak. They only acquire the use of beast +cries by which to transmit warnings, sex invitations, or challenges to +combat. Such specific cries modified by the structural adjustments of +man may have been sufficient for the simple human language of earliest +times. There seems to be no actual barrier between the vocal activities +of birds, dogs, apes, and men except that superior mechanism of speech +provided by a progressively developing frontal lobe. From its first +introduction language was a societal phenomenon. All of its products +were likewise societal. If it raised man as an individual, its greatest +profits appeared in the elevation of the social order. Under this new +influence the primitive impulses of hunger, herding, mating, avoiding, +and the rest entered into complex combinations. In consequence, each +primordial drive was converted into a thriving industry in the interest +of further human satisfaction. Excessive growth in these industries +soon manifested many dangerous tendencies. New human expansions +developed out of the primitive impulse of hunger under the added +opportunities of the frontal lobe. Appetite and indulgence with their +tendencies toward excess came in conflict with sumptuary restrictions +and prohibitions. The effects of frontal expansion upon the herding +impulse contributed to the development of crime, to the creation of +mass phenomena under the influence of fear, hate, and hope, to the +epidemic spread of group manias and popular delusions such as were +the pilgrimages, crusades, and demonism of the Middle Ages, such +as was the extremity of ruthlessness manifested in the last great +war. The extension of the sex impulse through the mechanisms of the +frontal lobe is incalculable. From it have come crops of asceticism +and licentiousness, of poetry and sentimentality, of social order and +disorder, of philosophy and pure bunkum. The expansion of impulses +underlying the avoiding reactions has produced an unescapable blight +upon human life due to the extensive corticalization of fear. The fear +of bondage or slavery, of tyranny or cruelty, is no longer upon us. +A multitude of more subtle fears, engendered by modern civilization, +have produced our phobias, our irresistible compulsions, and our great +variety of somatic and psychic anxieties. + + +_Human Nature Has Not Changed_ + +The incentives of life have been magnified and multiplied upon the +screen of the frontal cortex. They have afforded man his powers of +judgment and reason, his greater capacities to enjoy existence, his +new aspirations of hope. They have supplied him with his broader +opportunities to order and adjust his life and with his stimulating +inspirations of learning. Each of these new capacities is conditioned +by the circumstance and fashion of a given age. There is no arguing +with such fashion. The _mores_ and the times, the customs and the +place, dominate the products of the frontal lobe and mold them in +constantly changing patterns. The fashion of yesterday is often +the laughing stock of to-day as that of to-day may be the jest of +to-morrow. These plastic patterns, which the frontal lobe produces +for the conduct of human affairs, have neither permanency nor assured +foundations. Great principles which we swear by now we know are wholly +transitory. While they last certain moral notions and devices are in +fashion, but these are conditioned by the times and customs. In such +facts as these may be recognized the variable quality of human wisdom. +Reason is likewise based upon conditioned reflexes which have grown out +of the _mores_ of the time and place. In this light, if man seems to +have come a long distance from his early beginning, the path measured +in units of real progress is surprisingly short. “Things happen,” says +Sumner, “which show us that human nature has not changed and that the +brute in each may awake at any time. It is all a question of time, +custom, and occasion and the individual is coerced to adopt the _mores_ +as to these matters which are then and there current.” + +Morals and manners, like speech, are societal adjustments. They are +highly conditioned reflexes acquired through generations of social +experience. Self-restraint, agreeability, and coöperation form the +basic currency of successful social intercourse. They are the artifacts +of group needs, the medium of exchange in all comfortable and safe +contacts between man and man. That these qualities are superficially +engrafted upon human nature is easily demonstrated. With adequate +provocation the individual discards restraint and reveals the grossest +traits of his aggressive reactions, the group is quickly resolved into +the lawless mob, and nations are easily excited to martial frenzy. + +What benefits, therefore, will we obtain by further self-deceptions? +It is long overdue that we see through the thin fabric of traditional +delusions wherewith we have surrounded ourselves. It requires courage +to face the truth and an open mind to recognize it. But we cannot hope +to improve unless we see ourselves as we are, unless we appreciate our +inherent liabilities as well as our assets, unless, divested of angelic +or godlike disguises, we stand forth for our own inspection as human +animals occupying the foremost place among living things only by virtue +of the best brain thus far developed. Much that is animal within us +must remain unchanged despite our utmost strivings. All that is human +may be modified, enhanced, and brought to better fruition. + + +_Handicaps and Restraints_ + +Almost from its beginning the race has recognized its handicaps. It has +struggled in many ways against its own liabilities, especially those +due to increased brain power. By systems of philosophy the human spirit +has sought to show the reason and goal of life, has endeavoured to +envisage the most desirable pathway for existence. + +Man has endeavoured to hold himself in check through religion, bowing +to the belief that for every human being there is some higher power +controlling destiny and for this reason entitled to obedient reverence +and worship. For his hour of need, however, philosophy and religion +offer no reprieve. The Great War comes, and assurances from these +sources of human reliance have no power to stay the catastrophe. + +Man has experimented through societal organization, through the +formation of governments, through the establishment of laws, to +restrain the dangerous tendencies of his frontal lobe development. But +if his governments succeeded in utilizing effectively his efforts at +social order, they have also abused these efforts. In every societal +system there must be a ruling class. According to Professor Sumner, +no class can be trusted to rule society with due justice to all its +members. Whatever the sins of antiquity, modern society is ruled by +the middle class. It has to its credit the invention of institutions +securing civil liberty and the safety of person and property. Its +history is otherwise not satisfactory. It has demonstrated that in no +popular government could sufficient control be created to restrain the +abuses of special privilege, to avert the corruption of civic power +for graft, or to repress the selfish undertakings of cliques formed on +special interests for the purpose of public exploitation. When faced by +this test, all modern democratic states have failed. Plutocracy and the +unscrupulous powers of wealth are at the root of the financial scandal, +which is the blemish upon all modern parliamentary organizations. We +must recognize this defect not merely as a tendency of the times but as +a national disease. It spoils every institution and, extending from one +generation to the next, at length destroys in the masses the faculties +of ethical judgment. + + +_The Cult of Success_ + +By education man has likewise endeavoured to moderate the recognized +liabilities of his frontal lobe. But, like his customs, his education +has varied with the fashions of his time and place. With one brilliant +exception educational processes have too strictly been confined to +technological training, or to the inculcation of traditional cultures +or mediæval scholasticism. The ancient Greek alone dealt with his life +and its problems as we well might with ours. We are imitators and large +users of secondhand materials. He was an originator. His education was +an adventure of discovery, an absorbing search for the understanding +of what constituted the good life. Largely without traditions and upon +his own initiative he endeavoured to gain a critical attitude toward +all of his prejudices, to liberate himself from the dominance of herd +influence, and to adjust his conduct most intelligently for the welfare +of the state. + +Modern education is especially in a state of confusion. It is almost +wholly devoid of any broader theme than that embraced in the purpose +to teach the individual the formulas necessary to make good. There +is little effort to inspire a larger point of view, to instill an +understanding of life’s values, an appreciation of its relations, and +of its truly human opportunities for intelligent living. + +Philosophy, religion, societal order, government, and education have +failed to produce any entirely satisfactory solution of life. They have +scarcely recognized the existence of the frontal lobe, but, looking +beyond it to some intangible sources of power, they have neither +capitalized its assets nor reckoned with its liabilities. There is +probably a cause of long standing behind these several failures. For +centuries and ages the incentives of human efforts, even the best, have +laboured under a contaminating influence. This influence has touched +and tainted every aspect of life. During thousands of years men have +struggled to make good in Europe. The result has always been the same. +From time to time some section of the race has succeeded, later to +weaken, and in the end to succumb. In the past an invariable cycle of +rise, decline, and fall has dictated the course of life in Europe. +Such was the lot of the Neanderthals. Cromagnon and Neolithic men both +had their days of success and of disappearance. It was not different +with the Greeks or the Romans who rose and finally, under this spell +of Europe, passed into decline. In many respects the motive at work in +this destructive cycle seemed to act like some evil influence. It was +already well developed in the first trading exploits of the Phœnicians. +With them it began to migrate westward from harbour to harbour along +the Mediterranean. It implanted the germs of its spreading infection, +which came to be the dominant spirit of civilization--gold and a price +for everything. Nothing escaped the effects of this new standardization +of human enterprise. The pioneer Phœnicians carried this gold standard +of life far beyond the Pillars of Hercules to the shores of Britain +until it spread throughout Europe. The source of this influence +lies far back of these earlier civilizations. It had its origin +in those primitive days when Mousterian cave man tasted the first +drafts of power. The use of this power he justified by one standard +only--success. For three hundred thousand years the human brain +has been conditioned by this influence. Power increased, successes +multiplied, and the passion for possession became a frenzy. Thus it +was that those whom the gods would destroy they first made rich; and +thus also one civilization after another met its destruction. No other +solution can be worked out on this standard of existence. It will serve +to exploit nature, including human nature. It may bend the natural +forces one after another to man’s bidding. It may make him master +of the entire world except in one superlative detail--himself. In +proportion as it has been concentrated upon the conquest of the earth, +it has had little time for the mastery of the spirit. The old idea +is still at work with us to-day. We have found nothing new, nothing +better. We scarcely attempt to look. It is now our ruling passion. It +has been the contaminating influence which has for ages frustrated the +best human efforts. + +Wealth, with the power to confer upon the greatest number the benefits +of true human satisfaction, is not to be condemned. Its acquisition +and proper distribution must be intelligently encouraged. Such wealth +is the just return on man’s efforts to make and maintain for himself +a wholesome place in nature. But riches, representing egocentric +aggrandizement and the upbuilding of special privilege for selfish +ends, are an open sore in all times and a most serious menace for the +future. + +The ancient motive of possession is still the most powerful urge among +civilized peoples. It has exerted an increasingly evil influence upon +modern times. Its effects have been unfavourable because possession and +power depend upon the offensive and defensive mechanisms of aggression. +Such mechanisms are the progenitors of war. They promote the conflicts +of social rivalry between classes and incite the struggles for +competitive supremacy between nations. If the goal of such life is +success, the price of such success is strife. This is the standard +of existence which has prevailed for at least three hundred thousand +years. It seems irrevocable. Nothing visible in our modern world +suggests the cessation of its destroying influence. In the absence +of any present reassurance there is a strong probability that we are +following, to its bitter ends, a path long familiar to our race. + + + + +CHAPTER XIV + +THE FINAL TEST OF THE BRAIN + +WORLD COÖPERATION AND RECIVILIZATION + + +Our most vital issue is no longer a matter of national prosperity +alone. The success and therefore the happiness of the entire world are +at stake. This generation of ours has taught us what to expect from the +old forces of competitive wealth and nationalism. It is not difficult +to foresee the recurrence of one war after another. As Dr. Butler has +so forcibly said: “The world is just now standing at a crossroads. +It may take the path in one direction and so make agriculture, +industry, commerce, trade, finance, the fortunate means of uniting +the whole world, of increasing its prosperity and of buttressing its +peace; or it can take the opposite path and so turn the nations into +narrow-minded, unsympathetic, jealous, and quarrelling neighbours, +and prepare the way for another cataclysm which, if it should come, +would mark civilization’s end. What are we going to do about it? Where +shall our influence be thrown? Shall it be for a repetition of the +old stupidities, the old ignorances and the old antagonisms, or shall +it be for a new world order in which selfish competition shall be +supplanted by kindly and large-minded coöperation? That is in substance +the crucial question which at this moment awaits answer by leaders of +opinion in every land.”[1] There are many who believe that man in +his present exalted phase cannot stand the test. His modern days are +numbered just as surely as were those of his ancient glory. He has no +further reliance, no better assurance now than he had then. The fate +of civilization hangs in the balance; its chances in many respects +are unpromising. There are no guarantees for the future outside of +man himself. Although we have multiplied in number and compounded our +problems of life, the world in which we live is much the same as it has +been for hundreds of thousands of years. If man also remains unchanged +we may expect the same lot which befell other successful people in the +past. + +[1] From “The New Center of Gravity,” an address delivered at the +Parrish Art Museum, Southampton, L. I., on Sunday evening, September 1, +1929, by Nicholas Murray Butler. + +And yet looking beneath the surface and into the depths of the organ +which has been the chief asset of our progress, we may discern +some promising possibilities. These are possibilities which if +developed might subordinate or overcome the ancient lures of power +and possession. They might even establish a new order of existence, +a new age of wisdom, with clearer ways of looking at life and better +methods for realizing its opportunities. We may have no desire to see +these possibilities. We may turn from them now as we have before. They +clearly exist, however, and chief among them is the possibility of a +better human brain, a brain with much more ample power by means of +which to create a better world. + +Many facts support this possibility. We know from certain evidence that +man in his earliest period on earth possessed a brain much simpler than +that responsible for his modern successes. Such testimony is given by +the brain cast of the Java ape man. The entire cerebral structure in +this instance was in an intermediate phase of human development. It was +far in advance of the brain of the highest apes but much less developed +than the brain of modern men. In spite of its simplicity it gives +evidence of human progress. It had supplied the structural basis needed +for a crude type of humanity. It indicates that the powers of human +speech had been acquired and that the first steps in the upbuilding of +human intelligence had been taken. + +Compared with this primitive race of extinct men, the Piltdown and +Rhodesian brain casts bear signs of definite progress. With the passage +of time brain power continued slowly to acquire new capacities. +Nothing makes this conclusion more certain than the facts revealed by +the Neanderthal casts. From them it is clear that the chief organ of +life which directed the successes of the Neanderthal race had assumed +many aspects of modern development. Most of this progress in the +brain during its gradual stages upward, through the ape man, the Dawn +man of Piltdown, the Rhodesian, and the Neanderthal, manifests its +highest degree of expansion in the frontal lobe. With the coming of the +Cromagnon race all of the cerebral requirements necessary to modern +man made their appearance. Thus through more than a million years the +brain has slowly improved. There has been a steady increase in the size +and richness of its convolutions. + +In contrast with the lifetime of other families in the animal kingdom +the human race has scarcely passed out of its early youth. Our race +seems young as the ages of the earth are estimated, and our racial +youth justifies the belief that the modern brain represents some +intermediate phase of ultimate development. The facts of the distant +past point ahead to periods of further progress in the future. +Influences which have operated through vast intervals of time in slowly +advancing the brain from one stage to the next are doubtless still at +work. The impulses necessary to brain development had their beginning +in the fishes. They continued through reptilian and mammalian phases +and finally passed into the period of tree life wherein the foundations +of the human brain were laid. It is difficult to believe that this +impetus of progress which persisted for ages has at length ceased to +act. + +The possibility of a better brain finds support in another fact of +great interest. An entirely new force favourable to progressive +development has made itself felt within the last century. Never before +has it exerted an influence upon the process of evolution. At present +it is difficult to estimate its full value as an element of progress. +This new force arises from the fact that men and women throughout +the world have recognized the existence of an evolutionary process. +In all places where the earnest search for truth is being made this +knowledge has become the dominant note. It cannot fail to lead to +new understandings and to add new quota of power to the organ of our +chief reliance. An adequate appreciation of the processes underlying +natural selection is certain to impart new and practical significance +to the survival of the fittest. The means which may subsequently be +employed to further such survival cannot be predicted. Whatever they +may be, if they justify themselves by advantageous results, they will +be applied with courage and intelligence. They may embrace measures of +extensive restriction and intensive selection to meet the conditions +of overcrowding in population, and of inequality in the emoluments of +life. The embarrassments of the laggard fractions of humanity would +thus be overcome. + +Application of wise societal regulations having as their object the +better apportionment of opportunity and the greater accessibility of +human happiness might easily be conceived as the outgrowths of such +further extensions in knowledge. Obviously the questions concerning the +character of the means directed to these desirable ends cannot now be +discussed or foreseen. It is sufficient to indicate that whatever these +agencies may be, provided their results are calculated to contribute to +the betterment of mankind, they may be discovered and made practical. +This possibility presupposes the attainment of those advantages which +accrue from a better understanding of man as a participant in a still +active process of evolution. + +If up to this time we have employed the full power of our intelligence, +if we have made the best use of the brain, there may be actual +doubts concerning further progress. Many reasons justify the belief, +however, that the human race has not yet utilized the brain to its +fullest capacity. Numerous facts support this view and make it +appear certain that we have developed but a small fraction of our +potential brain power. In exceptional cases of outstanding groups and +highly specialized individuals the brain may have yielded something +approaching its best product. Even in cases of unusual development +there are deficiencies and inequalities of development due to the +circumstances of training, to the introduction of adverse influences, +and to the universal lack of any generally acceptable goal of life. +A cross section of any community estimated by its high and its low +intellectual attainments indicates a striking unevenness in brain +development. It also reveals a low rating in the average intellectual +level. Averages of this kind obtained from nations or races disclose an +aggregate of brain power far below the grade of the brain’s potential +capacity. Instances of individual specializations make the fractional +development of the race still more evident. If, for example, Laura +Bridgman, deprived as she was of sight, hearing, taste, and smell, with +only a fifth of her brain areas accessible to satisfactory contacts +with the world, made an adjustment to life equal to the average of +such adjustments; if Helen Keller, almost equally deprived of sensory +impression, is rated by many as belonging to the class of genius; then +the rank and file of mankind uses but a small fraction of its potential +brain power. This fraction has been variously estimated at one fifth or +one half. It seems obvious that great advantages for the extension of +intelligence might arise from the utilization of the unemployed fifty +to eighty per cent. of human power. The large portion of the brain not +used by the majority of mankind introduces the disquieting thought +that the usual way of life is the easiest way. The intelligent way is +laborious and fraught with many trials incident to arduous application. +Brain capacity may be improved only by patient and continuous effort +and by an unremitting submission to diligent self-discipline. The +avoidance of these exactions has made the development of the brain a +slow process in man. It is the general disinclination to depart from +the path of least effort which has held human intelligence at its +average low levels. Many factors have contributed to this attitude. +Not the least among them is what may be called mixed survival. This +is a provision by which not only those thoroughly equipped but those +as thoroughly unfit are presumed to enjoy equal opportunity in the +advantages of life. The unfit depreciate the general average. Their +inclusion creates the level of mediocrity and retards the progress of +the fittest. + +Another fact affords hope for the further development of the unused +fractions of human brain power. It is possible to demonstrate that +certain structural and chemical elements in the brain develop in +relation to the use made of them. This is particularly true of the +insulating substance surrounding nerve fibres. Such fibres serve the +purpose of impulse conduction. Simple and complex associations alike +depend upon them. It has been shown that the simplest of these fibre +connections come into use early in life while the most important +connections appear at later periods. In order to be effective the +connecting fibres must be insulated. The insulating material, a complex +chemical substance, makes its appearance in direct relation to the +different periods of mental development. This insulating substance is +least in amount at birth. It increases noticeably at the end of the +first year at about the time when speech is acquired. It shows marked +additions at the seventh, tenth, and twentieth years. Thereafter +it increases slowly up to the fortieth year. It also manifests the +interesting phenomenon of gradual decrease in the declining years +of the late decades of life. Apparently the mental development of +different life periods requires differing degrees of insulation in the +brain. The functional use of definite areas appears to bear a direct +relation to the degree of insulation. The more areas in use, the more +numerous are the insulated nerve fibres to facilitate proper operation. +The child uses and needs less than the youth, and, in the general +case, the youth less than the adult. The development of the brain thus +appears to be proportional to the use made of it. In this way human +intelligence may be gauged in terms of actual brain structure. In cases +of low intelligence the demands have been relatively small, and large +fractions of brain remain undeveloped because unused. Higher grades of +intelligence require more extensive development because the objectives +of their application are more complex and more exacting. They are the +response to the more extensive utilization of brain power. + +The recognition of this relation between use and structural development +of the brain clearly points the way by which human intelligence may +be extended. This relation has long been understood as a biological +principle. It has been practically applied in the training of +muscular strength and endurance, in the sharpening of the senses, +in the cultivation of the voice. Its practical application to the +development of the brain as a whole has been much less assiduous. Both +in principle and practice this relation of use to structure indicates +possibilities for producing a better human brain. The unused fractions +may accordingly find opportunity for utilization. + +Still another possibility for advancement arises from more adequate +systems of human training. The success with which the brain is used +depends in large part upon its conditioning. Such conditioning is +determined by many factors. In the broadest sense it includes the +influence of physical environment from the earliest moments of life, +the effects of societal habits and ideals both in the family and in +the group, the impress of formal education and educational forces, and +the direction imparted by differing degrees of satisfaction, health, +and disease. If, for example, the objective is accommodation to Arctic +life, the conditioning process differs in many details from that +necessary for adjustment to tropical existence. If the end sought is +success according to European standards, a totally different set of +conditionings is essential to this result. Civilized nations as well +as barbarous tribes may be trained through generations to the pursuits +and practices of warlike aggression. The results of such conditioning +were clearly demonstrated in the Great War. Ultimate adjustments are +thus strongly influenced by the group, the group outlook, the time, +and the place. For this reason every experience in and every contact +with existence assumes high value as a conditioning factor. The entire +span of life, from birth to death, becomes a period of active training +which may be consciously directed. The element of chief importance +in this conscious control is the recognition of the end to which the +training is directed. If the highest qualities of human happiness and +satisfaction are the objectives, every factor which contributes to +the conditioning must be carefully estimated and properly adjusted to +this end. Such certainly is not the objective under the modern cult of +success. + +The earth, which we have made a bone of contention, might, to our +infinite advantage, become the sphere of human content. In order to +determine such a change it is necessary to reëstimate and readjust +every influence capable of conditioning the activities of the brain. +The recognition of the uninterrupted continuity in the conditioning +process and its specific requirements in relation to definite phases of +development is most essential. Influences of the physical environment +from the first moments after birth through all successive periods +demand extensive, renewed attention. In the formation of habits and +ideals, training in the home and in the group reaches down to the roots +of societal life. These phases of brain conditioning are now largely +matters of dogmatic tradition or confused instruction. + +Our present cult of success dominates formal education. The profound, +far-reaching influence of this department of life is exerted through +the most effective agencies for adjustment and readjustment. Education +is charged with the responsibilities of devising the most beneficial +methods for conditioning the brain. It participates in deciding to what +ends such conditioning shall be directed and thus occupies a position +of supreme control over human behaviour. Its supervision embraces and +guides every period of life. Its disciplines have power to shape the +character of human intelligence. Its inspirations are the hope of the +future. Opportunities are even now at hand for it to overcome its +traditional resistances and to open new fields for human satisfaction +and contentment. Greater than the power of armies, more compelling than +the military force of the entire globe, is the peaceful sway which +education may exert in the satisfactory reshaping of existence. + +There should be added to these possibilities of future progress the +fact that man, in spite of his blemishes, his delinquencies, and +failures, is an aspiring and plastic animal. He is not unwilling to +take the form of any mold in which he may be cast. He has been the +victim of many prejudicial molds--clay in the hands of circumstance. +Yet, whatever his form or deformities, he has always aspired to rise +above himself. His aspirations have been sublimated in the heroes he +has made to admire, in the gods he has selected for worship. Unlike +all other animals, he has had the gift of idealization, the power of +projecting far ahead of himself, beyond the limits of his recognized +imperfections, the ideals of what he hoped or craved to be. Even his +societal veneer, his morals, and his manners are products of his +aspirations. His idealizations of existence in poetry and art show how +tenaciously his vision has dwelt on higher things. Recognition of his +own futilities has made him aspire to a future life of purification and +redemption. Yet in this aspiring he manifests a lingering childhood, +which reveals his still plastic state. The hereafter which he has +designed for himself is based on an infantile system of rewards and +penalties. This eventual refuge is an acquisitive immortality born of +self-interest and bred in self-conceit. It bears the taint of ancient +and sordid motives of the race. It has none of the altruism of that +more noble and practical immortality through which earthly life strives +unselfishly to leave a worthy influence for the benefit of those who +later follow the path of human experience. + +In the light of his possibilities man’s further progress seems assured. +Add to these possibilities his remarkable plasticity, his aspiring +spirit, his youthful racial development, and it appears inconceivable +that he should not advance. Science is constantly placing increased +power at his command. While disclosing to him his place in nature, it +is also revealing what still remains to be accomplished in the conquest +of himself. + +Whatever fault may be found with the technique of human living, +the major complaint is directed against the persistence of the old +objectives. Ancient motives and standards are obstacles in the path +of progress. A less complex life is needed--one with new incentives +and different goals. Many are living and have lived this kind of +life. One among these, the Great Galilean, has made it exemplary. As +its influence comes down through the Christian centuries this life +brings increasing conviction that it is the best yet lived. One third +of the globe’s population professes to follow it. As followers they +are frustrated in their purpose by the persistence of more ancient +influences of the past. Yet it cannot be denied that any order of +humanity higher than the present one requires extensive modifications +in our purposes, our desires, our outlook on life, our manner of +self-expression. A long step in this direction will be taken when the +ancient password of the Old Stone Age--_get_, which for thousands of +years has been the mainspring of existence, is gradually subordinated +by the keynote of a New Golden Age--_give_. This solution of the +problem is likely to seem utopian. Long ago we were admonished to +try it. If we have failed we need not altogether despair. The human +brain has overcome other difficulties to which it has been applied. +With all of its possibilities for improvement, it may in time solve +the supremely difficult problem of human nature. Success such as this +depends upon the further development of science--especially that +comprehensive science which will deal with all of the principles +underlying the behaviour of man. + +In all respects it is a task of gigantic proportions to build the world +anew--to readjust, to recivilize ourselves. At the same time it is the +greatest adventure ever conceived by man--to construct his final empire +of world coöperation wherein to know and to control himself. Should +this be deemed worth while, it must be paid for by the intelligent, +unremitting toil necessary to develop the full capacity of our chief +reliance--the human brain. + + +THE END + + + + +TRANSCRIBER’S NOTES + + +Page 8: original spelling of “Poriphara” retained. + +Typos corrected: “in the dog.” to “in the dog,” (page 146); “pryamid” +to “pyramid” (page 166); “preeminent” to “preëminent” (page 272); +“sufficently” to “sufficiently” (page 316). + +Inconsistencies in hyphenation have been left unchanged. + +*** END OF THE PROJECT GUTENBERG EBOOK 78733 *** |