These are the principal bodily characters which the anthropologist uses to distinguish races and by their means to determine the more immediate or remote community of origin of comparable types. Many of these characteristics, as indeed we may already see, are decidedly important in connection with the second problem specified above, for in the case of the flat triangular nose and projecting jaws of a low negroid we may discern clear resemblances to certain features of the apes.
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Long before the doctrine of evolution was understood and adopted, students of the human races had been deeply impressed by their natural resemblances. As early as 1672 Bernier divided human beings according to certain of these fundamental similarities into four groups; namely, the white European, the black African, the yellow Asiatic, and the Laplander. Linnæus, in the eighteenth century, included Homo sapiens in his list of species, recognizing four subspecies in the European, Asiatic, African, and Indian of America. Blumenbach in 1775 added the Malay, thus giving the five types that most of us learned in our school days. But the different varieties of men recognized by these observers were believed to be created in their modern forms and with their present-day characteristics; the common character of skin color exhibited by any group of peoples of a single continent was to them only a convenient label for purposes of description and classification. It was not until years later that fundamental resemblances were recognized as indicating an actual blood relationship of the races displaying them, and therefore of evolution. Since the doctrine of human descent and of the divergence of human races in later evolution has been accepted, those who have attempted to work out fully the complete ancestry of different peoples have found that no single character can be taken by itself, while the various criteria themselves differ in reliability; the color of the skin is not so sure a guide as the character of the hair and skull, wherefore the classifications of recent times, notably those of Huxley and Haeckel, have been based largely upon the latter. The latest systems have been more rigidly scientific and more in accord with the most modern conceptions of organic relationships in general, as evidenced by the thoroughgoing methods of Duckworth in his recent treatise on human classification.
It now remains to present the salient facts regarding the genetic relationships of typical human races, although it is obviously impossible to go into all of the details of the subject. But these are not essential for the main purpose, which is to show that the evolutionary explanation is the only one that is reasonable and self-consistent. Opinions are sometimes widely at variance regarding countless minor points, but no anthropologist of to-day can be anything but an evolutionist, because the main principles upon which the specialists agree fall directly into line with those established elsewhere in zoölogy. It seems best to state these principles without reverting to controversial matters which find their place in the monographs of the experts. Any comprehensive account such as that of Keane, even if it may not give the final word, will be entirely sufficient to demonstrate how fruitful are the methods of evolution when they are employed for the study of human races, and indeed how impossible it is to discuss human histories without finding conclusive evidences of their evolutionary nature.
The facts that are available indicate that the first members of our species evolved in an equatorial continent which is now submerged, and which occupied a position between the present continents of Asia and Africa. From this center hordes of primitive men migrated to distant centers where they differentiated into three primary and distinct groups. The first of these was gradually resolved into the darker-skinned peoples most of whom now live in the continent of Africa, although many dwell also in the islands of the western Pacific Ocean. The second branch divided almost immediately to produce, on the one hand, the Indians of the new world and, on the other, the yellow-skinned inhabitants of Asia and other places. The third branch developed as such in the neighborhood of the Mediterranean Sea, and produced the series of so-called Caucasian peoples, which are by far the most familiar to us and to which most of us belong. But so early did the second branch divide that there are virtually four main divisions of the human species that are to be examined in serial order.
It is best to begin with our own division, because its greater familiarity makes it easier to become acquainted with the methods and results of anthropology, on the basis of facts that we already know. Three subordinate types exist, located primarily in northern, central, and southern Europe respectively, but many other races dwell elsewhere that are assignable to one or another of these subdivisions. In northeastern Europe we find people such as the Norwegians, Swedes, Danes, and north Germans, that average five feet eight inches in height. They have the long, wavy, and soft hair which is a general characteristic of the whole Caucasian group, although its light flaxen color is distinctive. The blue eye and florid complexion accompany the light color of the hair. The skull is of the longer type, the jaws and forehead are straight and square, the nose is large and long without a distinct arch, and the teeth are relatively small. It is not so well known that the Scandinavian type is so closely copied by many people of Asia, such as the western Persians, Afghans, and certain of the Hindus, living in a continent that we are inclined to assign to the Mongol only. In the possession of these characters the Northern Europeans and other races specified display evidences of their common ancestry and evolution quite as conclusively as in the case of the cats discussed in an earlier chapter where the meaning of essential likeness was first demonstrated.
A broad zone may be drawn from Wales, across Europe and Asia, and even to the eastern islands of the South Seas, in which we find peoples that are obviously of Caucasian descent, but they differ from the members of the first group in some details of structure. On the average they are about five feet five or six inches in height, the hair is dark and wavy, but it is not the pencil-like structure of the Mongol. The complexion is pale, the skull is rounder, and the eyes are usually brown in color. These peoples agree also in their volatile temperament and vivacious manner and are thus markedly different from the more stolid northerners. To this minor branch of the Caucasian stock belong the Welsh, most of the French, South Germans and Swiss, Russians and Poles, Armenians, eastern Persians, and finally some of the inhabitants of Polynesia. The last, it is true, form a well-marked group of darker-skinned and taller races, but in spite of the admixture of these and other unusual features, we can still discern the bodily characters that supplement their traditions, telling of an Asian origin, in demonstrating their common ancestry with round-headed Persians and middle Europeans. Below the zone of middle Europe and Asia is another broad region inhabited by the "Mediterranean" type of Caucasian. The Spaniard, Italian, Greek, and Arab are sufficiently familiar to illustrate the distinctive qualities of this subdivision. These people have the smaller stature, dark hair, dark eyes, and paler skin of the middle Europeans, but the skull is of the long instead of the rounded type. A well-marked subordinate group is formed by the so-called Semitic peoples, such as the Arabs and their Hebrew relatives. The Berbers and other North African races possess a darker skin probably because of the admixture of Ethiopian stock, and they, too, are so well characterized that they form a clearly marked outlying group as the so-called Hamites. Passing over into Asia we find relatives of the Mediterranean man in the Dravidas and Todas of India, possibly in the degenerate Veddahs of Ceylon, and finally in the Ainus or "hairy men" of some of the Japanese islands. The last-named people certainly possess some Mongolian features, but these seem to have been added to a more fundamental form of body that is distinctly Caucasian.
All of the races we have mentioned, together with their relatives, may be compared to the leaves borne upon three branches that take their origin from a single limb of the widespread human part of the tree. They cannot be classified in any mode on the basis of their primary and secondary resemblances without employing the treelike plan of arrangement, which to the man of science is a sure indication of their evolutionary relationships.
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The people of the second or Mongolian group agree in certain well-marked characteristics in such a way as to be well separated from the other divisions of mankind; these characteristics we may speak of as constituting a second "theme," of which the various peoples of the group are so many variations. To visualize them we need only to recall the appearance of the Chinaman, perhaps the most familiar example of the entire series. Here the hair is coarse and black, and straight because of its round transverse section; the mustache and beard of the Caucasians are seldom found except in later life; the skin is a fleshy yellow in color; the skull is round, indeed, it is one of the roundest that we know; the jaws are not so straight as in the Caucasian, for the angle at the point of the chin is about sixty-eight degrees. The cheek bones project laterally, with greater or less prominence; the nose is very small, tilted up slightly at the end, and is usually hollowed instead of arched. The eyes are small and black in color, set somewhat obliquely, and the upper lid is drawn down over the eye at its inner corner so as to make the obliquity still more marked. The teeth are larger than those of the Caucasian. Finally, the Mongol is below the average of all men as regards height, being usually about five feet four inches tall.
The original Mongolians probably developed the characteristic features we have just noted in a Central Asiatic region, and then almost immediately they divided into two great groups. Each of these evolved along certain lines of its own, one sweeping northward to develop into what are now called the Northern Mongols, the other working its way eastward and southward to produce the peoples of China proper, Indo-China, and many parts of Malaysia. Considering first the peoples of the Northern Mongolian division, we find in the typical Manchurian what is perhaps the nearest among modern people to the original race. Spreading northward and westward from the middle Asiatic plains, this great wave has produced the nomadic tribes of Siberia, like the Chukchi, the Buryats, and the Yukaghir. The present inhabitants of Turkestan connect those forms which have remained near the original home with the races of Mongolian origin that live farther to the westward, like the Turks of Asia. But the Mongolian tide originally swept much farther to the west, although it was driven back later by conquering Caucasian peoples; and it has left behind such remnants as the Finlander and the Laplander, the Bulgar, and the Magyar. It is evident that these western branches of the Mongol stock are not at all pure in their racial characteristics, for they clearly show the effects of a mixture with alien European peoples. To assign them to the Northern Mongol division means only that their dominant characteristics are mainly those of Mongolian nature. We have referred the Russians to the middle Caucasian division even though the Slav or Tartar infusion is very great, but it does not dominate over the Caucasian peculiarities as it does in the case of the peoples we have mentioned. As regards the remaining types we must add to this brief list the Koreans and the Japanese, the former being far purer in Mongolian nature than the latter people, which has apparently been affected by a Malay influence from the south.
Turning now to the southern Mongol, we find that from their cradle in the Tibetan plateau they too have spread widely, and their descendants have also come to differ in certain respects as they have established themselves in other lands. Most of the present people of Tibet belong to this section; the Gurkhas of Hindustan, the people of Burma proper, of Annam, and Cochin China are close relatives of one another and of the more characteristic Mongolians of China proper who make up the vast bulk of the population. From this stock we may also derive the Malays of Sumatra and Java, of Borneo and Celebes, and the Tagals and Bisayans of the Philippine Islands. Even the Hovars and other tribes of Madagascar may be referred to this division, for although in them the skin has become somewhat darker, we may still discern the characteristics which indicate their common ancestry with the Oceanic Mongols.
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The American Indians taken collectively constitute a group that is well set off from the rest of mankind by such characters as taller stature, small, straight, and black eyes, a large nose that is usually bridged or aquiline, a skull of medium roundness, and the yellow copper color of the skin. The common origin with the Mongols is demonstrated by the straight and long, coarse, black hair and by the absence of a beard; the mustache also is almost always absent.
All of us have seen Indians belonging to the tribes of the plains, which serve as excellent examples of this grand division. Many have also visited the homes of the Pueblo Indians, and have learned how uniform is the physical appearance of the tribes living in various parts of the United States. Indeed throughout all of North America the basic characteristics of Indians prove to be strikingly conservative, although in the Eskimo there are some departures which seem to indicate a closer connection of these peoples with the Mongols, probably as the result of some more recent influx from the neighboring and not very distant region of northeastern Siberia. Extending our survey southward through Central America, the Aztecs and Mayas are found to possess many of the same characters, though in some respects they are transitional to the Caribs of the northern edge of South America and to the Indians of South America. Traveling still farther southward, we meet the very tall Patagonian, still an Indian in essential respects, and finally, the Yahgan and Alacaluf of the Fuegian region, the most degenerate members of the race. The last-mentioned people are dull and brutish and most degraded in all respects, and stand at the lowest end of the red Indian series as regards intellectual ability and cultural attainment.
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We now come to the last of the four great divisions of the human species which includes the races usually spoken of as Africans or Ethiopians. But these races are by no means restricted to the continent of Africa, for quite as typical black types are found in far-distant lands such as Australia and many islands of the Pacific Ocean. The races assigned to this division group themselves about two subordinate types,—the tall negro proper and the shorter or dwarf negrito,—and each of these has representatives both in Africa and in the oceanic territory.
The black slaves of America were all descended from typical negros brought from the western part of Africa, and they provide us with adequate illustrations of Ethiopians as a group. In them the stature is above the average of men in general, specifically about five feet ten inches. The short jet-black hair is strikingly different from the head covering of the other great groups of human races; each individual hair is so flat in cross-section that it curls into a very tight close spiral, and this brings about a frizzly appearance of the whole head covering. There is little or no beard, the skin is soft and velvety and of various shades approaching black in color. The skull is long, the cheek bones are small, but the most distinctive characteristics of the head are found in the apelike ridges over the eyes and in the very broad flat nose which projects only slightly and turns up so that the nostrils open forward to a marked degree, while in the jaws there is an astonishing divergence from the Caucasian condition in the great protrusion which causes the angle at the chin to be about sixty degrees.
The warlike Zulus and other peoples of Southern and Central Africa are perhaps the most characteristic races in this division. Their relatives are found to the northward as far as the Sahara desert, along the southern borders of which they have spread out to the eastward and westward. Fusion with other races has taken place along this border so that many of these northern tribes are much lighter than the Zulus in the color of the skin. But many relatives of the taller African negro are found in other parts of the world, namely in Australia, and in New Hebrides and New Caledonia—islands to the north and east of this continent. The Papuan of New Guinea is a typical negro in all true respects, with strongly marked Ethiopian characteristics, though there are some differences which are transitional to the more aberrant natives of Melanesia, which includes many archipelagos like the Fiji, Bismarck, Marshall, and Solomon islands. Undoubtedly the most degenerate member of the tall negro division is the Australian native, the so-called "blackfellow." The bulbous nose and the well-grown beard mark him off from the typical stock, but his obvious relationship to this is indicated by the low brain capacity, the prominent ridges over the eyes, and the heavy projecting jaws.
Taking up the other division of the so-called Ethiopian race, constituting the Negrito section, we may begin with its Oceanic members. The natives of the Andaman Islands, the Kalangs and the Sakais of Java and neighboring regions, and the Aetas of the Philippine Islands agree in a dwarfed stature of four feet or a little over, in their yellowish brown skin color, a round head, and woolly reddish-brown hair. They, too, possess large ridges over the eyes and extremely prominent jaws, and in these latter characteristics particularly we see evidences of their relationship to the negro. But perhaps the most characteristic pygmies are found in Africa. The little Bushmen and Hottentots are low types of the Negrito stock, and they lead us to the lowest men of all, the Akkas of the West Congo region. It is difficult for us to realize how utterly degenerate and apelike these pygmies are. The jaws are disproportionately large as compared with the cranium or brain-case, and project to a degree which brings the skull very close to that of the higher apes; while in mental respects, in the absence of dwellings, and in many other ways they prove to be the lowest of all mankind,—veritable brutes in form and mode of life.
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Without a full series of photographs before us the foregoing sketch of the various races of men cannot make us fully acquainted with all the strange varieties of the human body, but it will suffice to establish two fundamental results. While all men agree in the possession of certain features which set them apart from other members of the primate order, they differ among themselves in such a way as to fall into four well-marked subdivisions branching out from a common starting-point. Furthermore, in each of these primary groups the subordinate types arrange themselves also in the manner of branches arising from a common limb. This is the relation that we have earlier found to be a universal one throughout the animal kingdom, and science believes that it indicates everywhere an evolutionary history—an actual development along different lines of descent of forms which have a common starting-point and ancestry.
The second principle is perhaps even more significant: when we review the many races from the Caucasian to the dwarf Negrito, we traverse a downward path which will bring us inevitably to the higher apes. In our survey of human races, we have passed from the Caucasian, with the largest brain and cranium and with straight jaws well underneath the brain-case, to the pygmy with a relatively small brain, with huge projecting jaws and with prominent ridges over the eyes; one step more along that path would bring us to the gorilla or the chimpanzee. The array of lower primates, from the lemur to the gorilla, gives a series of forms exhibiting a progressive advance in respect to the size of the brain and cranium, and a gradual retreat of the jaws to a position underneath the cranium; and one step further brings us to man. In a word, these two lines join—in fact, they are directly continuous. There is a far smaller difference between the lowest man and the highest ape than we have been accustomed to suppose.
Thus in general terms, it can justly be said that process of evolution which developed the first man from its ape-man progenitor seems to have continued during subsequent ages. Spreading out in diverging lines of evolutionary descent no less clearly than they have in geographical respects, certain races have far surpassed their fellows of a lower order, which, like the brute pygmy, remain nearer the common structural form from which all men have sprung.
VI
THE MENTAL EVOLUTION OF MAN
The problems dealing with the make-up of the human mind and with the evidences of mental evolution bring the student to matters of more vivid human interest. Mental phenomena are so complex and intricate that it is well-nigh impossible to analyze their history without a knowledge of the principles derived from the broad study of evolution as a general doctrine, where human prejudice is not so large a factor and where his perspective is less affected by the proximity of the observer to his facts. For these and other reasons the foregoing treatment of human evolution has been confined to the purely structural characteristics of man as a species and of human races as so many varieties of this type. When the broad comparative methods of biological science are employed for the elucidation of human anatomical facts, the result in this special case, like that established through the study of the characteristics of living things in general, is the proof that evolution gives the most rational and natural explanation of the observed data. This being true, the naturalist who turns from purely structural matters to human intellect and its history, finds well-tried methods of inquiry already available, and he approaches his further studies with a conviction that evolution, having proved to be universal so far, in all probability will be found equally true in the case of psychological phenomena. This expectation is indeed realized, and the scope of the doctrine is extended over a new field, when the facts of human psychology are treated as materials for impersonal comparative study; and this result is not only useful and valuable in and by itself, but it also provides in the principles of mental evolution the transition to the field of social relations and ethical ideas and ideals which are apparently the unique possessions of men as individuals and as associated groups.
The field of comparative psychology might seem at first sight to be a foreign territory to the average well-informed layman in science, but the contrary is really the case. Every one has thought at one time or another about his own mental make-up, and about the minds of others. No one can watch a child at play with his toys or at work with his schoolbooks without being struck by many evidences of marked differences between the immature and the experienced types of mind. Every one knows also that the mental "scheme of things" is by no means the same for all nations or races of mankind existing to-day, while furthermore the fact is entirely familiar that the intellectual heritage of a present race has changed in the course of previous ages. Therefore in this field as before we need only to amplify our knowledge of such representative psychological facts as these by drawing upon the full stores of the special investigator, in order to learn that human thought, like the human frame, has undergone a natural history of transformation to become what it is and what it was not.
Many who would be ready to accept the evolution of physical characteristics find it impossible to treat the history of human mentality as a subject for dispassionate consideration, because above all else the intellectual powers of mankind seem to be truly distinctive. It is only after constant use of the methods of science that we can bring ourselves to see how closely we resemble lower forms in physical make-up; still greater reluctance must be overcome before we can view our mental processes as counterparts of those of inferior animals, so essential to our very humanity do they seem. But our duty to undertake the task is plain, and its discharge will be greatly facilitated by a clear realization that mental evolution is but a part of human transformation in times past, as the latter is only a small fraction of the universal process of organic evolution in general. While our own nature and inquisitiveness give us so intense an interest in the teachings of science that relate to the constitution and history of human faculty, wherefore these matters gain an undue prominence in perspective, it must never be forgotten that these teachings do not stand by themselves, for they are built upon the sure foundations already laid in physical evolution; and these foundations cannot be disturbed by our failure to use them as a basis when we construct our own conceptions of human intellect and its history.
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Before passing to the systematic review of the facts and principles of comparative psychology which demonstrate evolution, there are certain general aspects of the subject to be considered so as to clear the ground, as it were, for further progress. When the several organic systems of the human body were compared with those of the apes and of lower animals, their evolution was proved as far as the purely physical and material characteristics were concerned. But we know that there is no part of any one of these systems which has not its own particular function, even though this may be a relatively passive one; while furthermore, science does not know of any physiological activity without some organ or tissue or cell as its material basis. Therefore the evolution of an organic system in material respects involves its functional or dynamic evolution as an inseparable correlate; the two proceed in unity, and they cannot be regarded as entirely distinct without violating common-sense.
The fin of a fish is used as an organ of locomotion in water; from some such organ have evolved the walking limbs of amphibia and reptiles, constructed for progression upon land. Among the mammalia the fore limbs have become structurally adapted so as to be such diverse organs of locomotion as the stilt-like leg of a horse, the flipper of a seal, the whale's paddle, and the bat's wing, while among the birds the wing may change into a flipper like that of the penguin, or become reduced to a vestige as in Apteryx. We may focus our attention upon the material likenesses and differences in such a series of locomotory organs, but an inevitable accompaniment of their physical changes in the transformation of species has been an evolution in the functional matter of locomotion. The most complex and differentiated tracts of even the highest animals have evolved from a simple sac like that of a polyp or jellyfish, as we know from the independent testimony of comparative anatomy and embryology; in this case also the evolution of alimentary functions is no less inseparable from the transformations in structural respects. And again, we cannot understand the historical development of vision without taking into account the eyes of various types belonging to lower and higher animals.
So it is with the nervous systems of man and other animals, and with their functions. The nervous system of the human organism comprises identical organs with the same arrangements that are found in other primates and in lower vertebrates as well; the differences in structure are differences in the degree of the complexity of certain parts, notably of the cerebrum. Therefore the evolution of human mentality, which depends upon a human type of brain as a physical basis, is already demonstrated with the proof that the human brain and nervous system have evolved. It is true that an invariable and necessary connection between mind and matter is implied in the foregoing statement, and this is something which demands further consideration at a later point. But just how the human mind is produced by or depends upon the brain, is of far less importance for us at this time than the obvious fact that mental performance requires active nervous tissues. So far investigation has been unable to discover a valid reason for a belief in the existence of mental phenomena, as such, apart from some kind of material basis. And while we may prefer to restrict the use of the word mind to the series of nervous processes going on in the human organ of thought, in so far as these processes are carried on by the peculiar tissues of the nervous system they cannot be finally distinguished from the functional products or accompaniments of the same kind of active tissues and organs in lower creatures. Thus the subject of mental evolution becomes much clarified at the outset by understanding that nervous processes and nervous systems evolve together.
In the direct treatment of the facts and principles of mental evolution we can use exactly the same classification and subdivisions of the materials of study as heretofore, because psychological data are the correlates of material organic systems, and also because the former, being natural phenomena, are subject to the methods of analysis which can be employed for any series of objects that have undergone evolution. Separating the matter of fact from the question as to the method, and recalling the main bodies of evidence as to the reality of evolution, we may establish four sections of the subject before us: these are (1) the anatomy, (2) the embryology, and (3) "palæontology" of mind, and (4) an inquiry into the way nature deals with the psychical characteristics of organisms in accomplishing their evolution. To specify more particularly, it is possible in the first place to compare the activities belonging to the category of mental and nervous operations, displayed by man and other organisms, and the results form the subject of comparative descriptive psychology; the second division, namely, developmental or genetic psychology, deals with the sequence of events in the life of a single individual by which the infantile and adolescent types of mind become adult intellectuality; in the third place, in speaking of the palæontology of mind, the phrase is used to refer to the varied and changing mental abilities of human races in historic and prehistoric times as they may be demonstrated and determined by the evidences of the culture of such earlier epochs. In considering the matter of method, the questions are whether variation, inheritance, and selection are as real in the world of mental phenomena as they are in the material world, and whether the laws are the same or similar in the two cases. We shall learn how the results of such studies prove with convincing clearness, first, that the contents of the individual mind and of the minds of various human races are truly the products of natural evolution, and second, that the human mind differs only in degree from that of lower organisms, and not in kind or fundamental nature.
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When the operations of human mental life are examined, they include what are called processes of reason as apparently distinctive elements. The lower mammalia exhibit a simpler order of "mentality" denoted intelligence, while the nervous processes of still simpler forms are called instinctive and reflex activities. These are the terms of the comparative array of psychology which are to be separately examined and classified, and to be brought into an evolutionary sequence if common-sense directs us to do so.
Let us begin our comparative study with an example of the simplest animals that consist of only a single cell, such as the little protozoon Amoeba. We have become familiar with this organism as one that carries on all of the vital functions within the limits of a single structural unit; it is a mass of protoplasm enclosing a nucleus, and as a biological individual it must perform all of the eight tasks that are essential for life. It does not possess a digestive tract, but it does digest; it does not have breathing organs, but it does respire; and it is particularly noteworthy that it must coordinate the different activities of its parts, and maintain definite relations with the environment, even though its coordination and sensation are not accomplished by any special parts that would deserve the name of elementary nervous organs. Its many activities are simple responses to stimuli that reach it from without, and its reactions to such stimuli are called reflex processes. Should the light become too strong, it will slowly crawl to a shady place; should the water in which it lives become warmer, it responds by displaying greater activity. It exhibits, in a word, the property of irritability—that is, simply the power of receiving and reacting to stimuli; and being only a single cell this property is held in common by all of its parts.
We come next to a simple many-celled animal like the polyp Hydra, or a jellyfish. In such an animal the body is composed of numerous cells which are not all alike either in their make-up or in their functions. Some of them are concerned primarily with digestion, others with protection, while still others are exempt from these tasks and as sense-cells they devote all their energies to the reception of stimuli from without, or, beneath the outer sheet of cells of the two-layered body, they conduct impulses from one part of the animal to another, and thus serve as coordinating members of the community. For the first time, then, a nervous system as such is set apart and specialized to devote itself to the two tasks of sensation and coordination that are performed by nervous systems throughout the entire range of organisms higher in the scale. But the activities of Hydra, like those of Amoeba, are reflex and mechanical,—that is to say, given similar stimuli and similar physiological states of the animal, the reactions will be the same. A little water-crustacean like Daphnia may swim against the tentacles of Hydra; it is stung to death by the minute cell-batteries which the animal possesses, and then in a mechanical way the tentacles transport the food to the mouth, through which it is passed inward to the digestive cavity. There is nothing that can be called "mentality" throughout these processes, but the series of activities is much more complex than in Amoeba because the whole organism is constructed more elaborately, and because the special and peculiar mechanism directing the activities has advanced to a far higher condition.
Passing to the jointed animals like worms and insects, we find nervous mechanisms that are still more intricate, and with their advance in structural respects there is a corresponding and correlated progress in their functions. Because the whole organism has developed more highly differentiated groups of organs to perform the several biological tasks, such as eating and respiring and moving, it is necessary for the nervous structures concerned with the direction of these actions to become more efficient. An earthworm avoids the light of day and digs its burrow and seeks its food by wonderfully coördinated activities of its muscles and other parts, which are controlled by a double chain of ganglia along its ventral side, connected with a similar pair of grouped nerve-cells above the anterior part of the digestive tract. The ganglia of each segment exercise immediate supervision over the structures of their respective territory, while they pass on impulses to other ganglia so that movements involving many segments can be properly adjusted. Everything an earthworm does is controlled by the cells grouped in these ganglia, or scattered along the intervening connecting cords. We speak of its acts as instinctive, employing a term which seems to indicate a different kind of operation carried on by the nervous system, but a moment's thought will show that an instinctive act is simply a complex group of reflex acts. The physical basis and ultimate unit is a cell, and the functional unit is likewise a cell act; therefore the seeming difference proves to be one merely of degree and not of kind. The greater complexity of the worm's nervous system as compared with that of Hydra gives to the whole mechanism a plasticity that diverts the attention from the mechanical nature of the entire instinctive act and of its basic cell elements.
The instinct, like the elementary reflex, is determined by heredity. Because a certain configuration of the cells and fibers making up a nervous system is inherited as well as the characters of the constituent elements themselves, a worm or an insect is enabled to act as it does. A butterfly does not have to learn how to fly, for it flies instinctively. When it emerges from its chrysalis with its complete adult series of wings and muscles, it has also the nervous mechanism by which these parts are mechanically controlled. A ground-wasp deposits its eggs in a small burrow in which it places also a caterpillar or a grasshopper paralyzed by stinging, so that when the larva is hatched from an egg it finds an ample supply of fresh food provided by a complex series of its mother's acts that seem to be directed by conscious maternal solicitude. When the larva passes through the later stages of development and makes its way to the open air as a fully formed adult, it in its turn may go through the same course of action as its parent, but it is clear that it cannot have any remembrance of its mother's work or any personal knowledge of the value of burying its own eggs in a chamber with a living prisoner to serve as food. It was an egg when its parent did these things; as a parent itself it does not remain on watch to see how beneficial or fruitless its acts may be. A mechanism produced by nature's methods, the ground-wasp behaves as it is capable of working with its inherited structure and its inherited instinctive powers of coördination and sensation.
The complex lives of communal insects like ants and bees bring us to the level of mentality where an understanding of causes and effects seems to be the guide for conduct. Nevertheless the facts do not warrant the assumption that reason and intelligence play any part in the mental life of these creatures, as they do in the lives of man and the apes. Because we ourselves can see the utility of the definite and peculiar behavior of the queen and the worker, there is no logical necessity for assuming an identical form of knowledge as a possession of these insects. Many investigators have dealt with these fascinating subjects, and they are almost unanimous in the conclusion that the instinct of an insect is a mechanical and hereditary synthesis of combined reflex acts.
The lower orders of psychological processes play a far larger part in the lives of the higher animals than we are wont to believe. A pointer and sheep dog possess different qualifications in the way of instincts that make them useful to man in different ways. A bulldog or a game-cock does not reason out its course of action during a contest, but like a mechanism when the spring is released, it acts promptly and with effect. A ball flashing past the human eye causes the lids to close unconsciously, and it is not always possible to inhibit this instinctive mechanical act by the exercise of the will. An examination of the workings of the human body reveals manifold activities of an even lower or reflex nature, like the movements of the viscera and the adjustments in respect to the amount of supplies of blood sent to different parts of the body as local needs arise. Directed always by specific portions of the nervous system, such reflex actions play their part in human life without any effort on the part of reason and so-called will, and without coming into consciousness except indirectly and subsequently.
Passing by many interesting members of the psychological series of intergrading forms, we reach the familiar animals like the cat and dog and horse which display what is called intelligence. This is the power to learn by experience, and to improve the quality and promptitude of reactions to stimuli. In certain respects intelligence seems to differ from instinct, inasmuch as it involves a response to stimuli that may be altered and quickened by repeated experience, but in ultimate analysis the two forms of psychological processes are fundamentally alike. A single example chosen from Thorndike's extensive investigation will serve to bring out the primary characteristics of intelligence. A cat was placed in a latticed cage provided with a door that could be opened from within when a catch was pressed down, and meat was put in a dish outside the door where the cat could see it. At first, the animal escaped from the cage by freeing the door during its aimless scrambling about the catch, but as trial after trial was made, the time necessary for the cat to make its way out was shortened, until after seventy-five or one hundred trials, the animal immediately opened the door and seized the food. In mechanical terms, the connection between "scrambling about the door" and "freedom to get the meat" became established by numerous repetitions until the originally disconnected elements were physiologically associated and made inseparable. When animals like horses and seals and dogs are trained for the circus, it is by exactly the same method, for training consists merely in the establishment of a psychological sequence so that the performance of one series of acts leads mechanically to others. Thus we learn that the psychological property called intelligence is the ability to establish wide relations between numerous activities which are themselves of a more or less complex nature; and we find also that because these elements are ultimately nerve-cell and sense-cell reflexes, an intelligent response is quite as machine-like as any and all of its elements. A difference in degree of complexity and extent is the only thing that places intelligence apart from instinct and reflex action, for the units are the same in all cases,—so far as science knows.
The apes are of the greatest value in providing the transition from the grade of intelligence to the human level where reason is found. Whether or not a chimpanzee can reason at all is less important than the fact that its total "mental" powers are lower than those of man, and higher than those of inferior mammalia. Apes are far more susceptible to training than cats and dogs, because their improved nervous mechanism enables them to establish a psychological sequence with greater facility. If we are to judge by the facts at hand, these creatures possess a low order of mentality, like, but by no means equivalent to, that of man.
At the end of the comparative scale, we reach the human mind which is characterized by its ability to perceive and recognize far wider relations than those which are involved in intelligence. Human consciousness is the stream of thoughts and feelings which constitute the immediate contents of mind. In our own case, we know both the activities we perform and some of the internal phenomena with which such activities are connected. Then we are impelled to compare the objective phenomena of action with the behavior of other men and of lower organisms, and if their behavior does not coincide with our own we are justified in believing that its direction lacks some of the elements we know about in our own case. This is the method of comparative psychology, which establishes the conclusion that reason is the more complex term of a series to which reflex action, instinct, and intelligence directly lead.
Were we to study in detail the psychology of adult human beings, we would find only more truly that instinct and intelligence play a large part in our everyday mental life, and more certainly that even the highest reasoning powers we possess are only more complex in nature than the nervous processes of lower mammals and invertebrates. Just as the nervous systems advance in physical or structural respects, so must their activities become more and more complex until the result is human faculty.
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We must now briefly consider what may be called the "comparative anthropology" of mind which deals with the various degrees of mental ability displayed by different human races; this subject follows inevitably upon the comparison of the human mind viewed as a single type with the psychological processes of lower animals. When we reviewed the diverse characteristics of human races—the protrusion of the jaws, greater or lesser stature, and the like—it appeared that so-called "lower" races could be distinguished which differed from the "higher" races in the direction of the apes; the question immediately arises whether similar distinctions and relations are discoverable on the basis of mental traits. But in the present case there are not so many well-substantiated differentia at the disposal of the student, and it does not appear so clearly that the "higher" races are furthest from the lower primates and lower mammalia as regards their mental processes. What facts there are, however, prove to be highly significant, and they materially amplify our conception of human faculty as a product of evolution. The essential point is that the intellectual attainments of various races are by no means the same. The calculus is a mental product of the white race only; gunpowder and printing from movable type were independently invented by the Caucasian and Mongolian races; but the American Indian and the Negro never originated them. Human faculty, to employ the most general term for all that distinguishes man from the brutes, proves to be a very varied thing when we draw comparisons between and among races with independent lines of ancestry and heredity occupying widely separated areas. Should we analyze it, we find it to be composed of three constituents; namely, the physical elements of the brain, the degree to which the observational or perceptual and higher elements cooperate in building up the conceptions peculiar to the type, and the materials with which the physical mechanism deals, in the way of environmental, educational, and social "grist for the mental mill." Many anthropologists accord too great an importance to the third constituent of human faculty, I believe, and they are therefore led to deny that races differ in mental respects to so large a degree as the thoroughgoing evolutionist would contend. They hold that differences in such things as powers of observation are due to training: that, for example, an American Indian or a South Sea Islander sees certain things in his environment more quickly than a white man only because these are the things which the experiences of his earlier life have accustomed him to look for and to find. This may be granted, and it may also be admitted that children of so-called "lower" races can be educated side by side with the youth of white races without noticeably falling behind, up to a certain point when, at the age of adolescence, in the classic case of the Australian natives, other factors prove to be obstacles to further progress. We must also recognize that the character of the environment of a race determines to a large extent the mode of life of the people; a forest-dwelling Indian of the interior is a hunter as well as a warrior, while a South Sea Islander is a navigator and a fisherman.
But the fact remains that the inhabitants of similar countries have reached markedly different grades of intellectual and cultural life. Anglo-Saxon dominance must be referred ultimately to Anglo-Saxon heredity and not to the peculiarities of the land. Although adaptation is no less necessary for men as individuals and as social groups than it is for all other living things, I believe that it is to diversity in constitutional endowments, however these may have arisen, that we must attribute the superiority of some races over others. The question is not whether a savage race can or cannot adopt the higher conceptions of a civilized people; the fact is that they have not actually become civilized by themselves. Thus, while evolution in mental respects has not resulted in the loss of plasticity in the case of the brain and the nervous system as a whole, wherefore the activities of these organs still remain capable of individual and racial modifications that are impossible in the case of the skeleton and in the color and shape of the eye, it remains true that races do differ intellectually, and that their differences are marks of a mental evolution quite as definite as their physical natural histories of change.
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In my own view the strongest and most impressive evidence bearing upon the great problem before us is provided by the series of transformations by which the human intellect develops during an individual life. Mind has an embryology no less significant than that of the skull or of any other element of the body; and its investigation leads to the evolutionary interpretation quite as surely as the study of the various grades of adult psychology constituting the anatomical sequence, which we have reviewed previously. When in the earlier part of the book we dealt with embryology in general, we learned how the changes which take place when an organism develops from an egg demonstrate the actuality of true organic transformation without the necessity of concluding or inferring that this process might occur. It is not superfluous to insist again that the essential fact in evolution is the alteration of one organic characteristic into another type; must we not recognize at the very outset that mental transformation is as real as physical development?
In the first instance we might concern ourselves with the physical basis of mind and its history. In the earliest stages of human embryology no nervous system whatsoever is present, and it is unreasonable to suppose that there is anything going on which corresponds to human thought. A little later a cellular tube is established as a primitive nerve axis, which at first is nearly uniform throughout its entire length and displays no differentiation into brain and spinal cord. Before long an enlargement of the anterior end expands and develops into a primitive three-parted brain. It is not yet a real brain, however, and it is entirely incapable of functioning in such a way as to justify the use of the word mental for the results of its operations. We know that it is only in the cerebral hemisphere of the adult brain that the processes of true human consciousness go on. But it is not until long after the three-parted stage that the cerebral hemispheres make their appearance therefore we cannot speak of mind as present when the cell and tissue basis of mind is not present. When, now, the cerebral hemispheres do appear, they are small bean-shaped structures no larger relatively than those of a fish. Later they enlarge so as to attain the relative size of the cerebral hemispheres of an amphibian, and still later they are like those of a reptilian brain. Continuing to enlarge, they begin to fold so that the total surface is increased without very much addition to their bulk. At this time the cerebral hemispheres of the brain of the human embryo are like those of an adult cat or dog. The process of general enlargement and of progressive convolution are continued, and stages are reached and passed which correspond with the monkey and ape conditions.
Nothing in human development is more impressive than the origin of the cerebrum and its development by passing through successive stages which are counterparts in the main of the adult brains of other and lower animals. The alteration of a tissue-mechanism constructed in one way into a tissue-mechanism of a more complex nature, provides the most conclusive evidence of the reality of brain evolution, because the process of transformation actually takes place.
But in the present connection we are more interested in the dynamic or functional aspects of mental evolution, which it must be remembered are inseparably bound up with the physical structures and their modifications. After a human infant is born its activities are reflex and mechanical like those of the adult members of lower groups. As it grows it performs instinctive acts because its inherited nervous system operates in the purely mechanical manner of a lower mammal's nervous system. For these reasons an eminent psychologist has said that the mental ability of an infant six months old is about that of a well-bred fox terrier. The same infant at nine months displays an intelligence of a higher order equal to that of a well-trained chimpanzee; it has become what it was not, and in so far it has truly evolved in mental respects. At two years of age the child is incapable of solving problems of the calculus, for its reasoning powers are elementary and restricted, but these same powers change and intensify so as to render the older mind quite capable of grasping the highest of human conceptions and ideas. In my judgment the unbroken transformation of a child's mind that exhibits only instinct and intelligence into an adult's mind with its power of reasoning, is far more conclusive as proof of mental evolution than the inference drawn from the comparisons we have made above of the adult psychological phenomena of man, ape, cat, and fish. It is surely natural for such mental transformations to take place, for they do take place in the vast majority of human beings; when they do not, in cases where the brain fails to mature, we speak of unnatural or diseased minds.
The third division of our evidence relating to mental evolution constitutes what we have called the palæontology of mind. By this term we mean the study of human minds of the past as we may know them through the many varied relics and documents which indicate their characters. It is only too obvious to every one that human knowledge has advanced in the course of time and that every department of human thought and mental activity has participated in this progress. No one would have the temerity to assert that we know nothing more than our ancestors of 5000 or even 1000 years ago. Our common-sense teaches us even before the man of science produces the full body of evidence at his disposal that human faculties have evolved. With regard to reasoning powers, which form one of the four distinguishing characteristics of the human species as contrasted with other animals, the case has already been reviewed, and we now turn to speech and language and other departments of human mentality. When we compare the attainments of present day men with the abilities and ideas of their ancestors we will do for mental phenomena precisely what was done when we compared the skeletons of modern animals with those of creatures belonging to bygone geological ages; in this reason is found the justification for the phrase employed in the present connection.
Written history furnishes a wealth of material for interpreting the mental conditions of ancient peoples, but beside documentary evidence the anthropologist learns to use inscriptions of prehistoric times, the primitive graphic representations on tombs and monuments, and even the characteristics of crude implements like axes and arrow-heads. The layman finds it difficult at first to regard such relics as indications of the mental stature of the people who made and possessed them; but a little thought will show that a man who used a rough stone ax in the time of the ancient Celts could not possibly have had a mind which included the conception of a finished iron tool or modern mechanism. So in all departments of human culture, the evolution of material objects may be justly employed in interpreting and estimating the mental abilities of ancient peoples.
Language is undoubtedly the most important single intellectual possession of mankind, for it constitutes, as it were, the very framework of social organization. Without a ready means of communication the myriad human units who perform the varied tasks necessary for the economic well-being of a body-politic would be unable to coordinate their manifold activities with success, and the structure of civilized societies at least would collapse. It needs no legend of a Tower of Babel to make this plain. So fundamental is this truth that although we may not have recognized it explicitly, we unconsciously form the belief that speech and language are exclusive properties of the human species, and even more characteristic of man alone than the power of reason itself. While organized language is clearly something that as such we do not share with the lower animals, nevertheless we cannot regard the communication of ideas or states of feeling by sound as an exclusive property of mankind. All are familiar with the difference between the whine and the bark of a dog and with the widely different feelings that are expressed by these contrasted sounds. And we know too that dogs can understand what many of their master's words signify, as when a shepherd gives directions to his collie. We could even go further down in the scale and find in the shrill chirping of the katydid at the mating season a still more elementary combination of significant instinctive sound elements. To the comparative student the speech of man differs from these lower modes of communication only in its greater complexity, and in its employment of more numerous and varied sounds,—in a word, only in the higher degree of its evolution. And it is even more evident that the diverse forms of speech employed by various races have gradually grown to be what they now are.
At the outset it is well to distinguish between writing, as the conventional mode of symbolizing words, and spoken language itself; the two have been more independent in their evolution than we may be wont to believe. Speech came first in historical development, just as a child now learns to talk before it can understand and use printed or written letters. Furthermore, many races still exist who have a well-developed form of language without any concrete way of recording it. It is true, of course, that back of the conventions of speech and writing are the ideas themselves that find expression in the one way or the other, or even by the still more primitive use of signs and gestures. But it is not with these ultimate elements of thought that we are now concerned; our task is to learn, first, what evidences are discoverable which show that the property of human language in general has originated by evolution, and then, in the second place, to perceive how this development proves an evolution of one group of ultimate ideas, namely, human concepts of the modal value of words and symbols as expressions of ideas themselves.
A simple common-sense treatment of obvious facts will greatly facilitate our progress. We know very well that the English we speak to-day differs in many ways from the language of Elizabethan times, and that the former is a direct descendant of the other. The latter, in turn, was a product of Norman French and Anglo-Saxon,—a combination of certain elements of both, but identical with neither of its immediate parents. The Saxon tongue itself has a history that leads back to King Alfred's time and earlier. Thus we are already aware of the fact that our speech has truly evolved, like the physical structure of the men who employ it; and we know, too, how readily new words are adopted into current English, like tabu from Polynesia, or garage from the French, showing that language is even now in process of evolution.
The sounds that make up spoken words can be resolved into a single element with its modifications; this basic element is the brute-like call or shout made with the mouth and throat opened wide—a sound we may have heard uttered by men under the stress of pain or terror. All of the various vowels are simply modifications of this element by altering the shape of the mouth cavity and orifice, while the consonants are produced by interrupting the sound-waves with the palate or lips or tongue. Like the cell as a unit of structure throughout the organic world, this elemental utterance proves to be the basic unit of all human languages, which vary so widely among races of to-day no less than they have in the history of any single people.
One of the first steps in the making of spoken words was taken by human beings when they imitated the calls or other sounds produced by living things, and tacitly agreed to recognize the imitation as a symbol of the creature making it. Thus the names for the cuckoo and the crow in many languages besides our own are simply copies of the calls uttered by these birds; a Tahitian calls a cat mimi; the name for a snake almost invariably includes the hissing attributed to that creature. After a time words which were at first simply imitations and which referred only to the things that made these sounds came to refer to certain qualities of the things imitated, so that the naming of other than natural objects, such as qualities, began, leading ultimately to the use of words for qualities belonging to many and different objects in the way of abstractions.
Much light upon the evolution of language is obtained when we treat the speech of various races as we did the skeletal structures of cats and seals and whales. When we compare the Italian, Spanish, Portuguese, and French languages, they reveal the same general structure in thousands of their words,—a common basis which in these cases is due to their derivation from the same ancestor, the Latin tongue. The Latin word for star is stella, and the Italian word of to-day is an identical and unchanged descendant, like a persistent type of shark which lives now in practically the same form as did its ancestor in the coal ages. The Spanish word is estrella, a modified derivative, but still one that bears in its structure the marks of its Latin origin; the French word étoile is a still more altered product of word evolution. Even in the German stern, Norse stjern, Danish starn, and English star we may recognize mutual affinities and common ancestral structure. Choosing illustrations from a different group, the Hebrew salutation "Peace be with you," Shalom lachem, proves to be a blood cousin of the Arabic Salaam alaikum, indicating the common ancestry of these diverse languages. Among Polynesian peoples the Tahitian calls a house a fare, the Maori of New Zealand uses whare, while the Hawaiian employs the word hale, and the Samoan, fale. Whenever we classify and compare human languages, we find similar consistent anatomical evidences of their relationships and evolution. We can even discern counterparts of the vestigial structures like the rudimentary limbs of whales. In the English word night certain letters do not function vocally, though in the German counterpart Nacht their correspondents still play a part. In the word dough as correctly pronounced the final letters are similarly vestigial, although in the phonetic relative tough they are still sounded.
The evolution of the art of writing appears with equal clearness when we compare the texts of modern peoples with inscriptions found on ancient temples and monuments and tablets. Even races of the present day employ methods of communicating ideas by writing symbols that are counterparts of the earliest stages in the historic development of writing. An Eskimo describes the events of a journey by a series of little pictures representing himself in the act of doing various things. A simple outline of a man with one arm pointing to the body and the other pointing away indicates "I go." A circle denotes the island to which he goes. He sleeps there one night, and he tells this by drawing a figure with one hand over the eyes, indicating sleep, while the other hand has one finger upraised to specify a single night. The next day he goes further and he employs the first figure again. A second island is indicated, in this case with a dot in the center of the circle to show a house in which he sleeps two nights, as his figure with closed eyes and two fingers uplifted shows. He hunts the walrus, an outline of which is given alongside of his figure waving a spear in one hand; likewise he hunts with a bow and arrow, which is demonstrated by the same method. A rude drawing representing a boat with two upright lines for himself and another man with paddles in their hands gives a further account of his journey, and the final figure is the circle denoting the original island to which he returns.
Pictography, as this method of communicating ideas is called, is often highly developed among the American Indians. For example, a petition from a tribe of Chippewa Indians to the President of the United States asking for the possession of certain lakes near their reservation is a series of pictures of the sacred animals or "totems" which represent the several subtribes. Lines run from the hearts of the totem animals to the heart of the chief totem, while similar lines run from the eyes of the subsidiary totems to the eyes of the chief, and these indicate that all of the subtribes feel the same way about the matter and view it alike,—the sentiment is unanimous. From the chief totem run out two lines, one going to the picture of the desired object, while the other goes to the President, conveying the petition. Thus pictography, a method of writing that belongs to the childhood of races, may be made to communicate ideas of a strikingly complex nature.
The ancient and modern inscriptions of Asia, from the Red Sea to China, present many significant stages in the development of picture-writing. In earliest ages the men of Asia made actual drawings of particular objects, such as the sun, trees, and human figures; subsequently these became conventionalized to a certain degree, but even as late as 3000 B.C. the Akkadian script was still largely pictographic. From it originated the knife-point writing of Babylonian and Chaldean clay tablets, while among the peoples of Eastern Asia, who continued to draw their symbols, the transition to conventionalized pictures such as those made by the Chinaman was slower and less drastic.
In another line of evolution, the hieroglyphics of Egyptian tombs and monuments illustrate a most interesting intermediate condition of development. These inscriptions have been deciphered only since the discovery of the famous Rosetta stone-fragment, which bears portions of three identical texts written in hieroglyphics, in Greek, and in another series of symbols. The Egyptian used more or less formalized characters to represent certain sounds, while in addition to the group of such characters combined to make a word, the scribe drew a supplementary picture of the thing or act signified. For instance, xeftu means enemies, but the Egyptian graver added a picture of a kneeling bowman to avoid any possible misapprehension as to his meaning. The symbols denoting "to walk" are followed by a pair of legs; the setting sun is described not only by a word but also by its outline as it lies on the horizon. Here again one is struck by the similarity between a stage in the historic development of racial characteristics and a method employed at the present time to teach the immature minds of children that certain letters represent a particular object; in a kindergarten primer the sentence "see the rat and the cat" is accompanied by pictures of the animals specified, in true hieroglyphic simplicity.
Just as the child's mind develops so that the aid of the picture can be dispensed with, and the symbolic characters can be used in increasingly complex ways, in like manner the minds of men living in successive centuries have evolved. While an evolution of human conceptual processes in general is not necessarily implied by the evolution of the forms of written language, the former process is in part demonstrated by the latter in so far as the change from the writing of pictures to the use of conventional symbols involves an advance in human ideas of the interpretation and value of the symbols in question. A man of ancient times drew a tree to represent his conception of this object; in the writing of English we now use four letters to stand for the same object, and none of these symbols is in any way a replica of the tree. It is certainly obvious that some change in the mental association of symbol and object has been brought about, and to this extent there has been mental evolution.
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Passing now to other departments of human culture, we must deal in the next place with the basic "arts of life"; that is, the modes of conducting the necessary activities of every day. All men of all times, be they civilized or savage, are impelled like the brutes by their biological nature to seek food and to repel their foes. The rough stone club and ax were fashioned by the first savage men, when diminishing physical prowess placed them at a disadvantage in the competition with stronger animals. Smoother and more efficient weapons were made by the hordes of their more advanced descendants, some of whom remained in the mental and cultural condition of the stone age like the Fuegian, until the white travelers of recent centuries brought them newer ideas and implements. In Europe and elsewhere the period of stone gave place to the bronze and iron ages, and throughout the changing years human inventiveness improved the missile and weapon to become the bow and arrow of medieval civilization and recent African savagery. The artillery and shells of modern warfare are their still more highly evolved descendants.
So it is with the dwellings of men, and the significance of the changes displayed by such things. The cave was a natural shelter for primitive man as well as for the wolf, and it is still used by men to-day. Where it did not exist, a leafy screen of branches served in its stead; even now there are human beings, like the African pygmy and the Indian of Brazil, who are little beyond the orang-outang as regards the character of the shelter they construct out of vegetation. From such crude beginnings, on a par with the lairs and nests of lower animals, have evolved the grass huts of the Zulu, the bamboo dwelling of the Malay, the igloo of the Arctic tribes, and the mud house of the desert Indians. The modern palace and apartment are merely more complex and more elaborate in material and architectural plan, when compared with their primitive antecedents.
Baskets, clay vessels, and other household articles testify in the same way to an evolution of the mental views of the people making them. The means of transportation are even more demonstrative. The wagon of the early Briton was like a rough ox-cart of the present day, evolved from the simple sledge as a beginning. In its turn it has served as a prototype for all the conveyances on wheels such as the stage-coach and the modern Pullman. The history of locomotives, employed in the first chapter to develop a clear conception of what evolution means, takes its place here as a demonstration of the way human ideas about traction have themselves evolved so as to render the construction of such mechanisms possible.
The primitive savage swimming in the sea found that a floating log supported his weight as he rested from his efforts. By the strokes of his arms or of a club in his hand, he could propel this log in a desired direction; thus the dugout canoe arose, to be steadied by the outrigger as the savage enlarged his experience. A cloth held aloft aided his progress down or across the wind, and it became an integral element of the sailing craft, which evolved through the stages of the galley and caravel to the schooner and frigate of modern times. When the steam-engine was invented and incorporated in the boat, a new line of evolution was initiated, leading from the "Clermont" to the "Lusitania" and the battleship.
The history of clothing begins with the employment of an animal's hide or a branch of leaves to protect the body from the sun's heat or the cold winds. Other early beginnings of the more elaborate decorative clothing are discerned by anthropologists in the scars made upon the arms and breast as in the case of the Australian black man, and in the figured patterns of tattooing, so remarkably developed by the natives in the islands of the South Pacific Ocean. A visit to a gallery of ancient and medieval paintings clearly shows that the conventional modes of clothing the human body have changed from century to century, while it is equally plain that they alter even from year to year of the present time, according to the vagaries of fashion.
A brief review of the "arts of pleasure," including music and sculpture and painting, demonstrates their evolution also. The earliest cavemen of Europe left crude drawings of reindeer and bears and wild oxen scratched upon bits of ivory or upon the stone walls of their shelters; the painting and sculpture of early historic Europe were more advanced, but they were far from being what Greece and Rome produced in later centuries. Indeed, the evolution of Greek sculpture carried this higher art to a point that is generally conceded to be far beyond that attained by even our modern sculptors, just as flying reptiles of the Chalk Age developed wings and learned to fly long before birds and bats came into existence.
In the field of music, the earliest stages can be surmised only by a study of the actual songs and instruments of primitive peoples now living in wild places. No doubt the song began as a recitation by a savage of the events of a battle or a journey in which he had participated. In giving such a description he lives his battles again, and his simulated moods and passions alter his voice so that the spoken history becomes a chant. From this to the choral and oratorio is not very far.
Musical instruments seem to have had a multiple origin. The ram's horn of the early Briton and the perforated conch-shell of the South Sea Islander are natural trumpets; when they were copied in brass and other metals they evolved rapidly to become the varied wind instruments typified to-day by the cornet and the tuba. In the same way the reed of the Greek shepherd is the ancestor of the flute and clarionet. Stringed instruments like the guitar, zither, and violin form another class which begins with the bow and its twanging string. The power of the note was intensified by holding a gourd against the bow to serve as a resonance-chamber. When the musician of early times enlarged this chamber, moved it to the end of the bow, and multiplied the strings, he constructed the cithara of antiquity,—the ancestor of a host of modern types, from the harp to the bass-viol and mandolin.
The dance and the drama find their beginnings in the simple reënactment of an actual series of events. Among Polynesians of to-day the dances still retain the rhythmic beat of the war-tread measure, and many of the motions of the arms are more or less conventionalized imitations of the act of striking with a club, or hurling a spear, and other acts. To such elements many other things have been added, but the fact remains that our own formal dances, as well as the sun-dance of the Indian and the mad whirl of the Dervish, are modern products which have truly evolved.
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When we turn to science and philosophy and other intellectual attainments of modern civilized peoples, it is easier to see how evolution has been accomplished, because we possess a wealth of written literature which explains the way that human ideas have changed from century to century. In these cases there can be no question that such evidences provide accurate instruments for estimating the mental abilities of the writers who produced them. We shall take up the higher conceptions of mankind at a later juncture, so at this point we need only to note that even these mental possessions, like household culture and even the physical structures of a human body, have changed and differentiated to become the widely different interpretations of the world and supernature that are held by the civilized, barbarous, and savage races of to-day.