Creation by Evolution/The Human Side of Apes

by Samuel Jackson Holmes

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THE HUMAN SIDE OF APES

By Samuel Jackson Holmes

Professor of Zoölogy in the University of California

For some peculiar reason the animal kingdom includes several kinds of creatures that are remarkably like us in a great many ways. Everyone has noticed the amusing resemblances between apes and men, but few are aware of the numerous and close similarities between them that are revealed by a thorough comparative study. Bone for bone, muscle for muscle, nerve for nerve, we are remarkably close counterparts of our anthropoid relatives. Even in the structure of the brain, which is, perhaps, our most distinctive anatomical peculiarity, there is, as Prof. G. Elliot Smith has remarked, no essential difference, except in degree of development, between ape and man. To be sure, we have a much larger brain, and the so-called association areas are more extensively developed, but in brain structure we differ less from the higher apes than these differ from the lower members of the monkey tribe.

Now mental development and brain development are closely tied together. We stand far above the apes in the development of our minds, and no one is wise enough to gauge the degree of our mental superiority from a study of the structure of the brain. A comparative study of brains, however, would lead us to infer that the ape stands nearer than any other animal to man in mental endowment. And this inference is abundantly justified. Nevertheless, the gap between ape and man is wide. Mr. Darwin, with his well-known candor in giving die fullest weight to objections against his theory, described it as “enormous,” yet in his Descent of Man he endeavors to show that the differences in mentality between man and the higher mammals are not fundamental. Like the mental differences between human beings, which are also enormous, they are differences of degree and not of kind. Consequently we may readily conceive that the human mind may have arisen by an orderly process of development from a mind of lower order.

We are not obliged, however, to regard the evolutionary origin of the human mind as merely a plausible possibility. The evidence for its evolution is much the same as the evidence for the evolution of the body. Resemblance in fundamental features of structure and in method of individual development is justifiably regarded as a strong indication of a common descent. When we compare man with a chimpanzee and note the same form of the external ear, the same rudimentary ear muscles, the same slope of the hairs on the arms and legs, and countless other similarities, even in little useless features of structure, we find the only reasonable explanation of these similarities in the conclusion that they are inherited from some common ancestor.

The same argument applies to the mind, though minds are not so well suited for detailed comparison as bodies. We think that we know something about the human mind, but most of our knowledge lacks the accuracy and precision of the subject matter of our big books on anatomy and physiology. Our knowledge of the ape mind is much less complete. Until recently no one had ever made a really systematic study of the intelligence of the higher apes. Mr. Darwin did his best to bring together the available information on the subject when he wrote his Descent of Man. He had to content himself with the scattered and often rather casual observations of many naturalists. He collected several anecdotes that show the intelligence of apes, their power of imitation, their strong parental affection, their mutual sympathy, their grief over the loss of their young, and their services to one another in times of danger or distress. He showed that the apes share with us all the common basic emotions and that they express their emotions by much the same bodily signs. No one can read Darwin’s book on The Expression of the Emotions in Man and Animals without experiencing a sense of the fundamental kinship of the human and the animal mind and of the likeness in their expression of the emotions. Anger, fear, affection, astonishment, grief, pride, disappointment, and disgust are expressed in much the same way, not only by all the varied races of mankind but by the apes and monkeys. The language of the emotions is a universal mode of communication. The frown has the same meaning in man and apes and is caused by the contraction of the same muscles. The broad similarity in emotional life and in its expression that we share with our simian relatives is as strong an evidence of common origin as the similarity in the form of the skeleton or of the brain.

We now know considerably more of the mental life of apes than was known in the time of Darwin. We are getting better acquainted with our simian cousins, and our more intimate acquaintance has led us to a more generous appreciation of their mental qualities. Many people habitually think of animals as prompted only by feelings that correspond to the lower passions of our own nature. The terms bestiality, animality, and brutality are terms of reproach. The words “ape” and “tiger” are synonyms of ruthless ferocity, the antithesis of everything we regard as worthy in human character. Many are doubtless prejudiced against the doctrine of evolution because they feel that the foundations of morality would be undermined if the conviction becomes general that human beings were derived from animal ancestors. They do not sufficiently realize that the good as well as the evil qualities and impulses of human nature have their counterparts in the animal world. Both men and animals are occupied chiefly in the work of maintaining and perpetuating life. This work involves, in animals and man alike, a due adjustment of efforts to promote individual welfare and the welfare of others of the same species. Most animals pay little heed to the needs of creatures outside their own family or social group. Human beings do likewise. We think little of exterminating animals to satisfy our own needs, or even for mere sport; but we picture the gorilla as a horrible and dangerous creature if he can be provoked into making an attack upon a human being. But why should a man be anything more to a gorilla than a gorilla is to a man? To his own associates this commonly misrepresented animal is a kindly creature having a creditable endowment of domestic and social virtues. So is the man-eating tiger and the prowling wolf. Toward her little group of playful cubs the lioness is an indulgent and self-sacrificing parent, ready to incur any danger to protect her own kind. From her viewpoint man is just so much potential meat for the support of herself and the offspring of her body. The lioness is a beast of prey and a natural enemy of the human race because the evolutionary process, or the Lord, or perhaps both, made her in that particular fashion. Man in turn regards the lioness as a dangerous creature—a creature to be ruthlessly exterminated to insure his own safety.

After all, man's superiority to the lower animals is due

Fig. 1.—Parental love—the gentle yet mighty power that protects and preserves the higher types of life.

primarily to his much finer intellect and to the greater variety and delicacy of his emotions and sentiments. Probably no animal can appreciate the beauty of a sunset or the charm of an attractive landscape. If we can rightly boast of any moral superiority over our less favored animal associates it is not because we are more devoted to our own kind or follow more faithfully the standards of our own particular group; it is because we are consciously moral and are able to make moral judgments and talk about right and wrong; and we can do these things simply because we have much better minds and a richer emotional life than our animal progenitors.

The fear that the foundations of morality would be undermined if it were proved that we are derived from an animal ancestry is eminently absurd. The foundations of moral life lie deeply rooted in the domestic and social instincts, which form the mainsprings of action in animals and men alike. We do not speak of sympathy, mutual helpfulness, or parental love (Fig. 1) as parts of our so-called “animal nature,” although in consistency we should do so, for these traits are as much a part of the nature of animals as ferocity or greed. It is traits such as affection, sympathy, and group loyalty that constitute the basis of our moral impulses and sentiments. Our social and altruistic impulses are no less worthy of esteem if they are shared by less highly developed creatures than ourselves. Like the lower animals, we are in general sympathetic and helpful to our own kind. To our enemies and the enemies of our country we are hostile, and often cruel. All this is human nature. It is also animal nature. In man and animals love and antipathy, courage and cowardice, self-sacrifice and selfishness, loyalty and deception, play much the same part in determining behavior. We play the game of life less simply and crudely than the animals, but our fundamental interests in life are much the same.

In order to gain a clearer appreciation of this general fact let us consider briefly some of the mental and emotional characteristics of our next of kin in the animal world. As to keenness and vision, acuteness of hearing, and other modes of sense perception, man cannot claim any superiority over his ape-like relatives. Turning next to beings of a somewhat higher mental level, such as the apes and monkeys, we find in them a facility for making judgments in difficult situations which is often surprising. For some months I studied the behavior of a small bonnet monkey, Pithicus sinicus, whose intellectual capacities I attempted to gauge by a series of experiments. Lizzie’s level of intelligence was considerably below that of the chimpanzee. Although curious and given to examining all sorts of objects and, whenever possible, pulling them to pieces, her attention could be focussed on any one subject for only a very short time. After she had become quite tame and would perch contentedly on my shoulder, she manifested an unconquerable dread of being seized or taken unawares. Any unusual occurrence would inspire her with instant alarm. Always watchful, she was remarkably resourceful in devising means of escape. She frequently surprised me by getting out through a half-open door which I thought was adequately guarded, and she skilfully obtained many peanuts and apples that I had not intended to give her until she had solved a particular problem. In forming good, practical judgments about means of escape, in stealthily getting food, and in making manoeuvers that involved a rapid analysis of a situation and an appropriate course of action Lizzie showed aptitude of no mean order.

Nothing in Lizzie’s behaviour, however, indicated a close approach to deliberate and formal reasoning; yet her mental adjustments to complex and varying situations were far beyond the capacity of the lower mammals. For life in a tropical forest, where she had to be ever watchful, active, and resourceful, she was an admirably adapted piece of animal mechanism, but her attempts to solve problems requiring deliberation or reflection showed that she was not equal to such tasks. When an apple was placed on a small piece of board outside her cage, she first tried to reach the apple directly, but failing in this she seized the edge of the board and with some difficulty drew it toward her and obtained the prize. When I drove a nail in the board to serve as a sort of handle she reached directly for the nail, drew in the board, and seized the apple. I then substituted a longer board, on which the apple was too far out to be reached even when the near end was pulled against the cage. Lizzie then first pulled the board in by the nail, then drew it sidewise until the apple was sufficiently near to be seized. The appropriate acts were done at the first trial, apparently as a result of inspecting the situation and judging what must be done to get the food. When an apple was placed not on the board but near it, Lizzie drew the board in repeatedly and seemed disappointed because the apple did not come also. She could clearly see that the apple was not on the board, but she did not perceive the futility of her usual performance. When given a nut inside a Mason jar, with the cover screwed on, she would bite and work at the cover, turning it this way and that until it finally came loose. Even after making numerous trials she never learned that the top could be unscrewed by continuously turning it in one direction. When food was placed in a box having a lid fastened by a button or a hook, she could open the box only by working at the fastenings with her hands and teeth until the lid happened to come open. She never clearly perceived why a button or a hook kept her from opening the box. An animal of higher intelligence would have comprehended the cause of the difficulty and performed the appropriate act without wasting so much time and effort in random biting and clawing. Lizzie was very impatient to obtain her objectives. If she could not see quickly and intuitively what course should be followed, she did not spend time in devising new methods of attack. She seemed quite incapable of exercising what we might call conscious deliberation over means of attaining ends.

I have dwelt upon Lizzie's intellectual aptitudes and limitations because they indicate a stage of mental development that is in many respects intermediate between what is found in ordinary mammals and the higher type of mentality possessed by the anthropoid apes. The recent studies of Köhler and Yerkes have added much to our knowledge of the ape mind. These studies had the great merit, as compared with older observations, of putting the animals through experimental tests in order to ascertain the character and extent of their intellectual powers. It has been shown quite clearly that the apes employ means to ends in a way that indicates a faculty of inferring what will happen if the proper conditions are fulfilled. In several experiments performed by Köhler with chimpanzees a piece of fruit was suspended beyond the reach of the animals (Fig. 2). When given boxes to mount upon, the apes quickly learned to pull them into position and climb upon them to reach the fruit. After one of the chimpanzees. Sultan, had learned to use the box the fruit was suspended still higher and two boxes were placed at his disposal some distance away from the objective. His behavior under these conditions was as follows: "Sultan drags the bigger of the two boxes towards the

Fig. 2.—A chimpanzee piling up boxes in order to reach a suspended banana (just out of sight in the illustration).

From Köhler’s The Mentality of Apes. (By permission of Harcourt, Brace & Company, New York.)

objective, puts it just underneath, gets up on it, and looking upward, makes ready to jump, but does not jump; gets down, seizes the other box, and, pulling it behind him, gallops about the room, making his usual noise, kicking against the walls and showing his uneasiness in every other possible way. He certainly did not seize the second box to put it on the first; it merely helps him to give vent to his temper. But all of a sudden his behavior changes completely; he stops making a noise, pulls his box from a distance right up to the other one, and stands it upright on it. He mounts the somewhat shaky structure, several times gets ready to jump, but again does not jump; the objective is still too high for this bad jumper. But he has achieved his task."

After having used two boxes Sultan and some of the other chimpanzees would pile three or more boxes one on the other. The apes blundered a great deal in their building operations; they had little conception of the conditions requisite to make the structure a stable one. Their performances were curiously like those of very young children dealing with similar problems. They exhibited a type of intelligence far below that of an adult human being. But it was intelligence far above that of an ordinary mammal.

Several observers have described how apes and monkeys use sticks or other implements in order to get objects that are otherwise out of reach. Miss Romanes, in describing the behavior of a Cebus monkey, says that "if a nut or any object he wishes to get hold of is beyond the reach of his chain, he puts out a stick to draw it toward him, or if that does not succeed he stands upright and throws a shawl back over his head, holding it by the two corners ; he then throws it forward with all his strength, still holding on by the corners; thus it goes out far in front of him and covers the nut, which he then draws toward him by pulling in the shawl.”

Kohler's Sultan, who had learned to use a stick to draw in bananas that were placed beyond the bars of his cage, was given two hollow pieces of bamboo, one of which would fit into the other. Food was placed outside his cage beyond the reach of a single stick. At first Sultan would use one stick to poke the other one nearer the food. These efforts of course proved to be fruitless. After this, according to his keeper, “Sultan first of all squats indifferently on the box, which has been left standing a little back from the railings; then he gets up, picks up the two sticks, sits down again on the box and plays carelessly with them. While doing this, it happens that he finds himself holding one rod in either hand in such a way that they lie in a straight line (Fig. 3); he pushes the thinner one a little way into the opening of the thicker, jumps up and is already on the run toward the railings, to which he has up to now half turned his back, and begins to draw a banana toward him with the double stick.”

Sultan did not try to join two large pieces of bamboo together, but he sometimes tried to chew off a part of the end of a piece of wood that was too large to enter the hollow of a piece of bamboo and by forcing the pieces of wood and bamboo together made a jointed stick that he could use. To a certain extent, then, Sultan was not only a tool-using animal but a tool-making animal.

As Yerkes remarks, “Sharper contrast it would be difficult to imagine than that between the relatively blind and seemingly purposeless trial-and-error effort that has been described by Thorndike as typical for the cat when it faces novel problems and the definitely directed and apparently thoughtful behavior of the chimpanzee. The great apes

Fig. 3. — Köhler’s Sultan making a long stick of two pieces of bamboo to get a banana.

From Köhler’s The Mentality of Apes. (By permission of Harcourt, Brace & Company.)

Fig. 4.—Chang resents an injury to a companion.

exhibit ideational behavior; they act with insight. It remains for further patient, critical research to analyze this behavior more adequately and to compare it with our own action under identical conditions.”

One of the striking characteristics of apes and monkeys is the time and effort they spend in mere play. A cow, when her hunger is satisfied, is content to rest indefinitely. But not so the ape. He must be actively exploring, romping with his fellows, climbing, swinging, or pulling things to pieces. In this way he learns much about the properties of things in his environment. His ability to use his hands in manipulating objects gives him a great advantage over the lower mammals in adding to his store of knowledge. Along with his better structural equipment he is endowed with a strong natural curiosity, which is not confined merely to things that immediately affect his welfare but manifests itself in a sort of pure intellectual interest in objects per se. As the ape grows older his playfulness and his spontaneous curiosity gradually diminish, and he becomes more stolid, inactive, and incurious, like so many uneducated human beings.

Chimpanzees express joy and satisfaction by smiles and laughter, especially in play and when they are tickled or given a favorite food. They often show sympathy and affection in very human ways. Madam Abreu, in describing her efforts to catch one of her chimpanzees that had escaped and taken refuge in a mango tree, writes: “I went to the tree, and speaking to him pretended that I was injured in the arm and suffering. Immediately, on seeing that I was in trouble, he jumped from the tree and coming to me held my arm and kissed it strongly. And so we were able to catch him.”

“Impressive indeed,” says Dr. Yerkes, “‘is the thoughtfulness of the ordinarily care-free and irresponsible little chimpanzee for ill or injured companions. In the Abreu collection there was for a while opportunity to observe the social relations of three individuals whose age certainly was not above five years. In the same cage were a little male and two females, one of the latter mortally ill. She was so ill that much of the time she lay on the floor of the cage in the sunlight, listless and apathetic. There was excellent opportunity to observe the attitude of her lively companions toward this helpless invalid. In all their boisterous play they scrupulously avoiding disturbing her, and, in fact, seldom touched her as they climbed, jumped, or ran about the cage. Now and then one or the other would go to her and touch her gently or caress her; or again one of them, fatigued or worsted in some game, would obviously seek refuge and respite by going close to her. In this position safety from disturbance was assured. A certain solicitude, sympathy, and pity, as well as almost human expression of consideration were thus manifested by these little creatures.”

Chimpanzees are eminently social animals and are quick to resent an injury done to one of their number. (Fig. 4.) When one of them is punished “the whole group,” says Kohler, “sets up a howl, as if with one voice.” The excitement thus expressed has nothing of fear in it, and the group does not run away. On the contrary, they try to get to the place of punishment, even if they are separated from it by a railing. The lightest form of punishment, such as pulling the ear of the offender or a playful pretence at punishment, often stirred single members of a group to much more decisive action. “It was, in particular,” says Kohler, “little weak Konsul, who would run up excitedly, and, in the way little chimpanzees have of expressing their wishes, with a pleading countenance, stretch out his arm to the punisher, if the ape was still being punished, try to hold one arm tight, and finally, with exasperated gestures, start hitting out at the big man!” It is in fact dangerous to punish an ape among a number of adult animals. Even a slight, complaining sound may bring the whole pack in an angry assault upon the offending man. It matters little what the cause of the outcry. Even a good-tempered and affectionate chimpanzee may become suddenly infected with the epidemic of rage that seizes the group, and attack one with whom it had been playing a few moments before. Mob psychology among chimpanzees is only a little more impulsive and unreasoning than it is among ignorant human beings.

The desire of a chimpanzee to be a member of a group is inordinately strong. If isolated, he is very unhappy. Some fall a prey to fears; others cry, scream, and rage violently until overcome by exhaustion. If a chimpanzee is confined alone in a cage surrounded by his comrades, it often happens, says Köhler, “that if it is only possible for them to get near the prisoner’s cage, one or other of the animals will rush to it and put his arms round him through the bars. But he has to howl and cry for this affection to be shown him; as soon as he is quiet, the rest of them do not worry.”

The highly social and sympathetic nature of chimpanzees often leads them to form strong attachments to their keeper. They are quick to sense the emotional attitudes of their human companions and to guide their conduct accordingly. They have their favorites among human beings, often for reasons which appear quite capricious, and they are equally capricious in exhibiting strong dislikes to individual animals as well as persons. They wish to feel that they enjoy the favor of their keeper, and they become very jealous of his attentions to other animals. The pain felt by chimpanzees on account of the master's disfavor is well illustrated by the following story told by Köhler:

"When I had been in Tenerife a few weeks only, I noticed, whilst feeding the squatting animals, pressed up close to me, that a little female, at other times quite well-behaved, was snatching the food out of the hand of a weaker animal, and as she persisted in this, I gave her a little rap. The little creature, which I had punished for the first time, shrank back, uttered one or two heart-broken wails, as she stared at me horror-struck, while her lips were pouted more than ever. The next moment she had thrown her arms round my neck, quite beside herself, and was only comforted by degrees, when I stroked her. This need, here expressed, for forgiveness, is a phenomenon frequently to be observed in the emotional life of chimpanzees. Even animals who at first when they have been punished, boil with rage, throw one glances full of hate, and will not take a mouthful of food from a human being, when one comes again after a time, will press up close, with eager bearing, to which a quick rhythmic breathing and pulling open of the eyes is added; or else will give a sob of relief, press one's fingers affectionately to their lips and make other apish protests of friendship."

It appears evident that the little ape was concerned, not so much over her punishment, as over the fact that her master could bring himself to punish her at all. Like an affectionate and sensitive child, she felt keenly the estrangement which the punishment implied, and was satisfied only when cordial relations were again established.

A lack of space forbids a description of the many little ways in which the behavior of the higher apes resembles that of human beings. I can only mention their approach to dancing, their modes of beckoning to their comrades and of conveying by movements their meaning as to what they want others to do, their extraction of thorns and splinters from their own and others’ bodies, their modes of exhibiting affection, their natural hostility to strangers, and their gradual adoption of strangers into their group as they become better acquainted. For fuller information on these topics the reader may consult the works of Köhler and Yerkes, from which I have quoted.

I cannot, however, leave this topic without a few words on the family life of the apes and the care of parents for their offspring. Information on these topics is very meagre, because it is only very rarely that the larger apes have been bred in captivity. It has recently been established that the menstrual periods in female chimpanzees occur about every thirty days, and that the period of gestation is nine months—a fact ascertained from the birth of a young chimpanzee in the Abreu collection at Quinta Palatino, Cuba.

This baby chimpanzee was observed, soon after birth, in the lap of its mother, by whom it was cleaned and dried. It was quite devoid of hair except on the head. Lactation began on the second day, and the baby was nursed for several months. Incisor teeth appeared when the baby was two months old, and some of the molars developed during the next month. The mother was very solicitous for the welfare of her offspring. The father, who was somewhat morose, would often frighten the baby during his fits of temper, but was never known to molest it. Other male chimpanzees have been described as treating their young with gentleness and as playing with them.

The offspring of apes, as of most mammals, man included, receive more care and attention from the mother than from the father. Among the higher apes an adult male is often seen with one or a few adult females and a small group of younger individuals. The young cling tightly to the hair of the mother’s body, and when they are old enough to run about they quickly rush to the mother whenever they are alarmed. The mother chimpanzee appears to teach her offspring to walk by taking them by the hand and guiding their steps. The babies are unable to walk alone until they are several months old.

Young apes are sometimes disciplined by their parents, and they are generally obedient to parental calls. When ill, they become objects of increased solicitude. Captain Crow tells of a small monkey that became sick during a voyage. “It had always been a favorite with the other monkeys, who seemed to regard it as the last born and pet of the family; and they granted it many indulgences which they seldom conceded to one another. . . . From the moment it was taken ill their attention and care of it redoubled; and it was truly affecting and interesting to see with what anxiety and tenderness they tended and nursed the little creature. A struggle often ensued among them for priority in those offices of affection; and some would steal one thing and some another, which they would carry to it untasted, however tempting the bit might be to their own palates. Then they would take it up gently in their forepaws, hug it to their breasts, and cry over it as a fond mother would over her suffering child.”

The grief of monkeys and apes over the loss of their young has often been commented upon. After a young ape has died it is often difficult to remove the body, because the mother refuses to give it up even after it has begun to decay. The chimpanzee previously referred to, which had given birth to a baby in captivity, bore a second one about three years afterward, but it soon died. The mother would not allow it to be removed, so Madam Abreu contrived to slip a cord around the baby’s neck and when the mother's attention was averted, an attendant quickly jerked the body out of the cage. The monkey, Madam Abreu states, "cried and cried, and I did my best to console her."

Young apes as a rule take very kindly to human beings. Mr. Sheak states that he had "seen a young chimpanzee, taken from the shipping box in which he came to America, throw his arms about the neck of a man he had never seen before and hug him affectionately. I had once a little fellow who would snuggle up to me, then take my arm and put it about him." Throwing the arms about the neck or shoulders of another individual seems to be a natural and possibly instinctive mode of greeting among chimpanzees. Mr. Sheak, in describing the behavior of a tired chimpanzee when she observed her master getting out her sleeping box, states that "she gave forth two or three long-drawn-out notes, followed by sharp, quick, truncated barks of delight, rushed to her master and hugged him frantically, turned to me and hugged me till she almost choked me, then hurried over to a negro at the end of the stage and hugged him too." One seldom observes such exuberance of gratitude even in human beings.

Youth is the period in which apes are most companionable and attractive. As they get older and life grows more serious, their disposition is likely to become none too angelic. And the strength of these animals renders it unsafe to take chances with the uncertainty of their temper. There are, however, as many varieties of temperament among them as there are among people, and many adult apes remain safe and devoted companions even when they grow old. Chimpanzees especially are very emotional animals, and they habitually give free rein to their impulses, whether of affection or of pugnacity. Like children, they have not mastered the arts of inhibition and dissimulation, and they are therefore all the more interesting and instructive to the student of human nature. As we learn more of the ways of these creatures, it becomes more apparent to us not only that we are very much like them but that they are very much like us.

REFERENCES

• Darwin, C. R. The Descent of Man. New York, Appleton, 1871. The Expression of the Emotions in Man and Animals. New York, 1872.
• Hobhouse, L. T. Mind in Evolution. London, Macmillan, 1901.
• Holmes, S. J. The Evolution of Animal Intelligence. New York, Holt, 1911. Studies in Animal Behavior. Boston, Badger, 1916.
• Köhler, W. The Mentality of Apes. New York, Harcourt, Brace, 1925.
• Romanes, G. J. Animal Intelligence. New York, Appleton, 1883.
• Thorndike, E. L. Animal Intelligence. New York, Macmillan, 1911.
• Yerkes, R. M. Almost Human. New York, Appleton, 1925. The Intelligence of Chimpanzees. Baltimore, Williams and Wilkins, 1926.

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Dr. H. de Borlodot, delegate from the Catholic University of Lorraine to the Darwinian Centenary at Cambridge, said: “It is no exaggeration to say that in showing us a creation more grandiose than we had ever suspected it, Charles Darwin completed the work of Isaac Newton; because for all those whose ears are not incapable of hearing, Darwin was the interpreter of the organic world, just as Newton was the voice from heaven come to tell us of the glory of the Creator and to proclaim that the Universe is a work truly worthy of His hand.”