The Immense Journey Read online

  We are now in a position to see the wonder and terror of the human predicament: man is totally dependent on society. Creature of dream, he has created an invisible world of ideas, beliefs, habits, and customs which buttress him about and replace for him the precise instincts of the lower creatures. In this invisible universe he takes refuge, but just as instinct may fail an animal under some shift of environmental conditions, so man’s cultural beliefs may prove inadequate to meet a new situation, or, on an individual level, the confused mind may substitute, by some terrible alchemy, cruelty for love.

  The profound shock of the leap from animal to human status is echoing still in the depths of our subconscious minds. It is a transition which would seem to have demanded considerable rapidity of adjustment in order for human beings to have survived, and it also involved the growth of prolonged bonds of affection in the subhuman family, because otherwise its naked, helpless offspring would have perished.

  It is not beyond the range of possibility that this strange reduction of instincts in man in some manner forced a precipitous brain growth as a compensation—something that had to be hurried for survival purposes. Man’s competition, it would thus appear, may have been much less with his own kind than with the dire necessity of building about him a world of ideas to replace his lost animal environment. As we will show later, he is a pedomorph, a creature with an extended childhood.

  Modern science would go on to add that many of the characters of man, such as his lack of fur, thin skull, and globular head, suggest mysterious changes in growth rates which preserve, far into human maturity, foetal or infantile characters which hint that the forces creating man drew him fantastically out of the very childhood of his brutal forerunners. Once more the words of Wallace come back to haunt us: “We may safely infer that the savage possesses a brain capable, if cultivated and developed, of performing work of a kind and degree far beyond what he ever requires it to do.”

  As a modern man, I have sat in concert halls and watched huge audiences floating dazed on the voice of a great singer. Alone in the dark box I have heard far off as if ascending out of some black stairwell the guttural whisperings and bestial coughings out of which that voice arose. Again, I have sat under the slit dome of a mountain observatory and marveled, as the great wheel of the galaxy turned in all its midnight splendor, that the mind in the course of three centuries has been capable of drawing into its strange, nonspatial interior that world of infinite distance and multitudinous dimensions.

  Ironically enough, science, which can show us the flints and the broken skulls of our dead fathers, has yet to explain how we have come so far so fast, nor has it any completely satisfactory answer to the question asked by Wallace long ago. Those who would revile us by pointing to an ape at the foot of our family tree grasp little of the awe with which the modern scientist now puzzles over man’s lonely and supreme ascent. As one great student of paleoneurology, Dr. Tilly Edinger, recently remarked, “If man has passed through a Pithecanthropus phase, the evolution of his brain has been unique, not only in its result but also in its tempo.… Enlargement of the cerebral hemispheres by 50 per cent seems to have taken place, speaking geologically, within an instant, and without having been accompanied by any major increase in body size.”

  The true secret of Piltdown, though thought by the public to be merely the revelation of an unscrupulous forgery, lies in the fact that it has forced science to reëxamine carefully the history of the most remarkable creation in the world—the human brain.

  1 Symposia of the Society for Experimental Biology, VII, Evolution (New York: Academic Press, 1953), p. 395.

  THE MAZE

  Shortly after I had expressed my conclusions about the real secret of Piltdown, I was roundly castigated by a few people who had construed my remarks as an attack upon Darwin and thus an assault upon the theory of evolution itself. A surprising amount of suppressed emotion still lingers about these hundred-year-old controversies, and those who are not historical-minded may be quick to launch themselves, sometimes more valiantly than accurately, into the thick of some forgotten fray. Along an advancing front of science, the man who writes for a nontechnical public runs risks and has curious experiences. Sometimes he is unlucky, as in the case of an acquaintance of mine whose article dealing soberly with the Piltdown skull appeared at the very moment when the hoax was denounced in the press. Sometimes, on the other hand, he may have almost preternatural luck, in that unexpected events may further substantiate a view that he had earlier broached in hesitation and with a minimum of supporting evidence.

  After I had expressed myself upon the dangerously controversial subject of the human brain—and I say this avowedly, though so distinguished an authority upon the great apes as Solly Zuckerman has spoken of the “enormous gap” which exists “between the intelligence of Man and that of any other Primate”—two quite astonishing things happened. The first of these it is my intention to chronicle in this chapter; the second event, and the final culmination of the plot, will have to be reserved for the one which follows. The first happening, as it was described in the press, seemed to be a total negation of much that has been expressed in my treatment of the Piltdown story, namely, the recency of man.

  The reader may remember that in March of 1956 curious and startling headlines began to appear in the newspapers. In the first excitement it must have seemed to the layman that the whole theory of evolution was about to be overthrown. There were accounts in the press of a ten-million-year-old “human” fossil. Such a discovery seemed, at first thought, to contradict what I had contended was the great youth of man, that is, man as a culture bearer, a user of speech.

  The commotion had been touched off by the arrival in New York City of a paleontologist from Switzerland bearing the bones of a small primate long known to science as Oreopithecus. Johannes Hurzeler of Basel presented to a group of scholars gathered at the Wenner-Gren Foundation for Anthropological Research his view that the bones of Oreopithecus showed human rather than anthropoid affinities. Since these bones are estimated to be ten million years older than the earliest known fossil men, his announcement made headlines.

  “Fossil Research Questions Darwin Evolution Theory,” the New York Times announced. The Herald Tribune editorialized: “No Missing Link?” Specialists on fossil man were besieged by telephone calls from reporters and by faintly derisive queries from anti-evolutionists whose interest had already been whetted by the Piltdown hoax. Perhaps this new contradiction would mark the final exit of the man-monkey and of the anthropologists along with it.

  By the time scientists had begun to respond, the press had passed on to other things, leaving in the mind of the public a confused vision of a sort of “little man” who, so the newspapers said, had been found in a coal mine in Tuscany. Like most such episodes, that of Oreopithecus has a history, and the argument over it is of the same general nature as two similar controversies fought within the memory of men now living.

  The incident has served to draw attention to a long-existing debate among anthropologists, which has occasionally waxed acrimonious. The partisans divide basically into two schools: the school of the “little man” and that of the “apeman.” The former pursue the figure of man backward until, upon some far wall in time, it appears as a dwarfed, big-headed little shadow; the latter see our earliest ancestor shambling into the light like some great shaggy anthropoid. The argument recalls the ancient dispute between the preformationists, who saw in the human sperm cell a preformed homunculus, or little man, which had only to grow to adult size, and the epigenesists, who judged correctly that each embryo acquires the characteristics of a human being only through development.

  Some anthropologists search for human characters—vertical front teeth, a shortened face, an expanded brain case—early in the human line of descent. They seek, in other words, for something dangerously close to the homunculus of the preformationists. They “prove” evolution by finding, as St. George Jackson Mivart said in 1874, “an ancestr
al form so like man [that] we have the virtual pre-existence of man’s body supposed, in order to account for the actual first appearance of that body as we know it.”

  The more thoroughgoing evolutionists, in contrast, have looked for forms which contained only the possibility of development into man. Such students have generally regarded man as a relatively recent emergent from a group of primates which also gave rise to the modern great apes; in other words, the comparison of man with the anthropoids of today has been based on the assumption that they and we had ancestors in common.

  Charles Darwin was not the first to notice our likeness to the monkeys and apes. Such observations extend into antiquity, and by the eighteenth and early nineteenth centuries philosophers were arranging the primates in an order of complexity. As voyagers began to come into contact with primitive peoples, these were often placed on the scale as grades between the anthropoids and civilized European man. The Hottentots of the Cape of Good Hope particularly appealed to the Western mind as candidates for such a place; it was said that their language was only a step above the chatter of apes.

  Thus notions of the “missing link” were in existence long before Darwin and long before the appearance of a truly evolutionary philosophy. Darwin himself cautiously refrained from attempting to trace man’s precise relationship to the apes. But some of his followers, notably T. H. Huxley, tackled the problem head on. Huxley was provoked to his excursion into man’s past by events at the famous meeting of the British Association for the Advancement of Science at Oxford in 1860. He had borne the brunt of the conservatives’ attacks on evolution. At this meeting Richard Owen, England’s foremost comparative anatomist and a mortal enemy of Darwin and his followers, attempted to maintain man’s unique position in the animal world by placing him in a distinct subclass of the mammals for which he proposed the name “Archencephala.” This classification was based upon brain characters which Owen maintained did not occur in the lower primates. Huxley, his ire aroused, set out to demonstrate that Owen was wrong, that man was closely related to the other primates. He composed a series of lectures which were published in 1863 under the title Evidence as to Man’s Place in Nature.

  In this work, which more or less set the pattern for much that followed, Huxley thoroughly demolished Owen’s position. He took the view that “the surface of the brain of a monkey exhibits a sort of skeleton map of man’s, and in the manlike apes the details become more and more filled in, until it is only in minor characters … that the chimpanzee’s or the orang’s brain can be structurally distinguished from man’s.” Huxley was quite willing to admit that man’s own origin was obscure and might go back millions of years to a common ancestor, but he insisted that the modern apes were our closest surviving relatives. If Huxley dwelt too heavily and too emotionally upon anatomical correspondence between ourselves and the great apes, it must be remembered that at the time he wrote the evolutionists were fighting primarily for a principle, against the orthodox “special creationists.” Furthermore, it must also be remembered that very few human fossils had been discovered, and these were fragmentary. Our living relatives in the trees could be seen at the zoo, and it was inevitable that they should dominate man’s imagination. Serious scholars even came to believe that microcephalic idiots were throwbacks to some remote period of the human past.

  By the beginning of the twentieth century the ape origins of modern man seemed pretty well established. The finding of the Pithecanthropus skull cap had bolstered this view. Many felt that from a form something like that of a chimpanzee it was an easy step to the Java man and thence on to Neanderthal and modern man. But at the turn of the century there came a new revolt against the ape.

  The attention of anatomists was attracted to a small, tree-living creature in southeast Asia possessing definite characters of a primate. The tarsier (Tarsius spectrum), an animal with enormous eyes and about the size of a small kitten, has a brain and other characteristics which ally it to the lower monkeys. In 1918, F. Wood Jones, a distinguished English anatomist, had expressed the heretical view, which he has maintained and developed since, that man arose from a tarsioid rather than from an anthropoid ancestry.

  Wood Jones insists that the human line is very ancient, going back to a past tens of millions of years old in the Tertiary Period He predicts that man’s immediate ancestors, if ever discovered, “will be utterly unlike the slouching, hairy ‘ape-men’ of which some have dreamed … and will be found in geological strata antedating the heyday of the great apes.” The ancestors of man, he says, were “small, active animals” already endowed with legs longer than their arms, small jaws without protruding teeth, and enlarged craniums. They were not swingers in trees: the human hand and foot, he contends, are too specialized to have been made over rapidly from an arboreal ancestor’s. The present-day tarsiers in the trees, according to his view, evolved their tree-living specializations later, but our early tarsioid ancestor walked on the ground.

  Wood Jones’s proto-man thus sounds like a homunculus. When he first advocated his views, he found very few followers. Henry Fairfield Osborn, the late paleontologist, though not a Wood Jones follower, inclined toward a homuncular dawn man going back to early Tertiary times many millions of years ago. “I predict,” he said, “that even in Upper Oligocene time we shall find pro-men, and that they will have pro-human limbs.”

  Wood Jones and Osborn were vigorously refuted by primatologists who championed the orthodox view that man was a “made-over ape.” They insisted that man’s immediate forerunners could not be so ancient as Wood Jones and Osborn said “It seems anachronistic,” wrote William King Gregory, “to attribute to the very remote Tertiary ancestors of man the long legs, long thumbs, big brain, short face, small canines, etc., which are now diagnostic characters.” But by the 1940’s the “made-over ape” point of view had moderated The most important factor in this change was the discovery in South Africa of the fossil Proconsul africanus—a creature of the early Miocene (about twenty million years ago) which combined characters of early Old World monkeys and great apes. William L. Straus, Jr., of the Johns Hopkins University, voiced a suspicion that man’s immediate ancestors might have been “more monkey-like than anthropoid-like.” Straus, who takes a very sane and cautious position on this lengthy controversy over the human ancestry, feels that the anthropoid-ape theory is weakest in its failure to account for anatomical traits which man shares with the monkeys and lemurs. More recently W. C. Osman Hill, the well-known English primatologist, has come to believe that man branched off the primate stock below the great-ape line. He even suggests that Straus’s view might be reconciled with Wood Jones’s tarsioid hypothesis if some early Oligocene monkey of tarsioid affinities were admitted on the line leading to man—a form, say, like Parapithecus.

  Thus, before Hurzeler’s recent announcement a slow shift of thought or widening of possible horizons had been under way in the study of human evolution. The theory that man came down late out of the trees has been dropped in some quarters and is less explosively defended in others. There is a greater willingness to reserve judgment and wait upon new evidence. It was in this receptive atmosphere that Hurzeler presented his new study of Oreopithecus.

  The fossil has been known since 1872, when it was described by the French paleontologist Paul Gervais, who regarded it as an Old World monkey. Hurzeler, after studying the original fossil and later finds, has become convinced that Oreopithecus is the first manlike form discovered in the Tertiary Period—it is believed to date from the Miocene. He apparently bases this view upon certain technical features of the teeth, including the nonprojecting canines, the vertical bite and the shortened face. It must be noted, however, that only parts of the skull have been found, and its full shape cannot be reconstructed.

  Oreopithecus is a lower “monkey,” in popular terms. It is not a “man” in the sense that many reporters assumed it to be, in spite of “no tooth gaps, no apelike protruding jaw,” and so on. There are both fossil and still living pri
mates which would have no trouble in answering that description, yet I am sure no one would call them men.

  So the substance of the story is that Hurzeler has revived interest in a problematical bit of bone we have long been fingering. For the successful reconstruction of the evolution of the horse in the Tertiary Period, paleontologists had thousands of fossil bones to study. Primatologists may therefore be forgiven their fumblings over great gaps of millions of years from which we do not possess a single complete monkey skeleton, let alone the skeleton of a human forerunner. For the whole Tertiary Period, which involves something like sixty to eighty million years, we have to read the story of primate evolution from a few handfuls of broken bones and teeth. Those fossils, moreover, are from places thousands of miles apart on the Old World land mass.

  If we were able to follow every step of man’s history backward into time, we would see him divested, rag by rag and stitch by stitch, of every vestige of his human garment. That divestment, however, would not occur all at one place. If we accept the evidence of evolution, we must assume that man became man by degrees, that he emerged out of the animal world by the slow accumulation of human characters over long ages—save for that seemingly rapid spurt in brain growth, which has carried him so far from his other relatives.

  Our knowledge at present is not sufficient to establish precisely what anatomical traits are peculiarly human. As Straus has very aptly pointed out: “It is this general lack of structural specialization that makes the study of primate phylogeny so difficult.” Some traits may have been paralleled in primate lines of evolution which did not lead to man; some traits called human may represent old generalized characters which have survived in man and been lost in some of his modern specialized relatives.