The Outline of History/Chapter 8

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VIII

THE ANCESTRY OF MAN[1]

§ 1. Man Descended from a Walking Ape. § 2. First Traces of Man-like Creatures. § 3. The Heidelberg Sub-man. § 4. The Piltdown Sub-man. § 5. The Riddle of the Piltdown Remains.

§ 1

THE origin of man is still very obscure. It is commonly asserted that he is "descended" from some man-like ape such as the chimpanzee, the orang-utang, or the gorilla, but that of course is as reasonable as saying that I am "descended" from some Hottentot or Esquimaux as young or younger than myself. Others, alive to this objection, say that man is descended from the common ancestor of the chimpanzee, the orang-utang, and the gorilla. Some "anthropologists" have even indulged in a speculation whether mankind may not have a double or treble origin; the negro being descended from a gorilla-like ancestor, the Chinese from a chimpanzee-like ancestor, and so on. These are very fanciful ideas, to be mentioned only to be dismissed. It was formerly assumed that the human ancestor was "probably arboreal," but the current idea among those who are qualified to form an opinion seems to be that he was a "ground ape," and that the existing apes have developed in the arboreal direction.

Of course, if one puts the skeleton of a man and the skeleton of a gorilla side by side, their general resemblance is so great that it is easy to jump to the conclusion that the former is derived from such a type as the latter by a process of brain growth and general refinement. But if one examines closely into one or two differences, the gap widens. Particular stress has recently been laid upon the tread of the foot. Man walks on his toe and his heel; his great toe is his chief lever in walking, as the reader may see for himself if he examines his own footprints on the bathroom floor and notes where the pressure falls as the footprints become fainter. His great toe is the king of his toes.

Among all the apes and monkeys, the only group that have their great toes developed on anything like the same fashion as man are some of
Possible Appearance of the Sub-man Pithecanthropus.
The face, jaws, and teeth are mere guess work (see text). The creature may have been much less human looking than this.
the lemurs. The baboon walks on a flat foot and all his toes, using his middle toe as his chief throw off, much as the bear does. And the three great apes all walk on the outer side of the foot in a very different manner from the walking of man.

The great apes are forest dwellers; their walking even now is incidental; they are at their happiest among trees. They have very distinctive methods of climbing; they swing by the arms much more than the monkeys do, and do not, like the latter, take off with a spring from the feet. They have a specially developed climbing style of their own. But man walks so well and runs so swiftly as to suggest a very long ancestry upon the ground. Also, he does not climb well now; he climbs with caution and hesitation. His ancestors may have been running creatures for long ages. Moreover, it is to be noted that he does not swim naturally; he has to learn to swim, and that seems to point to a long-standing separation from rivers and lakes and the sea. Almost certainly that ancestor was a smaller and slighter creature than its human descendants. Conceivably the human ancestor at the opening of the Cainozoic period was a running ape, living chiefly on the ground, hiding among rocks rather than trees. It could still climb trees well and hold things between its great toe and its second toe (as the Japanese can to this day), but it was already coming down to the ground again from a still remoter, a Mesozoic arboreal ancestry. It is quite understandable that such a creature would very rarely die in water in such circumstances as to leave bones to become fossilized.

It must always be borne in mind that among its many other imperfections the Geological Record necessarily contains abundant traces only of water or marsh creatures or of creatures easily and frequently drowned. The same reasons that make any traces of the ancestors of the mammals rare and relatively unprocurable in the Mesozoic rocks, probably make the traces of possible human ancestors rare and relatively unprocurable in the Cainozoic rocks. Such knowledge as we have of the earliest men, for example, is almost entirely got from a few caves, into which they went and in which they left their traces. Until the hard Pleistocene times they lived and died in the open, and their bodies were consumed or decayed altogether.

But it is well to bear in mind also that the Record of the Rocks has still to be thoroughly examined. It has been studied only for a few generations, and by only a few men in each generation. Most men have been too busy making war, making profits out of their neighbours, toiling at work that machinery could do for them in a tenth of the time, or simply playing about, to give any attention to these more interesting things. There may be, there probably are, thousands of deposits still untouched containing countless fragments and vestiges of man and his progenitors. In Asia particularly, in India or the East Indies, there may be hidden the most illuminating clues. What we know to-day of early men is the merest scrap of what will presently be known.

The apes and monkeys already appear to have been differentiated at the beginning of the Cainozoic Age, and there are a number of Oligocene and Miocene apes whose relations to one another and to the human line have still to be made out. Among these we may mention Dryopithecus of the Miocene Age, with a very human-looking jaw. In the Siwalik Hills of northern India remains of some very interesting apes have been found, of which Sivapithecus and Palæopithecus were possibly related closely to the human ancestor. Possibly these animals already used implements. Charles Darwin represents baboons as opening nuts by breaking them with stones, using stakes to prize up rocks in the hunt for insects, and striking blows with sticks and stones.[2] The chimpanzee makes itself a sort of tree hut by intertwining branches. Stones apparently chipped for use have been found in strata of Oligocene Age at Boncelles in Belgium. Possibly the implement-using disposition was already present in the Mesozoic ancestry from which we are descended.[3]

§ 2

Among the earliest evidences of some creature, either human or at least more man-like than any living ape upon earth, are a number of flints and stones very roughly chipped and shaped so as to be held in the hand. These were probably used as hand-axes. These early implements ("Eoliths") are often so crude and simple that there was for a long time a controversy whether they were to be regarded as natural or artificial productions.[4] The date of the earliest of them is put by geologists as Pliocene—that is to say, before the First Glacial Age. They occur also throughout the First Interglacial period. We know of no bones or other remains in Europe or America of the quasi-human beings of half a million years ago, who made and used these implements. They used them to hammer with, perhaps they used them to fight with, and perhaps they used bits of wood for similar purposes.[5]

But at Trinil, in Java, in strata which are said to correspond either to the later Pliocene or to the American and European First Ice Age, there have been found some scattered bones of a creature, such as the makers of these early implements may have been. The top of a skull, some teeth, and a thigh-bone have been found. The skull shows a brain-case about half-way in size between that of the chimpanzee and man, but the thigh-bone is that of a creature as well adapted to standing and running as a man, and as free, therefore, to use its hands. The creature was not a man, nor was it an arboreal ape like the chimpanzee. It was a walking ape. It has been named by naturalists Pithecanthropus erectus (the walking ape-man). We cannot say that it is a direct human ancestor, but we may guess that the creatures who scattered these first stone tools over the world must have been closely similar and kindred, and that our ancestor was a beast of like kind. This little trayful of bony fragments from Trinil is, at present, apart from stone implements, the oldest relic of early humanity, or of the close blood relations of early humanity, that is known.

While these early men or "sub-men" were running about Europe four or five hundred thousand years ago, there were mammoths, rhinoceroses, a huge hippopotamus, a giant beaver, and a bison and wild cattle in their world. There were also wild horses, and the sabre-toothed tiger still abounded. There are no traces of lions or true tigers at that time in Europe, but there were bears, otters, wolves, and a wild boar. It may be that the early sub-man sometimes played jackal to the sabre-toothed tiger, and finished up the bodies on which the latter had gorged itself.[6]

§ 3

After this first glimpse of something at least sub-human in the record of geology, there is not another fragment of human or man-like bone yet known from that record for an interval of hundreds of thousands of years. It is not until we reach deposits which are stated to be of the Second Interglacial period, 200,000 years later, 200,000 or 250,000 years ago, that another little scrap of bone comes to hand. Then we find a jaw-bone.

This jaw-bone was found in a sandpit near Heidelberg, at a depth of eighty feet from the surface,[7] and it is not the jaw-bone of a man as we understand man, but it is man-like in every respect, except that it has absolutely no trace of a chin; it is more massive than a man's, and its narrowness behind could not, it is thought, have given the tongue sufficient play for articulate speech. It is not an ape's jaw-bone; the teeth are human. The owner of this jaw-bone has been variously named Homo Heidelbergensis and Palæoanthropus Heidelbergensis, according to the estimate formed of its humanity or sub-humanity by various authorities. He lived in a world not remotely unlike the world of the still earlier sub-man of the first implements; the deposits in which it is found show that there were elephants, horses, rhinoceroses, bison, a moose, and so forth with it in the world, but the sabre-toothed tiger was declining and the lion was spreading over Europe. The implements of this period (known as the Chellean period) are a very considerable advance upon those of the Pliocene Age. They are well made but very much bigger than any truly human implements. The Heidelberg man may have had a very big body and large forelimbs. He may have been a woolly strange-looking creature.

§ 4

We must turn over the Record for, it may be, another 100,000 years for the next remains of anything human or sub-human. Then in a deposit ascribed to the Third Interglacial period, which may have begun 100,000 years ago and lasted 50,000 years,[8] the smashed pieces of a whole skull turn up. The deposit is a gravel which may have been derived from the washing out of still earlier gravel strata and this skull fragment may be in reality as old as the First Glacial period. The bony remains discovered at Piltdown in Sussex display a creature still ascending only very gradually from the sub-human.

The first scraps of this skull were found in an excavation for road gravel in Sussex. Bit by bit other fragments of this skull were hunted out from the quarry heaps until most of it could be pieced together. It is a thick skull, thicker than that of any living race of men, and it has a brain capacity intermediate between that of Pithecanthropus and man. This creature has been named Eoanthropus, the dawn man. In the same gravel-pits were found teeth of rhinoceros, hippopotamus, and the leg-bone of a deer with marks upon it that may be cuts. A curious bat-shaped instrument of elephant bone has also been found.[9]

There was, moreover, a jaw-bone among these scattered remains, which was at first assumed naturally enough to belong to Eoanthropus, but which it was afterwards suggested was probably that of a chimpanzee. It is extraordinarily like that of a chimpanzee, but Dr. Keith, one of the greatest authorities in these questions, assigns it, after an exhaustive analysis in his Antiquity of Man (1915), to the skull with which it is found. It is, as a jaw-bone, far less human in character than the jaw of the
Diagram to Illustrate the Riddle of the Piltdown Sub-man.
much more ancient Homo Heidelbergensis, but the teeth are in some respects more like those of living men.

Dr. Keith, swayed by the jaw-bone, does not think that Eoanthropus, in spite of its name, is a creature in the direct ancestry of man. Much less is it an intermediate form between the Heidelberg man and the Neanderthal man we shall presently describe. It was only related to the true ancestor of man as the orang is related to the chimpanzee. It was one of a number of sub-human running apes of more than ape-like intelligence, and if it was not on the line royal, it was at any rate a very close collateral.

After this glimpse of a skull, the Record for very many centuries gives nothing but flint implements, which improve steadily in quality. A very characteristic form is shaped like a sole, with one flat side stricken off at one blow and the other side worked. The archæologists, as the Record continues, are presently able to distinguish scrapers, borers, knives, darts, throwing stones, and the like. Progress is now more rapid; in a few centuries the shape of the hand-axe shows distinct and recognizable improvements. And then comes quite a number of remains. The Fourth Glacial Age is rising towards its maximum. Man is taking to caves and leaving vestiges there; at Krapina in Croatia, at Neanderthal near Düsseldorf, at Spy, human remains have been found, skulls and bones of a creature that is certainly a man. Somewhere about 50,000 years ago, if not earlier, appeared Homo Neanderthalensis (also called Homo antiquus and Homo primigenius), a quite passable human being. His thumb was not quite equal in flexibility and usefulness to a human thumb, he stooped forward, and could not hold his head erect, as all living men do, he was chinless and perhaps incapable of speech, there were curious differences about the enamel and the roots of his teeth from those of all living men, he was very thick-set, he was, indeed, not quite of the human species; but there is no dispute about his attribution to the genus Homo. He was certainly not descended from Eoanthropus, but his jaw-bone is so like the Heidelberg jaw-bone as to make it possible that the clumsier and heavier Homo Heidelbergensis, a thousand centuries before him, was of his blood and race.

§ 5

Upon this question of the Piltdown jaw-bone, it may be of interest to quote here a letter to the writer from Sir Ray Lankester, discussing the question in a familiar and luminous manner. It will enable the reader to gauge the extent and quality of the evidence that we possess at present upon the nature of these early human and sub-human animals. Upon these fragile Piltdown fragments alone more than a hundred books, pamphlets, and papers have been written. These scraps of bone are guarded more carefully from theft and wilful damage than the most precious jewels, and in the museum cases one sees only carefully executed fac-similes.

"As to the Piltdown jaw-bone, the best study of it is that by Smith Woodward, who first described it and the canine found later. The jaw is imperfect in front, but has the broad, flat symphysis of the Apes. G. S. Miller, an American anthropologist, has made a very good comparison of it with a chimpanzee's jaw, and concludes that it is a chimpanzee's. (His monograph is in the Am. Jour. of Phys. Anthrop., vol. i, no. 1.) The one point in the Piltdown jaw itself against chimpanzee identification is the smooth, flat, worn surface of the molars. This is a human character, and is due to lateral movement of the jaw, and hence rubbing down of the tubercles of the molars. This is not worth much. But the serious question is, are we to associate this jaw with the cranium found close by it? If so, it is certainly not chimpanzee nor close to the Apes, but decidedly hominid. Two other small fragments of crania and a few more teeth have been found in the gravel two miles from Piltdown, which agree with the Piltdown cranium in having superciliary ridges fairly strong for a human skull, but not anything like the great superciliary ridges of Apes. The fact one has to face is this; here you have an imperfect cranium, very thick-walled and of small cubical contents (1100 or so), but much larger in that respect than any ape's. A few yards distant from it in the same layer of gravel is found a jaw-bone having rather large pointed canines, a flat, broad symphysis, and other points about the inner face of the ramus and ridges which resemble those of the chimpanzee. Which is the more likely: (a) that these two novel fragments tending apewards from man were parts of the same individual; or (b), that the sweeping of the Wealden valley has brought there together a half-jaw and a broken cranium both more ape-like in character than any known human corresponding bits, and yet derived from two separate anthropoid beasts, one (the jaw) more simian, and the other (the cranium) much less so? As to the probabilities, we must remember that this patch of gravel at Piltdown, clearly and definitely, is a wash-up of remains of various later tertiary and post-tertiary deposits. It contains fragments of Miocene mastodon and rhinoceros teeth. These latter differ entirely in mineral character from the Eoanthropus jaw and the cranium. But (and this needs re-examination and chemical analysis) the Piltdown jaw and the Piltdown cranium do not seem to me to be quite alike in their mineral condition. The jaw is more deeply iron-stained, and I should say (but not confidently), harder than the cranium. Now, it is easy to attribute too much importance to that difference, since in a patch of iron-stained gravel, such as that at Piltdown, the soaking of water and iron salts into bones embedded may be much greater in one spot than in another only a yard off, or a few inches deeper!

"So I think we are stumped and baffled! The most prudent way is to keep the jaw and the cranium apart in all argument about them. On the other hand, on the principle that hypotheses are not to be multiplied beyond necessity, there is a case for regarding the two—jaw and cranium—as having been parts of one beast—or man."

To which Sir H. H. Johnston adds: "Against the chimpanzee hypothesis it must be borne in mind that so far no living chimpanzee or fossil chimpanzee-like remains have been found nearer England than north equatorial Africa or North-west India, and no remains of great apes at all nearer than Southern France and the upper Rhine—and those widely different from the Eoanthropus jaw."

  1. In this and the next chapters the writer has used Osborn's Men of the Stone Age, Sollas' Ancient Hunters, Dr. Keith's Antiquity of Man, W. B. Wright's The Quaternary Ice Age, Worthington Smith's Man, the Primeval Savage, F. Wood Jones' Arboreal Man, H. G. F. Spurrell's Modern Man and his Forerunners, O. T. Mason's Origins of Invention, Parkyn's History of Prehistoric Art, Salomon Reinach's Repertoire de l' Art Quaternaire, and various of the papers in Ray Lankester's Science from an Easy Chair.
  2. Darwin's Descent of Man.
  3. In Conquest for February, 1920, Mr. R. I. Pocock published a very useful criticism of this section as it stood in the first version of the Outline. It has been carefully modified in accordance with his views. In addition, we take the liberty of quoting the following:
    "It was formerly held, I believe, that, so far as habits are concerned, the transitional steps in man's descent were to be traced from an active arboreal monkey to the equally active arboreal gibbon, and thence to the less active, but still mainly arboreal, orang-utang; from the latter to the half arboreal, half terrestrial chimpanzee, thence, through the mainly terrestrial gorilla, to wholly terrestrial man. In other words, the stages of man's evolution were a series of structural modifications resulting from the gradual dropping of the ancestral habit of living in trees in favour of life on the ground. But such a conception leaves unexplained the great differences between monkeys and gibbons in arboreal and terrestrial activity. Were it correct, we should expect the gibbons to show a transition between monkeys and other apes in their method of moving through trees and on the ground. They show no such transition. It is necessary, therefore, to formulate another theory.
    "Since all the active climbing monkeys have well-developed tails, and since the tail tends to shorten or disappear in species of less active habits which live, like the monkey of Gibraltar, on rocky hillsides, the absence of the tail in apes suggests very forcibly that their ancestor had to a great extent given up living in trees. Moreover, the short broad foot of the apes, their ability to stand and walk erect, their peculiar way of climbing, all point to the conclusion that they are descended, not from a truly arboreal ape, but from an ape which had already taken to terrestrial life, with partly bipedal, partly quadrupedal progression; an ape which, while still retaining the power to ascend trees for purposes of feeding and escaping from carnivorous foes, was, at best, probably a slow, inactive climber, certainly not an arboreal leaper like a monkey. A large ape of that mode of life, with hands and feet not very different from those of a chimpanzee or gorilla, but with stronger legs and shorter arms, is my conception of the ancestor of existing apes and of man. And the progenitor of that hypothetical ancestor was probably a big ground monkey."
  4. Among the earlier pioneers of the latter view was Mr. Harrison, a grocer of Ightham in Kent, one of those modest and devoted observers to whom British geology owes so much. At first his "Eoliths" were flouted and derided by archæologists, but to-day he has the scientific world with him in the recognition of the quasi-human origin of many of his specimens. With him we must honour Mr. W. J. Lewis Abbott, a jeweller of St. Leonards, whose intimate knowledge of stone structure has been of the utmost value in these discussions. See "Occ. Papers," No. 4, of the Royal Anthropl. Inst., for a description by Sir E. R. Lankester of one of the better formed of these early implements.
  5. Some writers suppose that a Wood and Shell age preceded the earliest Stone Age. South Sea Islanders, Negroes, and Bushmen still make use of wood and the sharp-edged shells of land and water molluscs as implements.
  6. For some interesting suggestions on the origin of flint implements see Elliot Smith's presidential address to the Anthropl. Sect. of the Brit. Assn., 1912.
  7. Sollas' Ancient Hunters, p. 40.
  8. We follow Penck.
  9. For sixpence and postage the reader can get from the British Museum, South Kensington, a very fully illustrated pamphlet A Guide to the Fossil Remains of Man, showing the Piltdown material in great detail.