Anomalous Evidence
The Song of the Red Lion
One evening in 1871, an association of learned British gentlemen, the Red lions, gathered in Edinburgh, Scotland, to feed happily together and entertain each other with humorous songs and speeches. Lord Neaves, known well for his witty lyrics, stood up before the assembled lions and sang twelve stanzas he had composed on “The origin of species a la Darwin.” Among them:
An Ape with a pliable thumb and big brain,
When the gift of gab he had managed to gain,
As Lord of Creation established his reign
Which Nobody can Deny!
His listeners responded, as customary among the Red lions, by gently roaring and wagging their coattails (Wallace 1905, p. 48).
1.1 Darwin Hesitates
Just a dozen years after Charles Darwin published The Origin of Species in 1859, growing numbers of scientists and other educated persons considered it impossible, indeed laughable, to suppose that humans were anything other than the modified descendants of an ancestral line of apelike creatures. In The Origin of Species itself, Darwin touched but briefly on the question of human beginnings, noting in the final pages only that “Light will be thrown on the origin of man and his history.” Yet despite Darwin’s caution, it was clear that he did not see humanity as an exception to his theory that one species evolves from another.
Other scientists were not as hesitant as Darwin to directly apply evolutionary theory to the origin of the human species. For these scientists, Darwinism helped explain the remarkable similarity between humans and apes. Even before Darwin published The Origin of Species, Thomas Huxley had been investigating anatomical similarities between apes and humans. Huxley clashed with Richard Owen, who insisted that human brains had a unique feature—the hippocampus major. At a meeting of the British Association for the Advancement of science in 1860, Huxley presented evidence showing that brains of apes also had the hippocampus major, thus nullifying a potential objection to the idea that humans had evolved from apelike ancestors. Exuding his usual self-confidence, Huxley (Wendt 1972, p. 71) had written his wife before the British Association meeting: “By next Friday evening they will all be convinced that they are monkeys!”
Huxley did not limit himself to convincing scientists of this proposition. He delivered to working men a series of lectures on the evolutionary connection between humans and lower animals, and in 1863 he published Man’s Place in Nature, in which he summarized in popular form his arguments for human descent from an apelike creature by the mechanism of Darwinian evolution. In his book, Huxley presented detailed evidence showing the similarity of the human anatomy to that of the chimpanzees and gorillas. The book, intended for general readership, inspired violent criticism but sold well. Scientists continue to use the similarity between humans and apes as an argument in favor of the evolution of humans from apelike ancestors.
Scientists have extended the argument to the molecular level, and have presented evidence showing that there is 99 percent agreement between the DNA sequences of human genes and the corresponding genes of chimpanzees. This certainly suggests a close relationship between humans and chimpanzees, and on a broader scale the shared biochemical mechanisms of living cells indicate a relationship between all living organisms. However, the mere existence of patterns of similarity does not tell us what this relationship is. From an a priori standpoint, it could be a relationship of descent by Darwinian evolution, or it could be something quite different. To actually show evolutionary descent, it is necessary to find physical evidence of transforming sequences of ancestors.
In a companion volume to this book, we will fully discuss the argument that the genealogical tree of human descent can be traced out using biomolecular studies involving mitochondrial DNA and other genetic material. For now, we shall simply point out that interpretation of patterns of molecular similarity in terms of genealogical trees presupposes (rather than proves) that the patterns came about by evolutionary processes. In addition, the assignment of ages to such patterns of relationships depends on archeological and paleoanthropological studies of ancient human or near human populations. Thus, in the end, all attempts to show the evolution of species (the human species in particular) must rely on the interpretation of fossils and other remains found in the earth’s strata.
By the time Darwin published The Origin of Species in 1859, some key finds relevant to human origins had already been made. About 15 years previously, Edouard Lartet had found in Miocene strata at Sansan in southern France the first fossils of Pliopithecus, an extinct primate thought to be ancestral to the modern gibbons. About this discovery Lartet wrote in 1845: “This corner of ground once supported a population of mammals of much higher degree than those here today. . . . Here are represented various degrees in the scale of animal life, up to and including the Ape. A higher type, that of the human kind, has not been found here; but we must not hastily conclude from its absence from these ancient formations that it did not exist” (Boule and Vallois 1957, pp. 17–18). Lartet was hinting that human beings might have existed in Miocene times, over 5 million years ago, an idea that would not win any support from today’s scientists.
In 1856, Lartet reported on Dryopithecus, a fossil ape discovered by Alfred Fontan near Sansan. This Miocene ape is thought to be anatomically related to the modern chimpanzees and gorillas. Although Pliopithecus and Dryopithecus provided Darwinists with possible distant ancestors for humans and modern apes, there were no fossils of intermediate beings connecting humans with these Miocene primates. However, in the same year Lartet reported on Dryopithecus, the first evidence that intermediate prehuman forms may have existed was found in the Neander valley in Germany.
1.2 The Neanderthals
In the latter part of the seventeenth century, a minor German religious poet and composer named Joachim Neumann sometimes wandered through the Dussel River valley, in solitary communion with nature. He used the pseudonym Neander, and after his death the local people called the valley the Neanderthal. Two centuries later, others came to the pleasant little valley of the Dussel not for peace of mind but to quarry limestone for the Prussian construction industry. One day in August of 1856, while excavating the Feldhofer cave high on a steep slope of the valley, some workmen discovered human fossils and gave them to Herr Beckershoff. Beckershoff later dispatched a skullcap and some other large bones to J. Carl Fuhlrott, a local schoolteacher with a well-known interest in natural history. Recognizing the fossils as possible evidence of humanity’s great antiquity, Fuhlrott in turn gave them to Herman Schaffhausen, a professor of anatomy at the University of Bonn.
At this time, most of the scientists considering the question of human antiquity believed that Europe had once been inhabited by a roundheaded primitive race who used tools of stone and bronze. This race had later been replaced by an invading longheaded race who knew how to use iron. The two races were not, however, regarded as being linked by evolution. In 1857, Professor Schaaffhausen delivered reports to scientific gatherings in Germany, calling the newly discovered Neanderthal man a representative of a “barbarous aboriginal race,” perhaps descended from the wildmen of northwestern Europe mentioned in the works of various Roman authors such as Virgil and Ovid. Schaffhausen called special attention to the Neanderthal skull’s primitive features—its thick bone structure and its pronounced brow ridges—as evidence of its antiquity and difference from the modern racial type. Others suggested it was simply the skull of a modern man, heavily deformed by disease. And there the matter rested until 1859, when Darwin published The Origin of Species, setting off intense speculation about humanity’s possible descent from more primitive apelike creatures.
The Neanderthal discovery was then no longer a topic for discussion only among the members of the Natural History Society of the Prussian Rhineland and Westphalia. The heavyweights of European science moved in to pass judgement. Charles Lyell, then recognized as the world’s preeminent geologist, came to Germany and personally investigated both the fossils and the cave in which they had been found. He felt nothing conclusive could be deduced from the Neanderthal skeleton. For one thing it was “too isolated and exceptional” (Lyell 1863, p. 375). How could generalizations about human prehistory be drawn from just one set of bones which happened to have some “abnormal and ape-like” features? Lyell also felt that its age was “too uncertain.” The unstratified cave deposits in which it had been found could not be assigned a place in the sequence of geological periods. Accompanying animal fossils might have helped establish the age of the Neanderthal man, but none had been found.
Many scientists, especially those opposed to evolutionary doctrines, thought the skeleton was that of a pathologically deformed individual of the recent era. The German anatomist Rudolf Virchow, for example, believed the crude features of the Neanderthal specimen could be explained by deformities resulting from rickets and arthritis. Thirty years after first expressing this opinion in 1857, Virchow still held it, and also continued to dismiss the idea that the Neanderthal bones represented a stage in human evolution from lower species. “The idea that men arose from animals,” said Virchow, “is entirely unacceptable in my view, for if such transitional men had lived there would be evidence of it, and such evidence does not exist. The creature preliminary to man has just not been found” (Wendt 1972, pp. 57–58).
A British scientist argued that the “skull belonged to some poor idiotic hermit whose remains were found in the cave where he died” (Goodman 1982, p. 75). Dr. F. Mayer, an anatomist at Bonn University suggested, like Virchow, that the Neanderthal man’s bent leg bones had been caused by childhood rickets, or perhaps many years of horse riding. In 1814, Cossack cavalry had moved through the area in pursuit of napoleon’s army. Was the Neanderthal man a wounded Cossack who had crawled into the cave and died? Mayer saw this as a distinct possibility. But Thomas Huxley, writing in Natural History Review (1864), asked how a dying soldier got in a cave 60 feet up a steep valley wall and buried himself. And where was his uniform?
An old skull dug up at Forbe’s Quarry, during the building of fortifications at Gibraltar in 1848, entered the discussion. on investigation, the fossil skull had turned out to be quite similar to the Feldhofer cave specimen, prompting George Busk, professor of anatomy at the Royal college of surgeons, to write in 1863: “the Gibraltar skull adds immensely to the scientific value of the Neanderthal specimen, showing that the latter does not represent . . . a mere individual peculiarity, but that it may have been characteristic of a race extending from the Rhine to the Pillars of Hercules. . . . Even Professor Mayer will hardly suppose a rickety Cossack engaged in the campaign of 1814 had crept into a sealed fissure in the Rock of Gibraltar” (Goodman 1982, p. 77).
In 1865, Hugh Falconer said the Gibraltar skull represented “a very low type of humanity—very low and savage, and of extreme antiquity—but still a man and not halfway between a man and a monkey and certainly not the missing link” (Millar 1972, p. 62). In similar fashion, Huxley concluded, after examining the detailed drawings of the Neanderthal skull sent to him by Lyell, that the Neanderthals were not the missing link sought by scientists. Despite the skull’s somewhat primitive features and its apparent great age, it was in Huxley’s opinion quite close to the modern type, close enough to be classified as simply a variation. “In no sense,” he said, “can the Neanderthal bones be regarded as the remains of a human being intermediate between men and Apes” (Huxley 1911, p. 205). Most modern scientists agree with Huxley’s analysis and see the Neanderthals as a recent offshoot from the main line of human evolution. The Neanderthals are sometimes designated Homo sapiens neanderthalensis, indicating a close relationship with the modern human type.
Huxley (1911, pp. 207–208) then went on to ask, “Where then, must we look for primaeval man? Was the oldest Homo sapiens Pliocene or Miocene, or yet more ancient? In still older strata do the fossilized bones of an ape more anthropoid, or a man more pithecoid, than any yet known await the researches of some unborn paleontologist? Time will show.”
1.3 Haeckel and Darwinism
Possible intermediate forms between humans and apes were of great concern to the German anatomist Ernst Haeckel. Haeckel, whose specialty was embryology, was an avid advocate of Darwin’s theory of evolution by natural selection. He was also famous for his own theory that ontogeny, the step-by-step growth of an animal (or human) embryo, faithfully represents the creature’s phylogeny, or evolutionary development over millions of years from a simple, one-celled organism. However, this theory, which is summed up by the slogan “ontogeny recapitulates phylogeny,” has long been rejected by twentieth-century scientists.
Haeckel had illustrated his theory with drawings of embryos of different kinds of animals. Unfortunately, some of his drawings turned out to be fakes, and he was tried before the Court of Jena University on charges of fraud. in his defense he declared: “A small percent of my embryonic drawings are forgeries: those namely, for which the observed material is so incomplete or insufficient as to compel us to fill in and reconstruct the missing links by hypothesis and comparative synthesis. I should feel utterly condemned . . . were it not that hundreds of the best observers and biologists lie under the same charge” (Meldau 1964, p. 217). If Haeckel’s sweeping accusation is correct, this may have important bearing on the mode of anatomical reconstruction employed for the many “missing links” we will discuss in this book.
Haeckel’s enthusiasm for Darwinism was boundless, and he showed no hesitation in proclaiming the essence of the theory, the survival of the fittest, as the foundation of his whole view of reality. An early advocate of social Darwinism, he said: “A grim and ceaseless struggle for life is the real mainspring of the purposeless drama of the world’s history. We can only see a ‘moral order’ and ‘design’ in it when we ignore the triumph of immoral force and the aimless features of the organism. Might goes before right as long as the organism exists” (Haeckel 1905, p. 88).
In Descent of Man, Darwin himself (1871, p. 501) wrote: “With savages, the weak in body and mind are soon eliminated and those that survive commonly exhibit a vigorous state of health. We civilized men, on the other hand, do our utmost to check the process of elimination; we build asylums for the imbecile, the maimed, and the sick; we institute poor-laws; and our medical men exert their utmost skill to save the life of every one to the last moment. . . . Thus the weak members of civilized societies propagate their kind. No one who has attended to the breeding of domestic animals will doubt that this must be highly injurious to the race of man. . . . Hardly anyone is so ignorant as to allow his worst animals to breed.” modern supporters of Darwin’s theory routinely downplay such unsettling statements.
Haeckel was one of the first to compose the familiar phylogenetic tree, showing different groups of living beings related to each other like branches and limbs coming from a central trunk. At the top of Haeckel’s tree is found Homo sapiens. His immediate predecessor was Homo stupidus, “true but ignorant man.” And before him came Pithecanthropus alalus, the “apeman without speech”—the missing link. Haeckel scored another first by commissioning a highly realistic painting of Pithecanthropus alalus, thus starting the longstanding tradition of presenting hypothetical human ancestors to the general public through the medium of lifelike pictures and statues.
Haeckel published his view of human evolution in 1866, in General Morphology of Organisms, and in 1868, in Natural History of Creation. These books appeared several years before Darwin came out with Descent of Man, in which Darwin acknowledged Haeckel’s work. Haeckel believed humans had arisen from a primate ancestor in south Asia or Africa: “considering the extraordinary resemblance between the lowest woolly-haired men, and the highest man-like apes . . . it requires but a slight imagination to conceive an intermediate form connecting the two” (Spencer 1984, p. 9).
1.4 The search Begins
In his book The Antiquity of Man, first published in 1863, Charles Lyell, like Huxley and Haeckel, expressed the belief that fossils of a creature intermediate between the apes and humans would someday be found. The most likely places were “the countries of the anthropomorphous apes . . . the tropical regions of Africa and the islands of Borneo and Sumatra” (Lyell 1863, p. 498).
Of course, it should be kept in mind that the missing link was not expected to connect modern humans with modern monkeys, but instead with the fossil apes. The first human ancestor, it was thought, must have branched off from the old World monkeys sometime before the Miocene period. As Darwin himself stated (1871, p. 520): “We are far from knowing how long ago it was when man first diverged from the Catarrhine [Old World monkey] stock; but it may have occurred at an epoch as remote as the Eocene period; for that higher apes had diverged from the lower apes as early as the upper Miocene period is shown by the existence of Dryopithecus.”
Dryopithecus is still recognized as an early precursor of the anthropoid or humanlike apes, which include gorillas, chimpanzees, gibbons, and orangutans. As previously noted, Dryopithecus was discovered by Alfred Fontan, near Sansan in the Pyrenees region of southern France. In 1856, the find was reported to the scientific world by Edouard Lartet, who also gave it its name, which means “forest ape.” in 1868, Louis Lartet, the son of Edouard Lartet, reported on fossils of the earliest fully modern humans, discovered near Cro-Magnon in southwestern France. Recently, Cro-Magnon man has been assigned a date of 30,000–40,000 years. At the time, no fossils intermediate between Dryopithecus and Cro-Magnon man, except the Neanderthal man bones from Germany and Gibraltar, had been found (or so it appears from today’s accounts).
In general, Lyell wanted to see the presence of anatomically modern humans pushed far back in time—but not too far. There were limits: “we cannot expect to meet with human bones in the Miocene formations, where all the species and nearly all the genera of mammalia belong to types widely differing from those now living; and had some other rational being, representing man, then flourished, some signs of his existence could hardly have escaped unnoticed, in the shape of implements of stone or metal” (Lyell 1863, p. 399).
This idea links the origin of humans directly with the succession in time of mammalian species, and it would be seen today as implicitly evolutionary. However, Lyell (1863, p. 499) proposed withholding final judgement regarding human evolution until a great many fossils confirming modern humanity’s link with Dryopithecus were discovered: “At some future day, when many hundred species of extinct quadrumana [primates] may have been brought to light, the naturalist may speculate with advantage on this subject.”
Still, Lyell clearly felt we should not let the lack of such evidence prejudice us against the idea of evolution. “The opponents of the theory of transmutation sometimes argue,” he wrote, “that, if there had been a passage by variation from the lower Primates to Man, the geologist ought ere to this have detected some fossil remains of the intermediate links of the chain” (Lyell 1863, p. 435). But Lyell went on to suggest that “what we have said respecting the absence of gradational forms between the recent and Pliocene mammalia . . . may serve to show the weakness in the present state of science of any argument based on such negative evidence, especially in the case of man, since we have not yet searched those pages of the great book of nature, in which alone we have any right to expect to find records of the missing links alluded to” (1863, pp. 435–436). He believed the proper paleontological pages were to be found in Africa and the East Indies. It is there, he felt that “the discovery, in a fossil state, of extinct forms allied to the human, could be looked for” (Lyell 1863, p. 498).
Lyell’s approach was reasonable, since he advocated withholding judgement until enough evidence was gathered. However, while rejecting arguments based on a lack of evidence, he was perhaps implicitly assuming that the discovery of semihuman forms would confirm modern humanity’s descent from those forms. This is an error (and a perennial one), for the presence of a semihuman form does not preclude the contemporary or prior existence of fully human forms.
1.5 Darwin speaks
We have now seen that Huxley, Haeckel, and Lyell all wrote major works dealing with the question of human origins and that they did so before Darwin, who had deliberately held back from treating the question in The Origin of Species. Finally, in 1871 Darwin came out with his own book, Descent of Man. explaining his delay, Darwin (1871, p. 389) wrote: “during many years I collected notes on the origin or descent of man, without any intention of publishing on the subject, but rather with the determination not to publish, as I thought that I should thus only add to the prejudices against my views. It seemed to me sufficient to indicate, in the first edition of my ‘Origin of Species,’ that by this work ‘light would be thrown on the origin of man and his history;’ and this implies that man must be included with other organic beings in any general conclusion respecting his manner of appearance on this earth.”
In Descent of Man, Darwin was remarkably explicit in denying any special status for the human species. “We thus learn that man is descended from a hairy, tailed quadruped, probably arboreal in its habits, and an inhabitant of the Old World. . . . The higher mammals are probably derived from an ancient marsupial animal, and this through a long series of diversified forms, from some amphibianlike creature, and this again from some fish-like animal. In the dim obscurity of the past we can see that the early progenitor of all the vertebrata must have been an aquatic animal. . . . More like the larvae of the existing marine Ascidians than any other known form” (Darwin 1871, p. 911). It was a bold statement, yet one lacking the most convincing kind of proof—fossils of species transitional between the ancient dryopithecine apes and modern humans.
The absence of evidence of possible transitional forms may not provide a proper disproof of evolution, but one can argue that such forms are required in order to positively prove the theory. Yet aside from the Neanderthal skulls and a few other little-reported finds of modern morphology, there were no discoveries of hominid fossil remains. This fact soon became ammunition to those who were revolted by Darwin’s suggestion that humans had apelike ancestors. Where, they asked, were the fossils to prove it?
1.6 The Incompleteness of the Fossil Record
Darwin himself (1871, p. 521) felt forced to reply and sought to defend himself by appealing to the imperfection of the fossil record: “With respect to the absence of fossil remains, serving to connect man with his ape-like progenitors, no one will lay much stress on this fact who reads sir c. Lyell’s discussion (Elements of Geology 1865, pp. 583–585 and Antiquity of Man 1863, p. 145), where he shows that in all the vertebrate classes the discovery of fossil remains has been a very slow and fortuitous process. nor should it be forgotten that those regions which are the most likely to afford remains connecting man with some extinct ape-like creatures, have as yet not been searched by geologists.”
Lyell (1863, p. 146) had argued that it was not “part of the plan of nature to store up enduring records of a large number of individual plants and animals which have lived.” Rather nature tends to regularly clear her files, employing “the heat and moisture of the sun and atmosphere, the dissolving power of carbonic and other acids, the grinding teeth and gastric juices of quadrupeds, birds, reptiles, and fish, and the agency of many other invertebrata” (Lyell 1863, p. 146). Lyell also pointed out that researchers who had attempted to dredge human fossils from the sediments on the sea bottom had also been unsuccessful. He cited the attempt of the team of macAndrew and Forbes who “failed utterly in drawing up from the deep a single human bone” and found no human artifacts “on a coast line of several hundred miles in extent, where they approached within less than half a mile of a land peopled by millions of human beings” (Lyell 1863, pp. 146–147).
To the present day, the drastic incompleteness of the fossil record has remained a critical factor in paleontology. Most popular presentations of evolution give the idea that the layers of sedimentary rock offer a complete and incontrovertible record of the progressive development of life on earth. But geologists who have studied the matter have come up with some astounding findings. For example, Tjeerd H. van Andel looked at a series of sandstone and shale deposits in Wyoming, parts of which apparently were submerged in a body of water resembling our present Gulf of Mexico. The rates at which sediment is deposited in the Gulf of Mexico are known. Applying these rates to the Wyoming strata, van Andel calculated they could have been deposited in 100,000 years. Yet geologists and paleontologists agreed that the series spans a time of 6 million years. That means that 5.9 million years of strata are missing. Van Andel (1981, p. 397) stated: “We may repeat the experiment elsewhere; invariably we find that the rock record requires only a small fraction, usually 1 to 10 percent, of the available time. . . . Thus it appears that the geological record is exceedingly incomplete.”
What about the sea bottom? Shouldn’t the lack of erosional forces present on continental land masses result in a more complete record there? Van Andel (1981, p. 397) answered: “This turned out to be far from true. In the south Atlantic, for example, barely half of the history of the last 125 Myr is recorded in the sediment. It is no better in other oceans and surely worse for shallow marine and continental environments.”
This has definite implications regarding the fossil record. Van Andel (1981, p. 398) warned that “key elements of the evolutionary record may be forever out of reach.” J. Wyatt Durham, a past president of the Paleontological Society, pointed out that according to theory, about 4.1 million fossilizable marine species have existed since the Cambrian period some 600 million years ago. Yet only 93,000 fossil species have been catalogued. Durham (1967, p. 564) concluded: “Thus conservatively we now know about one out of every 44 species of invertebrates with hard parts that has existed in the marine environment since the beginning of the Cambrian. I think this ratio is unrealistically conservative; probably one out of every 100 is closer to reality.”
When we turn from marine organisms to the totality of living organisms, the situation only gets worse. David m. Raup, curator of Chicago’s Field museum, and Steven Stanley, a paleontologist at Johns Hopkins University, estimated that 982 million species have existed during the earth’s history, compared with the 130,000 known fossil species. They concluded that “only about .013 of one percent of the species that have lived during this 600 million year period have been recognized in the fossil record” (Raup and Stanley 1971, p. 11).
What does this have to do with human evolution? The standard idea is that the fossil record reveals a basic history, true in outline even though not known in every detail. But this might not at all be the case. Can we really say with complete certainty that humans of the modern type did not exist in distant bygone ages? Consider Van Andel’s point that out of 6 million years, only 100,000 may be represented by surviving strata. In the unrecorded 5.9 million years there is time for even advanced civilizations to have come and gone leaving hardly a trace.
Darwin’s appeal to the incompleteness of the fossil record served to explain the absence of evidence supporting his theory. It was, nevertheless, basically a weak argument. Admittedly, many key events in the history of life probably have gone unrecorded in the surviving strata of the earth. But although these unrecorded events might support the theory of human evolution, they might radically contradict it.
Today, however, almost without exception, modern paleoanthropologists believe that they have fulfilled the expectations of Darwin, Huxley, and Haeckel by positive discoveries of fossil human ancestors in Africa, Asia, and elsewhere. We will now give a brief summary of these discoveries, placing them within the framework of the history of life on the earth as reconstructed by paleontologists. In this summary, we shall introduce the standard system of geological dates and time divisions that we will use throughout the book.
1.7 The Geological Timetable
The story of life on earth now accepted by paleontologists can be outlined as follows. About 4.6 billion years ago the earth came into being as part of the formation of the solar system. The earliest evidences of life are fossils reputed to be of single-celled organisms. These date to 3.5 billion years ago. It is said that only single-celled organisms inhabited the earth until about 630 million years ago, when simple multicellular creatures first make their appearance in the fossil record.
Then, some 590 million years ago, there was an explosive proliferation of invertebrate marine life forms, such as trilobites. This marks the beginning of the Paleozoic era and its first subdivision, the Cambrian period. The first fish are often said to have appeared in the Ordovician period, beginning 505 million years ago, but Cambrian fish have now been reported. In the Silurian period, beginning some 438 million years ago, the first land plants entered the fossil record. We note, however, that spores and pollen from such plants have been reported from Cambrian and even Precambrian marine strata (Jacob et al. 1953, stain forth 1966, McDougall et al. 1963, Snelling 1963). In the Devonian period, which began 408 million years ago, the first amphibians came on the scene, followed by early reptiles in the carboniferous period, the beginning of which is set at about 360 million years ago. Next is the Permian period, which began some 286 million years ago and marks the end of the Paleozoic era.
The next period is the Triassic, which began some 248 million years ago and is marked by the appearance of the first mammals. In the succeeding Jurassic period, which extends from 213 million years to 144 million years ago, paleontologists note the appearance of the first birds. The Jurassic and Triassic periods, along with the following cretaceous period, are famous as the Age of the dinosaurs and are known collectively as the Mesozoic era. At the end of the cretaceous period, some 65 million years ago, the dinosaurs mysteriously died out.
Then comes the Cenozoic era. The name Cenozoic is made of two Greek words meaning “recent” and “life.” The Cenozoic is divided into seven periods: Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and finally the Holocene or most recent period, dating back 10,000–12,000 years. The dates for these periods, and the periods comprising the Paleozoic and Mesozoic eras, are given in Table 1.1. These dates are taken from A Geologic Time Scale, a recent text on radiometric dating (Harland et al. 1982).
The geological time divisions were largely formulated in the nineteenth century, on the basis of stratigraphic considerations. Initially, there was no way to assign quantitative dates to these divisions, and thus geologists referred to them qualitatively—a particular period was simply said to be earlier or later than another. In the twentieth century, scientists began to assign quantitative dates by means of radiometric methods, and they have continued to revise these dates periodically up to the present time. Thus today many roughly equivalent systems of dates are used by different geologists and paleontologists.
In general, we will use the dates in Table 1.1 throughout this book. When authors from the nineteenth century or early twentieth century assign a fossil to, say, the Miocene period, we will state that the fossil is from 5 to 25 million years old. The author in question may have had no quantitative estimate of the age of his fossil, or he may have had an estimate quite different from 5 to 25 million years. However, if the modern dates from Table 1.1 are correct for the Miocene, and the early author correctly assigned his fossil to the Miocene on the basis of stratigraphy, then it is valid for us to use the modern dates. We will do this since it helps us compare the old discovery with modern discoveries, which are generally given quantitative radiometric dates.
In some cases, the geological periods assigned to certain strata in the nineteenth century have been revised by modern geologists. For example, some Miocene strata have been reassigned to the Pliocene period. In general, whenever strata in a given locality have been identified, we have tried to look up the periods assigned to them in current geological literature. We have then given dates to these strata on the basis of the modern period assignments.
However, this method is often inadequate for assigning dates to nineteenth century Pliocene and Pleistocene sites. In recent years, dates ranging from 2.7 to 15.0 million years have been assigned to the start of the Pliocene, with many vertebrate paleontologists favoring 10–12 million years. Other scientists have used the potassium-argon method to assign a date of 4.5–6.0 million years to the start of the Pliocene, and in Table 1.1 this date is listed as 5 million years (Berggren and Van Couvering 1974).
The Pliocene-Pleistocene boundary is defined as the base of the Calabrian, a marine stratigraphic subdivision from Italy, and this is now thought to be approximately 1.8 million years old. However, for this book the terrestrial mammalian fauna associated with the Pliocene and Pleistocene are of primary importance, since evidence pertaining to ancient human beings is typically dated on the basis of associated mammalian bones. A key faunal subdivision associated with the Pliocene and Pleistocene is the Villafranchian, which is divided into early, middle, and late sections, with dates ranging from 3.5 – 4.0 million years to 1.0 –1.3 million years. Since many vertebrate paleontologists assigned the Villafranchian entirely to the Pleistocene, the starting date of the Pleistocene was sometimes given as 3.5 – 4.0 million years. At present, however, the Villafranchian is divided between the Pleistocene and Pliocene, and the basal Calabrian date of 1.8–2.0 million years is assigned to the beginning of the Pleistocene (Berggren and Van Couvering 1974).
As a result, the best way to arrive at a quantitative date for a nineteenth century site with Villafranchian (or later) fauna is to refer to modern estimates for the age of that site in years, and we have tried to do this as much as possible.
For sites with pre-Villafranchian fauna, the period will be Early Pliocene or earlier, and it is adequate for the purposes of this book to arrive at a date using Table 1.1 and the period presently assigned to the site.
In this book, we will take the modern system for granted, accepting it, for the sake of argument, as a fixed reference frame to use in studying the history of ancient humans and near humans. However, it is clear on closer examination that this reference frame is by no means fixed, and it may be that further study will reveal as much ambiguity in the evidence for its different time divisions and fossil markers as we have found in the evidence for ancient humans.
Certainly, experts in geology have sometimes expressed dissatisfaction with the established geological time divisions. For example, Edmund m. Spieker (1956, p. 1803) made the following remarks in a lecture delivered to the American Association of Petroleum Geologists: “I wonder how many of us realize that the time scale was frozen in its present form by 1840. . . . How much world geology was known in 1840? A bit of Western Europe, none too well, and a lesser fringe of eastern North America. All of Asia, Africa, South America, and most of North America were virtually unknown. How dared the pioneers assume that their scale would fit the rocks in these vast areas, by far most of the world? Only in dogmatic assumption. . . . And in many parts of the world, notably India and South America, it does not fit. But even there it was applied! The founding fathers went forth across the earth and in Procrustean fashion made it fit the sections they found, even in places where the actual evidence literally proclaimed denial. So flexible and accommodating are the ‘facts’ of geology.”
1.8 The Appearance of the Hominids
The first apelike beings appeared in the Oligocene period, which began about 38 million years ago. The first apes thought to be on the line to humans appeared in the Miocene, which extends from 5 to 25 million years ago. These include the dryopithecine ape Proconsul africanus and Ramapithecus, which is now thought to be an ancestor of the orangutan.
Then came the Pliocene period. During the Pliocene, the first hominids, or erect-walking humanlike primates, are said to appear in the fossil record. The term hominid should be distinguished from hominoid, which designates the taxonomic superfamily including apes and humans. The earliest known hominid is Australopithecus, the “southern ape,” and is dated back as far as 4 million years, in the Pliocene.
This near human, say scientists, stood between 4 and 5 feet tall and had a cranial capacity of between 300 and 600 cubic centimeters (cc). From the neck down, Australopithecus is said to have been very similar to modern humans, whereas the head displayed some apelike and some human features.
One branch of Australopithecus, known as the “gracile” or lighter branch, is thought to have given rise to Homo habilis around 2 million years ago, at the beginning of the Pleistocene period. Homo habilis appears similar to Australopithecus except that his cranial capacity is said to have been larger, between 600 and 750 cc.
Homo habilis is thought to have given rise to Homo erectus (the species that includes Java man and Peking man) around 1.5 million years ago. Homo erectus is said to have stood between 5 and 6 feet tall and had a cranial capacity varying between 700 and 1,300 cc. most paleoanthropologists now believe that from the neck down, Homo erectus was, like Australopithecus and Homo habilis, almost the same as modern humans. The forehead, however, still sloped back from behind massive brow ridges, the jaws and teeth were large, and the lower jaw lacked a chin. It is believed that Homo erectus lived in Africa, Asia, and Europe until about 200,000 years ago.
Paleoanthropologists believe that anatomically modern humans (Homo sapiens) emerged gradually from Homo erectus. Somewhere around 300,000 or 400,000 years ago the first early Homo sapiens or archaic Homo sapiens are said to have appeared. They are described as having a cranial capacity almost as large as that of modern humans, yet still manifesting to a lesser degree some of the characteristics of Homo erectus, such as the thick skull, receding forehead, and large brow ridges. Examples of this category are the finds from Swanscombe in England, Steinheim in Germany, and Fontechevade and Arago in France. Because these skulls also possess, to some degree, Neanderthal characteristics (Gowlett 1984, p. 85; Bräuer 1984, p. 328; stringer et al. 1984, p. 90), they are also classified as pre-Neanderthal types. Most authorities now postulate that both anatomically modern humans and the classic Western European Neanderthals evolved from the pre-Neanderthal or early Homo sapiens types of hominids (Spencer 1984, pp. 1– 49).
In the early part of the twentieth century, some scientists advocated the view that the Neanderthals of the last glacial period, known as the classic Western European Neanderthals, were the direct ancestors of modern human beings. They had brains larger than those of Homo sapiens sapiens. Their faces and jaws were much larger, and their foreheads were lower, sloping back from behind large brow ridges. Neanderthal remains are found in Pleistocene deposits ranging from 30,000 to 150,000 years old. However, the discovery of early Homo sapiens in deposits far older than 150,000 years effectively removed the classic Western European Neanderthals from the direct line of descent leading from Homo erectus to modern humans.
The type of human known as Cro-Magnon appeared in Europe approximately 30,000 years ago (Gowlett 1984, p. 118), and they were anatomically modern. scientists used to say that anatomically modern Homo sapiens sapiens first appeared around 40,000 years ago, but now many authorities, in light of the Border cave discoveries in south Africa, say that they appeared around 100,000 years ago (Rightmire 1984, pp. 320–321).
The cranial capacity of modern humans varies from 1,000 cc to 2,000 cc, the average being around 1,350 cc. As can be readily observed today among modern humans, there is no correlation between brain size and intelligence. There are highly intelligent people with 1,000 cc brains and morons with 2,000 cc brains. exactly where, when, or how Australopithecus gave rise to Homo habilis,
or Homo habilis gave rise to Homo erectus, or Homo erectus gave rise to modern humans is not explained in present accounts of human origins. However, one thing paleoanthropologists do say is that only anatomically modern humans came to the new World. The earlier stages of evolution, from Australopithecus on up, are all said to have taken place in the Old World. The first arrival of human beings in the new World is generally said to have occurred some 12,000 years ago, with some scientists willing to grant a Late Pleistocene date of 25,000 years.
Even today there are many gaps in the presumed record of human descent. For example, there is an almost total absence of fossils linking the Miocene apes with the Pliocene ancestors of modern apes and ancestral humans, especially within the span of time between 4 and 8 million years ago.
Perhaps it is true that fossils will someday be found that fill in the gaps. Yet, and this is extremely important, there is no reason to suppose that the fossils that turn up will be supportive of evolutionary theory. What if, for example, fossils of anatomically modern humans turned up in strata older than those in which the dryopithecine apes were found? Even if anatomically modern humans were found to have lived contemporaneously with Dryopithecus (or even a million years ago, 4 million years after the late Miocene disappearance of Dryopithecus), that would be enough to throw the current accounts of the origin of humankind completely out the window.
In fact, such evidence has already been found, but it has since been suppressed or conveniently forgotten. Much of it came to light immediately after Darwin published The Origin of Species, before which there had been no notable finds except Neanderthal man. In the first years of Darwinism, there was no clearly established story of human descent to be defended, and professional scientists made and reported many discoveries that now would never make it into the pages of any journal more academically respectable than the National Enquirer. Most of these fossils and artifacts were unearthed before the discovery by Eugene Dubois of Java man, the first protohuman hominid between Dryopithecus and modern humans.
Java man was found in Middle Pleistocene deposits generally given an age of 800,000 years. The discovery became a benchmark. Henceforth, scientists would not expect to find fossils or artifacts of anatomically modern humans in deposits of equal or greater age. If they did, they (or someone wiser) concluded that this was impossible and found some way to discredit the find as a mistake, an illusion, or a hoax. Before Java man, however, reputable nineteenth-century scientists found a number of examples of anatomically modern human skeletal remains in very ancient strata. And they also found large numbers of stone tools of various types, as well as animal bones bearing signs of human action.
1.9 Some Principles of Epistemology
Before beginning our survey of rejected and accepted paleoanthropological evidence, we shall outline a few epistemological rules that we have tried to follow. Epistemology is defined in Webster’s New World Dictionary (1978) as “the study or theory of the origin, nature, methods, and limits of knowledge.” When engaged in the study of scientific evidence, it is important to keep the “nature, methods, and limits of knowledge” in mind; otherwise one is prone to fall into a number of illusions.
One important illusion, sometimes called the illusion of “misplaced concreteness,” is that a scientific study deals directly with facts, and that scientific arguments appealing to the facts can prove statements about reality. For example, one might suppose that an argument involving facts in the form of fossil bones can prove that anatomically modern humans really did arise in Africa 100,000 years ago. Thinking this, one might strongly argue, on the basis of certain facts, that the statement “anatomically modern humans arose in Africa 100,000 years ago” represents the truth. If the facts are part of reality, and the arguments are sound, then surely the conclusion must be true. Or, at least, granting our human fallibility, we can be reasonably confident that it is true.
The problem here is that in the field of paleoanthropology the facts being considered are not directly part of reality. Indeed, if a “fact” is examined closely it is found to resolve into (1) arguments based on further “facts,” or (2) claims that someone has witnessed something at a particular time and place. Thus “facts” turn out to be networks of arguments and observational claims.
To some extent, this is true of the facts discussed in any field of science. But the facts of paleoanthropology have certain key limitations that should be pointed out. First, the observations that go into paleoanthropological facts tend to involve rare discoveries that cannot be duplicated at will. For example, some scientists in this field have built great reputations on the basis of a few famous discoveries, and others, the vast majority, have spent their whole careers without making a single significant find.
Second, once a discovery is made, key elements of the evidence are destroyed, and knowledge of these elements depends solely on the testimony of the discoverers. For example, one of the most important aspects of a fossil is its stratigraphic position. However, once the fossil is removed from the earth, the direct evidence indicating its position is destroyed, and we simply have to depend on the excavator’s testimony as to where he or she found it. Of course, one may argue that chemical or other features of the fossil may indicate its place of origin. This is true in some cases but not in others. And in making such judgements, we also have to depend on reports concerning the chemical and other physical properties of the strata in which the fossil was allegedly found.
Persons making important discoveries sometimes cannot find their way back to the sites of those discoveries. After a few years, the sites are almost inevitably destroyed, perhaps by erosion, by complete paleoanthropological excavation, or by commercial developments (involving quarrying, building construction, and so forth). Even modern excavations involving meticulous recording of details destroy the very evidence they are recording, and leave one with nothing but written testimony to back up many key assertions. And many important discoveries, even today, involve very scanty recording of key details.
Thus a person desiring to verify paleoanthropological reports will find it very difficult to gain access to the “real facts,” even if he or she is able to travel to the site of a discovery. And, of course, limitations of time and money make it impossible to personally examine more than a small percentage of the totality of important paleoanthropological sites.
A third problem is that the facts of paleoanthropology are seldom (if ever) simple. A scientist may testify that “the fossils were clearly weathering out of a certain Early Pleistocene layer.” But this apparently simple statement may depend on many observations and arguments involving geological faulting, the possibility of slumping, the presence or absence of a layer of hillwash, the presence of a refilled gully, and so on. If one consults the testimony of another person present at the site, one may find that he or she discusses many important details not mentioned by the first witness.
Different observers sometimes contradict one another, and their senses and memories are imperfect. Thus, an observer at a given site may see certain things, but miss other important things. Some of these things might be seen by other observers, but this could turn out to be impossible because the site has become inaccessible.
Then there is the problem of cheating. This can occur on the level of systematic fraud, as in the Piltdown case. As we shall see, to get to the bottom of this kind of cheating one requires the investigative abilities of a super Sherlock Holmes plus all the facilities of a modern forensic laboratory. Unfortunately, there are always strong motives for deliberate or unconscious fraud, since fame and glory await the person who succeeds in finding a human ancestor.
Cheating can also occur on the level of simply omitting to report observations that do not agree with one’s desired conclusions. As we will see in the course of this book, investigators have sometimes admitted that they have observed artifacts in certain strata, but never reported this because they did not believe the artifacts could possibly be of that age. It is very difficult to avoid this, because our senses are imperfect, and if we see something that seems impossible, then it is natural to suppose that we may be mistaken. Indeed, this may very well be the case. Thus, cheating by omitting to mention important observations can have an important effect on paleoanthropological conclusions, but it cannot be eliminated. It is simply a limitation of human nature that, unfortunately, can have a considerably deleterious impact on the empirical process.
The drawbacks of paleoanthropological facts are not limited to excavations of objects. Similar drawbacks are also found in modern chemical or radiometric dating studies. For example, a carbon 14 date might seem to involve a straightforward procedure that reliably yields a number—the age of an object. But actual dating studies often turn out to involve complex considerations regarding the identity of samples, and their history and possible contamination. They may involve the rejection of some preliminary calculated dates and the acceptance of others on the basis of complex arguments that are seldom explicitly published. Here also the facts can be complex, incomplete, and largely inaccessible.
The conclusion we draw from these limitations of paleoanthropological facts is that in this field of study we are largely limited to the comparative study of reports. Although “hard evidence” does exist in the form of fossils and artifacts in museums, most of the key evidence that gives importance to these objects exists only in written form.
Since the information conveyed by paleoanthropological reports tends to be incomplete, and since even the simplest paleoanthropological facts tend to involve complex, unresolvable issues, it is difficult to arrive at solid conclusions about reality in this field. What then can we do? We suggest that one important thing we can do is compare the quality of different reports. Although we do not have access to the real facts, we can directly study different reports and objectively compare them.
A collection of reports dealing with certain discoveries can be evaluated on the basis of the thoroughness of the reported investigation and the logic and consistency of the arguments presented. One can consider whether or not various skeptical counterarguments to a given theory have been raised and answered. Since reported observations must always be taken on faith in some respect, one can also inquire into the qualifications of the observers.
We propose that if two collections of reports appear to be equally reliable on the basis of these criteria, then they should be treated equally. Both sets might be accepted, both might be rejected, or both might be regarded as having an uncertain status. It would be wrong, however, to accept one set of reports while rejecting the other, and it would be especially wrong to accept one set as proof of a given theory while suppressing the other set, and thus rendering it inaccessible to future students.
We apply this approach to two particular sets of reports. The first set consists of reports of anomalously old artifacts and human skeletal remains, most of which were discovered in the late nineteenth and early twentieth centuries. These reports are discussed in Part I of this book. The second set consists of reports of artifacts and skeletal remains that are accepted as evidence in support of current theories of human evolution. These reports range in date from the late nineteenth century (the Pithecanthropus of Dubois) to the 1980s, and they are discussed in Part II. Due to the natural interconnections between different discoveries, some anomalous discoveries are also discussed in Part II.
Our thesis is that in spite of the various advances in paleoanthropological science in the twentieth century there is an essential equivalence in quality between these two sets of reports. We therefore suggest that it is not appropriate to accept one set and reject the other. This has serious implications for the modern theory of human evolution. If we reject the first set of reports (the anomalies) and, to be consistent, also reject the second set (evidence currently accepted), then the theory of human evolution is deprived of a good part of its observational foundation. But if we accept the first set of reports, then we must accept the existence of intelligent, toolmaking beings in geological periods as remote as the Miocene, or even the Eocene. If we accept the skeletal evidence presented in these reports, we must go further and accept the existence of anatomically modern human beings in these remote periods. This not only contradicts the modern theory of human evolution, but it also casts grave doubt on our whole picture of the evolution of mammalian life in the Cenozoic era.
In general, if A contradicts B it is not necessary to prove that A is right in order to prove that B is wrong. To discredit B, all that is required is to show that A and B are both equally well supported by arguments and evidence. Then they cancel each other out. That is the case with our two sets of reports.
In making this study, there are a number of basic features of modern geology and paleontology that we are accepting as a fixed reference framework. These are the system of geological time divisions, the modern radiometric dates for these divisions, the succession of faunal types in successive time divisions of the Cenozoic era, and the basic principles of stratigraphy.
It might be argued that if we are going to advocate a conclusion as radical as the one we just mentioned, then we might as well challenge these items as well. After all, if scientists can be completely wrong about the geological time range of human beings, why should we expect them to be right about the time ranges of various mammals?
The answer to this objection is that the various elements in our fixed reference frame may well be in need of reevaluation. However, in this study it would be impractical to delve into these matters in sufficient detail to demonstrate the specific defects that may exist in this geological and paleontological framework. Given the total body of available paleoanthropological evidence, we can only conclude that something must be seriously wrong with our current scientific picture of human evolution.
The point could be made that even if human beings existed in much earlier periods than is currently believed possible, this still does not contradict the theory of evolution. The evolution of humans could simply have taken place at earlier times. Our answer is that the material we are presenting can be interpreted in that way, and indeed it was so interpreted by most of the scientists who originally presented it. In fact, no matter what evidence is presented for the existence of human beings at a particular date, it is always possible to suppose that they evolved from lower forms at an earlier time.
It can also be said, however, that if the empirical basis for the current view of human evolution proves faulty, then the credibility of evolutionary theory in general is brought into question. After all, if the imposing empirical edifice of evolution from Australopithecus to Homo sapiens is just a house of cards, then how quick should one be to accept another elaborate evolutionary scheme?
1.10 Theories and Anomalous Evidence
We have spoken of “anomalous evidence” and “evidence accepted in support of modern theory.” in general, a piece of evidence is anomalous only in relation to a particular theory. If one could look at the world without any theoretical presuppositions (conscious or unconscious), one would see nothing anomalous. Unfortunately, one would probably experience little but a welter of meaningless sense perceptions, since it is through theoretical understanding that we give meaning to what we perceive.
In this connection a famous remark by Einstein is worth considering: “it may be heuristically useful to keep in mind what one has observed. But on principle it is quite wrong to try grounding a theory on observable quantities alone. In reality the opposite happens. It is the theory which determines what we can observe” (Brush 1974, p. 1167).
If Einstein is right, then as theories change, observations should also change. And this is indeed what we find in paleoanthropology. As we shall see, large amounts of paleoanthropological evidence were amassed in the late nineteenth and early twentieth centuries in support of a theory that humans or near humans were living in the Pliocene, Miocene, or earlier periods. This evidence was not regarded as anomalous by the scientists who introduced it, since they were contemplating theories of human origins (mainly along the lines of Darwinian evolution) that were compatible with this evidence. Then, with the development of the modern theory that humans like ourselves evolved in the Pleistocene, this evidence became highly unacceptable, and it vanished from sight.
One prominent feature in the treatment of anomalous evidence is what we could call the double standard. All paleoanthropological evidence tends to be complex and uncertain. Practically any evidence in this field can be challenged, for if nothing else, one can always raise charges of fraud. What happens in practice is that evidence agreeing with a prevailing theory tends to be treated very leniently. Even if it has grave defects, these tend to be overlooked. In contrast, evidence that goes against an accepted theory tends to be subjected to intense critical scrutiny, and it is expected to meet very high standards of proof.
This double standard is described in the following way by the archeologist George carter (1980, p. 318): “When a new idea is advanced, it necessarily challenges the previous idea. This disturbs the holders of the previous idea and threatens their security. The normal reaction is anger. The new idea is then attacked, and support of it is required to be of a high order of certainty. The greater the departure from the previous idea, the greater the degree of certainty required, so it is said. I have never been able to accept this. It assumes that the old order was established on high orders of proof, and on examination this is seldom found to be true.”
Of course, in this study the “new” ideas that we are bringing forward are actually older than the established ideas they contradict. One might say that these old ideas were properly repudiated many years ago, and it is absurd for us to resurrect them today. After all, science has advanced, and the methods we use today are far superior to those used a hundred years ago. For example, today we can date samples using nuclear physics, and the science of taphonomy has been developed to explain how materials are transformed when they are buried.
The answer to this objection is that we cannot accept a priori that the paleoanthropological studies of today are so superior in thoroughness, concept, and methodology to those of a hundred years ago. The existence of new dating methods does not rule out the validity of old stratigraphic studies. Indeed stratigraphy remains an essential tool in paleoanthropology. New methods can also create new sources of error, and some apparently new fields of study (such as taphonomy) were studied extensively in the past using different nomenclature.
The only way to really be sure of the relative value of new and old paleoanthropological reports is to undertake an actual comparative study of these reports, and that is what we attempt to do in this book. Another point, of course, is that anomalous findings are also being made today, and as we shall see, some of these involve the latest paleoanthropological techniques.
In discussing the anomalous and accepted reports in Parts I and II, we have tended to stress the merits of the anomalous reports, and we have tended to point out the deficiencies of the accepted reports. It could be argued that this indicates bias on our part. Actually, however, our objective is to show the qualitative equivalence of the two bodies of material by demonstrating that there are good reasons to accept much of the rejected material, and also good reasons to reject much of the accepted material. It should also be pointed out that we have not suppressed evidence indicating weaknesses in the anomalous findings. In fact, we extensively discuss reports that are highly critical of these findings, and give our readers the opportunity to form their own opinions.
1.11 The Phenomenon of Suppression
As George carter pointed out, some ideas or observations deviate more than others from an accepted theoretical viewpoint. If a finding is slightly anomalous, it may win acceptance after a period of controversy. If it is more anomalous, it may be studied for some time by a few scientists, while being rejected by the majority. For example, today we see that some scientists, such as Robert Jahn of Princeton University, publish parapsychological studies, while most scientists completely disregard this subject. Finally, there are some observations that so violently contradict accepted theories that they are never accepted by any scientists. These tend to be reported by scientifically uneducated people in popular books, magazines, and newspapers.
As time passes and theories change, the status of anomalous observations also changes. In some cases (as shown, for example, by the theory of continental drift), evidence once considered anomalous may later attain scientific acceptability. In other cases, evidence which was acceptable, or marginally acceptable, may become so anomalous that professional scientists will completely reject it.
This process of rejection does not usually involve careful scrutiny of the evidence by the scientists who reject it. Human time and energy are limited, and most scientists prefer to focus on positive research goals, rather than spend time scrutinizing unpopular claims. In the scientific community, the word will go out that certain findings are bogus, and this is enough to induce most scientists to avoid the rejected material.
When theories change, and a certain body of ideas and discoveries becomes unacceptable, there is generally a period of time during which prominent scientists will publish systematic attacks against the unwanted findings. (In the parlance of some scientists at the British museum, these attacks are known as “demolition jobs.”)
If the attacks are successful, then after some last attempts at rebuttal by diehard supporters, scientists will realize it is not in their best interest to defend the unwanted material or be associated with it. A shroud of silence descends over the rejected evidence, and it continues to exist only in fossilized form in the moldering pages of old scientific journals. As time passes, a few dismissive mentions may be made in occasional footnotes, and then a new generation of scientists grows up, largely unaware that the earlier evidence ever existed.
This process of suppression of evidence is illustrated by many of the anomalous paleoanthropological findings discussed in this book. This evidence now tends to be extremely obscure, and it also tends to be surrounded by a neutralizing nimbus of negative reports, themselves obscure and dating from the time when the evidence was being actively rejected. Since these reports are generally quite derogatory, they may discourage those who read them from examining the rejected evidence further.
However, the negative reports generally provide many references to earlier positive reports. When these are examined in detail, it is often found that they contain a wealth of detailed information and reasoning not adequately dealt with in the later negative critiques. Thus to properly evaluate anomalous evidence, there is no alternative to examining in detail the arguments and evidence presented in the original reports. And that is what we now propose to do.
Incised and Broken Bones: The Dawn of Deception
Intentionally cut and broken bones of animals comprise a substantial part of the evidence for human antiquity. They came under serious study in the middle of the nineteenth century and have remained the object of extensive research and analysis up to the present.
In the decades following the publication of Darwin’s The Origin of Species, many scientists found incised and broken bones indicating a human presence in the Pliocene, Miocene, and earlier periods. Opponents suggested that the marks and breaks observed on the fossil bones were caused by the action of carnivores, sharks, or geological pressure. But supporters of the discoveries offered impressive counterarguments. For example, stone tools were sometimes found along with incised bones, and experiments with these implements produced marks on fresh bone exactly resembling those found on the fossils. Scientists also employed microscopes in order to distinguish the cuts on fossil bones from those that might be made by animal or shark teeth. In many instances, the marks were located in places on the bone appropriate for specific butchering operations.
Nonetheless, reports of incised and broken bones indicating a human presence in the Pliocene and earlier are absent from the currently accepted stock of evidence. This exclusion may not, however, be warranted. From the incomplete evidence now under active consideration, scientists have concluded that humans of the modern type appeared fairly recently. But in light of the evidence covered in this chapter, the soundness of that conclusion is somewhat deceptive.
2.1 St. Prest, France (early Pleistocene or Late Pliocene)
Just above the famous cathedral town of Chartres in northwestern France, at St. Prest, in the valley of the Eure River, there are gravel pits, where, in the early nineteenth century, workmen occasionally turned up fossils. These were first reported to the scientific world in 1848 by Monsieur de Boisvillette, the engineer in charge of the local bridges and causeways. The numerous fossils, including many extinct animals such as Elephas meridionalis, Rhinoceros leptorhinus, Rhinoceros etruscus, Hippopotamus major, and a giant beaver called Trogontherium cuvieri, were judged to be characteristic of the Late Pliocene (de Mortillet1883, pp. 28–29).
A further indication of the fossils’ great antiquity was the fact that the gravels in which they were found lay at an elevation of 25 to 30 meters [82 to 98 feet] above the present level of the Eure, where an ancient river once ran in a different bed. The geological reasoning is as follows. When rivers cut valleys into a plain, the most recent gravels will normally be found near the bottom of the valley. Gravels found further up on the sides of the valley were deposited earlier by the same river, or other rivers, before the valley reached its present depth. The higher the gravels, the greater their age.
In April of 1863, Monsieur J. Desnoyers, of the French National Museum, came to St. Prest to gather fossils. From the sandy gravels he recovered part of a rhinoceros tibia, upon which he noticed a series of narrow grooves, longer and deeper than could have resulted from minor fracturing or weathering. To Desnoyers, some of the grooves appeared to have been produced by a sharp knife or blade of flint. He also observed small circular marks that could well have been made by a pointed implement (de Mortillet 1883, p. 43). Later, upon examining collections of St. Prest fossils at the museums of Chartres and the School of Mines in Paris, Desnoyers recognized upon a diverse assortment of bones the same types of marks. He then reported his findings to the French Academy of Sciences, maintaining that while some of the marks could possibly be attributed to glacial action others were definitely the work of humans.
If Desnoyers concluded correctly that the marks on many of the bones had been made by flint implements, then it would appear that human beings had been present in France before the end of the Pliocene period. One might ask, “What’s wrong with that?” In terms of our modern understanding of paleoanthropology, quite a bit is wrong. The presence at that time in Europe of beings using stone tools in a sophisticated manner would seem almost impossible. It is believed that at the end of the Pliocene, about 2 million years ago, the modern human species had not yet come into being. Only in Africa should one find primitive human ancestors, and these were limited to Australopithecus and Homo habilis, considered the first toolmaker.
At this point, some will inevitably question whether the nineteenth-century scientists were correct in assigning the St. Prest site to the Late Pliocene. The short answer to this question is a qualified yes.
As we mentioned in our discussion of the geological time periods in the previous chapter (Section 1.7), the dating of sites at the Pliocene-Pleistocene boundary remains a matter of intense controversy. Since the St. Prest site lies roughly in this period, one might expect various authorities to place it differently. And it turns out that this is in fact the case.
The American paleontologist Henry Fairfield Osborn (1910, p. 391) placed St. Prest in the Early Pleistocene. In times closer to our own, Claude Klein (1973, pp. 692–693) reviewed French opinion regarding the age of the St. Prest fauna. In 1927, Charles Deperet characterized St. Prest as Late Pliocene. G. Denizot placed St. Prest in the Cromerian interglacial stage of the Middle Pleistocene, a view he consistently maintained into the late 1960s. In 1950, P. Pinchemel referred St. Prest to the Late Pliocene. More recently, F. Boudier, in 1965, placed St. Prest in the Waalian temperate stage of the late Early Pleistocene, with a quantitative date of about 1 million years (Klein 1973, p. 736).
Others have arrived at different quantitative dates for St. Prest. Tage Nilsson (1983, p. 158) stated that two sites in the Central Massif region of France, Sainzelles and Le Coupet, yielded potassium-argon dates of 1.3–1.9 million years. Nilsson (1983, p. 158) then said: “St. Prest, near Chartres in northern France, is held to be closely related.” Nilsson considered the three sites Late Villafranchian, or Early Pleistocene.
Let us now consider some of the species that were listed as present at St. Prest. Elephas meridionalis (sometimes called Mammuthus meridionalis) is said by modern authorities ( Maglio 1973, p. 79) to have existed in Europe from about 1.2 million to 3.5 million years ago. Osborn (1910, p. 313) places Rhinoceros (Dicerorhinus) leptorhinus in the Plaisancian (or Piacenzian) age of the Pliocene. Osborn placed the Plaisancian age in the Early Pliocene, but Romer (1966, p. 334) places the Plaisancian in the Late Pliocene. Rhinoceros (Dicerorhinus) etruscus, according to Nilsson (1983, p. 475), occurs in Europe from the Villafranchian, which begins in the Late Pliocene, to the early Middle Pleistocene. But Savage and Russell (1983, p. 339) list occurrences of Dicerorhinus etruscus as early as the Ruscinian age of the Early Pliocene. According to Osborn (1910, p. 313), Hippopotamus major, a larger version of the modern hippopotamus, is found in the Late Pliocene and throughout the Pleistocene in Europe. Hippopotamus major is sometimes referred to as Hippopotamus amphibius antiquus. This species is listed by Savage and Russell (1983, p. 351) as part of the Pliocene Villafranchian fauna of Europe. Trogontherium cuvieri, the giant extinct beaver, is found in Pliocene faunal lists (Savage and Russell 1983, p. 352) and persisted until the Mosbachian age of the early Middle Pleistocene (Osborn 1910, p. 403). Thus all the above species were in existence during the Pliocene period.
Add it all up, and it can be seen that a Late Pliocene date for St. Prest is not out of the question. And, as noted previously, some twentieth-century scientists (Pinchemel and Deperet) have in fact assigned St. Prest to this period. That would place toolmaking hominids in Europe at over 2 million years ago.
How recent could St. Prest possibly be? The presence of Elephas meridionalis, which survived in Europe until 1.2 million years ago (Maglio 1973, p. 79) would appear to impose a late Early Pleistocene limit. The potassiumargon dates of 1.3–1.9 million years for French sites having a fauna similar to that of St. Prest (Nilsson 1983, p. 158) offer another guidepost. Kurtén (1968, p. 24), like Boudier (1965), assigns St. Prest to the Waalian temperate stage of the Early Pleistocene. Some authorities place the Waalian stage at about 1.1–1.2 million years (Nilsson 1983, p. 144). But Senéze, a French site tentatively attributed to the Waalian temperate stage, is estimated to be about 1.6 million years old (Nilsson 1983, p. 158). From all this, one could conclude that the St. Prest site, at the more recent end of its probable date range, might be just 1.2–1.6 million years old. Even at this date, incised bones would still be anomalous. The oldest undisputed evidence for the presence of Homo erectus in Europe dates back only about 700,000 years (Gowlett 1984, p. 76). Also, the oldest occurrences of Homo erectus in Africa have dates of about 1.5 million years.
Even in the nineteenth century, Desnoyers’s discoveries of incised bones at St. Prest provoked controversy. Professor Bayle, a paleontologist at the School of Mines, responded to Desnoyers’s report by claiming that it was he, with his own instruments, who had incised and otherwise marked the bones of St. Prest during the process of cleaning them. Dr. Eugene Robert accepted this explanation and communicated it to the French Academy of Sciences.
In response, Desnoyers (1863) protested that his careful scientific presentation had been attacked by means of a brief rumorlike report, submitted without any credible evidence. To his accusers, Desnoyers went on to reply, in a paper published in the proceedings of the French Academy of Sciences, that the bones of St. Prest, found in sand, did not require metal instruments in order to be cleaned. Furthermore, the grooves and other markings were visible on bones that had not needed any kind of cleaning whatsoever. Perhaps the professor of paleontology at the School of Mines, Dr. Bayle, truly had been sufficiently clumsy to have extensively damaged the valuable bones under his care. But Desnoyers did not believe anyone could say the same of the many capable and careful collectors who also had specimens of fossil bones from St. Prest bearing the exact same striations and incisions. In the words of Desnoyers (1863, p. 1201): “Let us admit, against all probability, that the memoir of the preparator and conservator of the collection is true, and all the bones of St. Prest in his possession have been subjected to the kind of alteration to which he pleads guilty. Very well. That assertion itself serves to demonstrate the action of the hand of man on all the other bones from the same locality, which, fortunately, have been preserved in other collections, from dangerous influences. The marks on them are incontestably primitive, and are completely identical to those produced by the chisels and burins of the functionary of the School of Mines.”
Desnoyers (1863, p. 1201) was further annoyed that persons who had never even seen the bones claimed that the impressions on them were made by the tools of the workmen in the St. Prest sand pits. He pointed out that this supposition is clearly disproved by the fact that the grooves were covered with the same magnesium deposits and dendrites found on other sections of the bone. Dendrites are crystalline mineral deposits that form branching treelike patterns. If the cuts on the fossil bones had been made by the tools of modern excavators or museum employees, the dendrites would have been scraped away. In some cases, the grooves and marks were still tightly filled with compacted sand from the deposits in which they were discovered.
Desnoyers (1863, p. 1201) suggested that doubters examine the actual specimens: “One would see that the incisions, which furrow the bones across their width and cut their edges, are frequently crossed by the longitudinal cracks resulting from dessication. These cracks were unquestionably produced after the marks made when the bone was fresh; they were produced during the course of fossilization. The distinct characteristics of these two kinds of markings are proof that the one is older than the other.”
Recent tool marks probably would have cut through the dessication markings in recognizable fashion, erasing the lighter and shallower cracks. Desnoyers’s careful analysis foreshadows the modern discipline of taphonomy, the scientific study of the changes undergone by bone and other objects in the course of entombment and fossilization.
About one of his finds, Desnoyers (1863, p. 1201) noted, “One would see on the horn of a giant deer a large incision at the base, an incision difficult to distinguish from those found on the horns of deer from caverns of later geological eras.” In other words, the incision on the deer horn was placed appropriately for a human cut mark.
The prominent British geologist Charles Lyell agreed that the St. Prest gravel beds were of Pliocene age. He observed, however, that among the fauna was the large extinct beaver, Trogontherium, and asked how one could be certain it was not the teeth of this animal that produced the marks on the fossil bones (Lyell 1863, appendix p. 4). Gabriel de Mortillet, professor of prehistoric anthropology at the École d’Anthropologie in Paris, stated in his book Le Préhistorique (1883, p. 45) that Lyell’s supposition was inadmissible because the marks on the bones of St. Prest were not at all of the character of those of a rodent’s teeth. In particular, they were too narrow to have been made by the strong and powerful incisors of Trogontherium.
De Mortillet had his own ideas about the cause of the marks on the fossil bones of St. Prest. Some authorities had suggested glaciers had been responsible for the markings. But de Mortillet said that glaciers had not reached that particular region of France. Modern authorities (Nilsson 1983, p. 169) agree on this point—the extreme southern limit of the North European glaciation passed through the Netherlands and Central Germany. De Mortillet also rejected human action as the cause of the marks on the bones.
The key to understanding the marks, according to de Mortillet, could be found in the statement by Desnoyers that they appeared to have been made by a sharp blade of flint. According to de Mortillet (1883, pp. 45–46), that was true, only the flint, instead of being moved by the hand of man, had been moved by natural force—a very strong underground pressure that caused the sharp flints to slide across the bones with force sufficient to cut them. As evidence, de Mortillet cited the fact that he had observed flints from the St. Prest gravels and elsewhere that displayed on their surfaces deep scratches. At this point it should be mentioned that in Le Préhistorique de Mortillet rejected every single one of the many discoveries of incised bones made up to that time, almost always offering the same explanation—that the marks were caused by sharp stones moved by subterranean geological pressures.
But in the case of the St. Prest bones, Desnoyers (1863, p. 1201) responded to de Mortillet’s objections, observing: “many of the incisions have been worn by later rubbing, resulting from transport or movement of the bones in the midst of the sands and gravels. The resulting markings are of an essentially different character than the original marks and striations, and offer superabundant proof of their different ages.” In other words, marks from subterranean pressure may indeed be found upon the bones, but, according to Desnoyers, they can be clearly distinguished from the earlier marks attributed to human action.
So who was right, Desnoyers or de Mortillet? Some authorities believed the question could be settled if it could be demonstrated that the gravels of St. Prest contained flint tools that were definitely of human manufacture. This same demand—for the tools that made the marks—is often made today in cases of anomalous discoveries of incised bones (Section 2.3). The Abbé Bourgeois, a clergyman who had also earned a reputation as a distinguished paleontologist, carefully searched the strata at St. Prest for such evidence. By his patient research he eventually found a number of flints that he believed were genuine tools and made them the subject of a report to the Academy of Sciences in January 1867 (de Mortillet 1883, p. 46). Even this did not satisfy de Mortillet (1883, pp. 46–47), who said of the flints discovered by Bourgeois at St. Prest: “Many others that he found there, and which are now deposited in the collection of the School of Anthropology, do not have conclusive traces of human work. The slidings and pressures that resulted in striations on the surfaces of the flints have also left on their sharp edges a number of chips that greatly resemble retouching by humans. This is what deceived Bourgeois. In effect, of the flints discovered at St. Prest, many present a false appearance of having been worked.”
It appears that in our attempt to answer one question, the nature of cut marks on bones, we have stumbled upon another, the question of how to recognize human workmanship on flints and other stone objects. This latter question shall be fully treated in the next chapter. For now we shall simply note that judgements about what constitutes a stone tool are a matter of considerable controversy even to this day. It is, therefore, quite definitely possible to find reasons to question de Mortillet’s rejection of the flints found by Bourgeois. Certainly, the bare observation that some of the flints collected by Bourgeois did not, in de Mortillet’s opinion, show signs of human work does not change the fact that others, however few, did in fact show such signs. And the presence of stone tools at St. Prest would satisfy a key demand for the verification of intentional cuts on fossil bones found there.
The famous American paleontologist Henry Fairfield Osborn (1910, p. 399) made these interesting remarks in connection with the presence of stone tools at St. Prest: “the earliest traces of man in beds of this age [Early Pleistocene by his estimation] were the incised bones discovered by Desnoyers at St. Prest near Chartres in 1863. Doubt as to the artificial character of these incisions has been removed by the recent explorations of Laville and Rutot, which resulted in the discovery of eolithic flints, fully confirming the discoveries of the Abbé Bourgeois in these deposits in 1867.”
So as far as the discoveries at St. Prest are concerned, it should now be apparent that we are dealing with paleontological problems that cannot be quickly or easily resolved. Certainly there is not sufficient reason to categorically reject these bones as evidence for a human presence in the Pliocene. This might lead one to wonder why the St. Prest fossils, and others like them, are almost never mentioned in textbooks on human evolution, except in rare cases of brief mocking footnotes of dismissal. Is it really because the evidence is clearly inadmissible?
Or is, perhaps, the omission or summary rejection more related to the fact that the potential Late Pliocene antiquity of the objects is so much at odds with the standard account of human origins? In theory, scientists proclaim themselves ready to follow the facts wherever they might lead. But in practice, the social mechanisms of the scientific community set limits beyond which its members in good standing may cross only at their peril. When eminent authorities announce their rejection of certain categories of evidence, others hesitate to mention similar evidence out of fear of ridicule. Thus anomalous evidence gradually slides from disrepute into complete oblivion.
Along these lines, Armand de Quatrefages, a member of the French Academy of Sciences and a professor at the Museum of Natural History in Paris, wrote in his book Hommes Fossiles et Hommes Sauvages (1884, p. 90): “The objections made to the existence of humans in the Pliocene and Miocene periods seem to habitually be more related to theoretical considerations than to direct observation.” De Quatrefages (1884, p. 91) further stated: “The existence of man in the Secondary epoch is not at all contrary to the principles of science, and the same is true of Tertiary man.”
This is quite a shocking statement, considering that the most recent Secondary period is the Cretaceous, which ended approximately 65 million years ago. Supposedly, only very small and primitive mammals existed in the Cretaceous, dodging the last of the dinosaurs. Evidence for human beings in the Cretaceous would most certainly cast a great thundering cloud of doubt over Darwin’s seemingly invincible hypothesis. But for now, our focus is on the more recent Tertiary epoch. Even if anatomically modern human beings were found to have existed in the latest Pliocene, at a mere 2 million years ago, that would still call into question the evolutionary picture of human origins.
In Hommes Fossiles et Hommes Sauvages, de Quatrefages gave a summary of the evidence for his assertions about humans existing in the very distant past and then stated (1884, p. 96): “The preceding historical samples are incomplete and abbreviated. But they suffice, I believe, to make comprehensible that the conviction, agreed upon by many modern scientists of diverse disciplines, relative to the existence of Tertiary man, is not formed lightly but is the result of serious and repeated study.”
Concerning the presence of ancient man at St. Prest, de Quatrefages (1884, pp. 89–90) wrote: “Mr. Desnoyers has affirmed his existence, based on the examination of incisions manifestly intentional found on the bones of Elephas meridionalis and other great mammals of the same age. This discovery was greatly contested, by among others Lyell, who declared he was not able to accept that the incisions on the bones were demonstrably the work of man until he could be shown the instruments that did it. The Abbé Bourgeois responded to this desire. But 20 years later, de Mortillet, in opposing all the results of this research, simply raises objections which when made the object of attentive study turn out to have little foundation.”
Elsewhere in Hommes Fossiles et Hommes Sauvages, de Quatrefages (1884, p. 17) succinctly reaffirmed the evidence for the presence of humans in the Pliocene at St. Prest: “The researches of Mr. Desnoyers and the Abbé Bourgeois do not leave any doubt in this regard. Mr. Desnoyers first discovered in 1863, on bones found in the gravel pits of St. Prest, near Chartres, imprints that he did not hesitate to report as being made by the action of flint implements in the hands of human beings. A little later, the Abbé Bourgeois confirmed and completed this important discovery when he found in the same place the worked flints that had made the incisions on the bones of Elephas meridionalis, Rhinoceros leptorhinus, and other animals. I have examined at leisure the bones studied by Desnoyers, as well as the scrapers, borers, lance points, and arrowheads collected by the Abbé Bourgeois. From the start, I have had little doubt, and everything has been confirming that first impression. Thus man lived on the globe at the end of the Tertiary era. And he left traces of his industry; he had at this time both arms and tools. The honor of the first recognition of this fact, so little in accord with all that was believed only a short time ago, goes incontestably to Mr. Desnoyers.”
Here it should be noted that it would of course be possible to more briefly summarize and paraphrase reports such as these. There are two reasons for not doing so. The first is that paleoanthropological evidence mainly exists in the form of reports, some primary and others secondary. Very few individuals, even experts in the field, have the opportunity to engage in firsthand inspection of the fossils themselves, scattered in collections around the world. Even if one is able to do so, one is still not able to be sure about the exact circumstances of the discovery. This is critical, because the interpretation of the significance of a fossil depends as much on the exact position in which it was found as on the fossil itself. In most cases, for all investigators except the original discoverers, the real evidence is the reports themselves, which give the details of the discovery, and we shall therefore take the trouble to include many selections from such reports, the exact wording of which reveals much. Contemporary discussions of these original reports, both those which are positive and those which are negative, are also illuminating.
A second consideration is that the particular reports referred to in this chapter are extremely difficult to obtain. Almost no reference to them will be found in modern textbooks. Most of them come from rare nineteenth-century paleontological and anthropological books and journals, the majority in languages other than English. This being the case, translated excerpts of the original reports have been judged preferable to paraphrases and footnotes, and will serve as a unique introduction to a vast store of buried evidence.
A final consideration is that proponents of evolutionary theory often accuse authors who arrive at nonevolutionary conclusions of “quoting out of context.” It therefore becomes necessary to quote at length, in order to supply the needed context.
The controversy over the St. Prest finds was noted by S. Laing, a popular British nonfiction author of the late nineteenth century, whose well-researched books on scientific subjects, intended for the general public, reached a wide audience. After discussing the site at St. Prest, Laing (1893, p. 113) stated: “In these older gravels have been found stone implements, and bones of the Elephas Meridionalis with incisions evidently made by a flint knife worked by a human hand. This was disputed as long as possible, but Quatrefages, a very cautious and competent authority, states in his latest work, published in 1887, that it is now established beyond the possibility of doubt.”
2.2 A Modern example: Old Crow River, Canada (Late Pleistocene)
Before moving on to further examples of nineteenth-century discoveries that challenge modern ideas about human origins, let us consider a more recent investigation of intentionally modified bones. One of the most controversial questions confronting New World paleoanthropology is determining the time at which humans entered North America. The standard view is that bands of Asian hunter-gatherers crossed over the Bering land bridge about 12,000 years ago. Some authorities are willing to extend the date to about 30,000 years ago, while an increasing minority are reporting evidence for a human presence in the Americas at far earlier dates in the Pleistocene. We shall examine this question in greater detail in coming chapters (Sections 3.8, 4.8, 5.1, 5.2, 5.4, and 5.5). For now, however, we want only to consider the fossil bones uncovered at Old Crow River in the northern Yukon territory as a contemporary example of the type of evidence dealt with in this chapter.
In the 1970s, Richard E. Morlan of the Archeological Survey of Canada and the Canadian National Museum of Man, conducted studies of modified bones from the Old Crow River sites. Morlan concluded that many bones and antlers exhibited signs of intentional human work executed before the bones had become fossilized. The bones, which had undergone river transport, were recovered from an Early Wisconsin glacial floodplain dated at 80,000 years b.p. (before present).
But R. M. Thorson and R. D. Guthrie (1984) published a taphonomic study showing that the action of river ice could have caused the alterations that suggested human work to Morlan. Thorson and Guthrie performed experiments in which large blocks of ice containing bones frozen within them were dragged behind trucks over various surfaces, reproducing the effect of river ice scraping against rocks and gravels. In a 1986 reappraisal of his previous work, Morlan, considering the taphonomic experiments of Thorson and Guthrie, admitted “the observed effects are impressive for the hazards they might pose to recognition of artificial alterations among redeposited fossils.” He went on to note: “However some critical variables probably were not simulated adequately (e.g., texture and hardness of the substrate, buoyancy of the ice block), and it is noteworthy that many of the experimental bones are more profoundly altered than those recovered from natural environments. Certainly these experiments have not shown that all the altered fossils from Old Crow Basin can be attributed to river icing and breakup” (Morlan 1986, p. 29).
Nevertheless, Morlan did in fact back away, in almost all cases, from his earlier assertions that the bones he had collected had been modified by human agency. He gave alternate explanations, such as the river ice hypothesis, but cautioned: “The alternate interpretations do not prove that humans were not present in Early Wisconsinan time, but they show that such ancient presence of people cannot be demonstrated on the basis of evidence gathered thus far” (Morlan 1986, p. 27). He went on to say: “This conclusion differs from earlier statements, but it is not necessarily a retraction of those statements. I have definitely changed my mind about some of my earlier interpretations, but in most cases I am simply trying to enlarge our conceptual framework and to stimulate further observations and discussions” (Morlan 1986, pp. 28–29).
But even though Morlan recanted his previous assertions of human work on 30 bone specimens, he believed four others still bore signs of being definite human artifacts. At Johnson Creek, near Old Crow valley, he found a “freshfractured Bison sp. radius” in situ. The radius is one of the long bones of the lower forelimb. “Although it is not out of the question that the bison bone was broken by carnivores,” stated Morlan (1986, p. 36), “its massive size and micro-relief features indicative of dynamic fracture suggest that it was broken by man. The enclosing matrix of organic silt is suggestive of a thaw-lake deposit and yields a date of >37,000 b.p.”
At another locality, Morlan found two large mammal long bones and a bison rib, all three bearing incisions. Morlan (1986, p. 36) stated about these three bones and the bison radius discussed in the previous paragraph: “The cuts and scrapes . . . are indistinguishable from those made by stone tools during butchering and defleshing of an animal carcass. These four specimens comprise the most formidable barrier to a global dismissal of our supposed Early Wisconsinan archaeological record.”
Morlan (1986, p. 36) then added: “While this paper was in press . . . two cut bones . . . were sent to Dr. Pat Shipman, Johns Hopkins University, for examination under the scanning electron microscope. The marks were examined with reference to a collection of more than 1000 documented marks on bones, and the provenience [source] of the specimens was not made known until after the marks had been identified. The surface of the large mammal long bone fragment is damaged and difficult to evaluate, but Dr. Shipman positively identified the mark on the Bison rib as a tool mark.” Morlan (1986, p. 28) noted that stone implements have been found in the Old Crow River area and in nearby uplands, but not in direct association with bones.
What this all means is that the bones of St. Prest, and others like them, cannot be so easily dismissed. Evidence of the same type is still considered important today, and the methods of analysis are almost identical to those practiced in the nineteenth century. De Quatrefages and other scientists of that era compared specimens of cut bone with bones bearing undisputed signs of human workmanship. They also performed experiments on fresh bone. Like modern students of taphonomy, they gave detailed consideration to the changes that bones would undergo during the process of entombment and fossilization. They examined bones with a microscope. It should be noted that an electron microscope is not required for such study. A modern authority, John Gowlett (1984, p. 53), said: “Under a microscope, marks made by man are distinguishable in various ways from those made by carnivores. Dr. Henry Bunn (University of California) observed through an optical microscope at low magnification that stone tools leave V-shaped cuts, which are much narrower than rodent gnawing marks.”
As the Old Crow River case clearly shows, modern scientists use methods not much different from those practiced in the nineteenth century. We can just picture Thorson and Guthrie, in previous nineteenth-century incarnations, driving a horsedrawn cart, rather than a truck, and dragging behind them a big block of ice filled with bones over a rough gravel road in northern France, trying to prove the bones of St. Prest were marked by natural forces. Amusing as the image may appear, this is the type of technologically unsophisticated yet important work that still goes into resolving questions about incised bones. But as Morlan’s study shows, all questions about the Old Crow bones have not been clearly decided one way or another. He changed his mind about some of his specimens, but remained convinced about others. This ambiguity and inconclusiveness is typical of the empirical approach to such evidence.
In addition to debating whether or not the cut marks on the Old Crow bones were made by stone tools or natural forces, scientists were concerned about the age of the bones. If the bones were seen as bearing signs of human work and if they were also dated to the Early Wisconsin period, that would challenge the date for the earliest entry of humans into North America. The view now dominant is that Siberian hunters crossed the Bering Strait land bridge in the latest Pleistocene and passed through an ice-free corridor into what is now the United States about 12,000 years ago. Nevertheless, as we shall see throughout this book, there is a lot of controversial, hotly debated evidence showing that human beings were present in the Americas far before 12,000 years ago. Those scientists favoring the 12,000-year date tend to believe the marks on the Old Crow bones were caused by geological action of some kind, even though the marks have in some cases been judged identical to those caused by stone tools. This is something we shall encounter again and again. Similarly, preconceptions about the relatively recent origin of anatomically modern humans often influence scientists to reject evidence that they would otherwise take as proof of a human presence.
2.3 The Anza-Borrego Desert, California (Middle Pleistocene)
Another recent example of incised bones like those found at St. Prest, again related to the presence of humans in the New World, is a discovery made by George Miller, curator of the Imperial Valley College Museum in El Centro, California. Miller, who died in 1989, reported that six mammoth bones excavated from the Anza-Borrego Desert bear scratches of the kind produced by stone tools. Uranium isotope dating carried out by the U.S. Geological Survey indicated that the bones are at least 300,000 years old, and paleo-magnetic dating and volcanic ash samples indicated an age of some 750,000 years (Graham 1988).
One established scholar said that Miller’s claim is “as reasonable as the Loch Ness Monster or a living mammoth in Siberia,” while Miller countered that “these people don’t want to see man here because their careers would go down the drain” (Graham 1988). Here, perhaps, we see preconceptions influencing the established scholar to reject evidence which, if given a more suitably recent date, he might have accepted.
The incised mammoth bones from the Anza-Borrego Desert came up in a conversation we had with Thomas Deméré, a paleontologist at the San Diego Natural History Museum (May 31, 1990). Deméré said he was by nature skeptical of claims such as those made by Miller. He called into question the professionalism with which the bones had been excavated, and pointed out that no stone tools had been found along with the fossils. Furthermore, Deméré suggested that it was very unlikely that anything about the find would ever be published in a scientific journal, because the referees who review articles probably would not pass it. We later learned from Julie Parks, the present curator of George Miller’s specimens, that Deméré had never inspected the fossils or visited the site of discovery, although he had been invited to do so (Parks, personal communication, June 1, 1990).
As of June 1990, the Anza-Borrego mammoth bones were still under study. Deposits of sandy matrix were being painstakingly removed from the incisions on the bones, so that the incisions could be examined by a scanning electron microscope. Hopefully, inspection of the minute striations on the surfaces of the cuts under high magnification will confirm whether or not they are characteristic of stone tools. Parks (personal communication, June 1, 1990) said that one incision apparently continues from one of the fossil bones to another bone that would have been located next to it when the mammoth skeleton was articulated. This is suggestive of a butchering mark. Accidental marks resulting from movement of the bones in the earth after the skeleton had broken up probably would not continue from one bone to another in this fashion.
The lesson to be learned from the marked bones found at Old Crow River and in the Anza-Borrego Desert is this: the marked bones of St. Prest and others like them discovered in the nineteenth century should be kept in the active file of paleoanthropological evidence. Even today, scientists are not always able to immediately determine whether or not marks on bones were made by natural forces, animals, or humans. Much careful study and analysis is required to arrive at a conclusion, and even then not all experts will agree. Therefore the marked bones discussed in this chapter and the reports about them should be seriously examined, and be available for reexamination. If fossils do not pass the test of a certain investigator or school of investigators at a particular point in time, they should not be cast into the outer darkness, so that later researchers will not even know they exist. Rather they should be placed in a category of disputed evidence. In that way, in the event of improvements in the methods of analysis or changes in theoretical constructs of human prehistory, the evidence will be available for further study. Who knows? In the future, new pieces to the puzzle of human origins may give new meaning to old pieces that previously did not quite fit.
2.4 Val D’arno, Italy (early Pleistocene or late Pliocene)
Specimens incised in a manner similar to those of St. Prest were found by Desnoyers in a collection of bones gathered from the valley of the Arno River (Val d’Arno) in Italy. The grooved bones were from the same types of animals found at St. Prest—including Elephas meridionalis and Rhinoceros etruscus. They were attributed to the Late Pliocene stage called the Astian (de Mortillet 1883, p. 47). This would yield a date of 2.0–2.5 million years. Some authorities (Harland et al. 1982, p. 110) put the Astian in the Middle Pliocene, at 3– 4 million years ago.
Modern scientists divide the fauna from the Val d’Arno into two groups— the Upper Valdarno and Lower Valdarno. The Upper Valdarno is assigned to the Late Villafranchian, which is given a quantitative date of 1.0–1.7 million years (Nilsson 1983, pp. 308–309). The Lower Valdarno is placed in the Early Villafranchian, or Late Pliocene, at around 2.0–2.5 million years ago (Nilsson 1983, pp. 308–309).
It is not clear to which group the incised bones reported by Desnoyers belong. But the fact that de Mortillet referred them to the Astian stage of the Late Pliocene seems to indicate that they might be assigned to the Lower Valdarno. On faunal grounds this would not be out of the question. We know that Elephas meridionalis occurs in the Lower Valdarno (Maglio 1973, p. 56). As mentioned in our discussion of St. Prest, Rhinoceros (Dicerorhinus) etruscus is reported in the Late Pliocene (Nilsson 1983, p. 475) in Europe, and even as far back as the Early Pliocene (Savage and Russell 1983, p. 339). De Mortillet listed Equus arnensis as present at Val d’Arno. Equus is typical of Pleistocene faunal assemblages, but examples of Equus are known from the Early Villafranchian (Kurtén 1968, p. 147), which is generally thought to extend into the Late Pliocene.
2.5 San Giovanni, Italy (late Pliocene)
In addition, grooved bones also were discovered in other parts of Italy. On September 20, 1865, at the meeting of the Italian Society of Natural Sciences at Spezzia, Professor Ramorino presented bones of extinct species of red deer and rhinoceros bearing what he believed were human incisions (de Mortillet 1883, pp. 47–48). These specimens were found at San Giovanni, in the vicinity of Siena, and like the Val d’Arno bones were said to be from the Astian stage of the Pliocene period. De Mortillet (1883, p. 48), not deviating from his standard negative opinion, stated that he thought the marks were most probably made by the tools of the workers who extracted the bones.
2.6 Rhinoceros of Billy, France (Middle Miocene)
On April 13, 1868, A. Laussedat informed the French Academy of Sciences that P. Bertrand had sent him two fragments of a lower jaw of a rhinoceros. They were from a pit near Billy, France. One of the fragments had four very deep grooves on it. These grooves, situated on the lower part of the bone, were approximately parallel and inclined at a 40-degree angle to the longitudinal axis of the bone. They were 1–2 centimeters (a half inch or so) in length, and the deepest was 6 mm (a quarter inch) in depth (Laussedat 1868, p. 752). According to Laussedat, the cut marks appeared in cross section like those made by a hatchet on a piece of hard wood. And so he thought the marks had been made in the same way, that is, with a handheld stone chopping instrument, when the bone was fresh. That indicated to Laussedat (1868, p. 753) that humans had been contemporary with the fossil rhino in a geologically remote time.
Just how remote is shown by the fact that the jawbone was found in a calcareous sand stratum at a depth of 8 meters (26 feet), in between other strata of the Mayencian age of the Middle Miocene. Furthermore, the incised jawbone was from a species, Rhinoceros pleuroceros, judged by Laussedat to be characteristic of the Early Miocene. According to modern authorities (Savage and Russell 1983, p. 214), Rhinoceros (Dicerorhinus) pleuroceros occurs in the Agenian land mammal age of the Early Miocene.
At the meeting of the Academy of Sciences, Mr. Hebert asked if one could be sure of the authenticity of the incisions on the fossil. Edouard Lartet responded with a demonstration that the marks, the surfaces of which had the same appearance as the other parts of the bone, indeed dated from the time of burial (de Mortillet 1883, p. 49).
By what agency were the marks produced? De Mortillet (1883, p. 50) rejected straightaway the idea of gnawing by carnivores, because the incisions did not display the appropriate characteristics. Animal gnawing tends to be accompanied by significant destruction of the bone, whereas the rhinoceros jawbone from Billy bore only the four rather clear incisions. Were they produced by human beings? De Mortillet thought not. The imprints of a stone edge used as a saw are easily recognizable, and there were no traces of sawing on the bone. Because of their irregular edges, cutting instruments of stone generally leave small striations along the longitudinal axis of the V-shaped groove produced. But on the markings of the Billy fossil the striations were said to be transverse to this axis, i.e., running from the top of the cut, vertically down to the bottom of the groove. Furthermore, the marks on the jawbone were wider and deeper than might be expected from the action of a thin stone blade drawn across the bone.
De Mortillet thought the marks were not produced by a stone chopping instrument as proposed by Laussedat. The blow of a stone handaxe, according to de Mortillet, leaves an imprint with rounded sides. The marks on the jawbone of Billy, however, were straight-sided, and could not, in the opinion of de Mortillet, have been the result of a stone hatchet blow. Furthermore, he noted that the mark of the blow of a hatchet is distinguished by a surface clean and sharp on the side hit by the blade, and abrupt and rough on the side from which the splinter of bone separates. In the imprints on the jaw of Billy, this feature was, said de Mortillet, absent (1883, p. 50).
What then had been the cause? De Mortillet, sticking to his usual explanation, wrote in Le Préhistorique (1883, pp. 50 –51): “They are simply geological impressions. All geologists know that there exist in many terrains, especially Miocene, rocks that have profound impressions on them. The cause is not easily recognized, but the fact that it has been observed is incontestable. There is a great similarity between the marks on some of these rocks and those on the jaw of Billy. I have collected at Tavel (Gard), and given to the museum of Saint-Germain, a quartzite rock, a very hard rock, bearing marks completely analogous to those on the specimen presented by Mr. Laussedat. On examining with care and at length this bone, one notices on one of the extremities a small impression produced by crushing. There is no removal of material, simply compression. This impression, which is of the same aspect as the other marks on the bone, is their contemporary and serves to explain them.”
About marks on stones from Miocene formations, de Mortillet, as mentioned above, admitted that “the cause is not easily recognized.” It is known that glaciers can groove bedrock, but this phenomenon is not applicable to grooved stones (or fossil bones) from preglacial Miocene formations. De Mortillet mentioned a grooved piece of quartzite. But quartzite is a very hard rock (7 on the Mohs scale of hardness, with talc at 1 and diamond at 10). It would thus require a harder mineral, which de Mortillet did not name, and extreme pressure, which de Mortillet did not explain, to mark quartzite with deep grooves. One must also consider the possibility that grooves in quartzite might be caused by chemical corrosion and recrystallization rather than cutting.
It is apparent that neither we nor de Mortillet know for certain what produced the grooves in the quartzite rock he found at Tavel. But it is probably not the same agency that would produce grooves on bone, a very different material, found in a freshwater deposit of calcified sand (de Mortillet 1883, p. 49). In essence, we find de Mortillet proposing that we should accept a completely unknown geological mechanism to explain the marks on the rhinoceros jaw of Billy, in preference to the known mechanism of human action. Although de Mortillet may be right, he offers insufficient evidence to justify his view.
Another factor to consider is the character and placement of the marks on the rhinoceros jaw of Billy. A highly regarded modern authority on cut bones is Lewis R. Binford, an anthropologist from the University of New Mexico at Albuquerque. In Bones: Ancient Men and Modern Myths, a comprehensive study of incised faunal remains, Binford pointed out that a key element in distinguishing human incisions from others is the exact placement of the marks. Extensive research has shown that in almost all cultures, ancient and modern, butchering marks tend to occur, though with some degree of variation, on specific bones and in specific locations on those bones, as dictated by the anatomy of the animal. For example, Binford (1981, p. 101) stated: “Marks on the mandible [lower jaw] tend to be slightly oblique incised marks on the inside of the mandible generally opposite the M2 tooth [second molar]. The marks are believed to originate from the underside of the mandible and to be related to the severing of the mylohyoid muscle during the removal of the tongue.” The marks described by Laussedat appear to conform to this general description, but because no drawing or photo accompanied the available reports on the Billy jawbone, this remains to be more exactly confirmed.
The marks on the jawbone of Billy, which Laussedat described as a group of short parallel cuts, also appear to be consistent with the type of pattern that might be made by stone implements. According to Binford (1981, p. 105): “Most of the cut marks made on bones with metal tools are almost hairline in size. . . . the marks are generally long, resulting from cuts running across tissue for considerable distances. Cutting with stone tools requires a much less continuous action, more of a series of short parallel strokes. . . . Marks from stone tools tend to be short, occurring in groups of parallel marks, and to have a more open cross section.”
It seems difficult to categorically reject human action on the rhinoceros jawbone of Billy, at least on the basis of the available published information. The action of carnivores can be safely ruled out. The geological explanation proposed by de Mortillet appears unlikely. The cut marks are on a bone that typically would be cut in butchering operations, and they appear to be in an appropriate location on the bone. In addition, the short length and parallel grouping of the marks resembles the pattern to be expected from the use of stone tools. So despite de Mortillet’s objections, it does not seem impossible that a stone instrument pressed forcefully on a bone could make the kind of marks found on the Miocene rhinoceros fossil from Billy, France.
2.7 Colline de Sansan, France ( Middle Miocene)
The report of the rhinoceros jaw of Billy led to the opening, at the meeting of the French Academy of Sciences on April 20, 1868, of a sealed packet deposited at the Academy on May 16, 1864 by the researchers F. Garrigou and H. Filhol. These gentlemen wrote on that date: “We now have sufficient evidence to permit us to suppose that the contemporaneity of human beings and Miocene mammals is demonstrated” (Garrigou and Filhol 1868, p. 819). This evidence was a collection of bones, apparently intentionally broken, from Sansan (Gers), France. Especially noteworthy were broken bones of the small deer Dicrocerus elegans. The bone beds of Sansan were judged to be of Middle Miocene age (Mayencian). One may consider the devastating effect that the presence of human beings about
15 million years ago would have on current evolutionary doctrines.
Were the nineteenth-century scientists correct in their determination of the age of the site? Once more, the answer to this question is yes. Modern authorities (Romer 1966, p. 334) still place Sansan in the Middle Miocene, and Dicrocerus elegans is assigned to the Helvetian land mammal stage, which is considered Middle Miocene (Klein 1973, p. 566; Romer 1966, p. 334).
According to de Mortillet, Edouard Lartet, who also excavated fossils from Sansan and himself sent to Garrigou some of the bones on which Garrigou and Filhol founded their assertions, did not believe in human action on the bones. There were many broken bones at Sansan, and de Mortillet (1883, pp. 64 –65), in his usual fashion, said that some were broken at the time of fossilization, perhaps by dessication, and others afterward by movement of the strata.
Garrigou, however, maintained his conviction that the bones of Sansan had been broken by humans, in the course of extracting marrow. He made his case in 1871 at the meeting in Bologna, Italy, of the International Congress of Prehistoric Anthropology and Archeology. Garrigou (1873) first presented to the Congress a series of recent bones with undisputed marks of butchering and breaking. For comparison, he then presented bones of the small deer (Dicrocerus elegans) collected from Sansan. Among them was a humerus (the long bone of the upper forelimb) with a set of breaks exactly resembling those on a cow humerus from the Neolithic age. On its inner surface, the deer bone bore a profound incision, filled up with material from the stratum in which it was found.
Garrigou also displayed a radius (one of the bones of the lower forelimb) presenting a longitudinal fracture terminating at a right angle to the end of the bone. The fracture had the same patina as the rest of the bone, indicating the break was made when the bone was fresh, and the broken part had a surface so clean and sharp that it was impossible to see it as a natural geological effect. Subterranean pressure and shifting, if it had occurred, would have almost certainly damaged the perfectly intact edges and joint surfaces of the fractured long bone. In making these observations, Garrigou showed a good grasp of taphonomic principles. He also pointed out that the longitudinal fracture on the specimen he showed was identical to those encountered on hundreds of similar bones at Sansan.
Here we may note that longitudinal fracturing is characteristic of breaking bone for the purpose of obtaining marrow. Binford (1981, p. 162) stated: “Marrow is primarily contained in the medullary cavity of the body or shaft of long bones. This shaft is shaped like a cylinder, so access to the medullary cavity and hence the marrow is facilitated by collapsing or fracturing the cylinder longitudinally. Transversal fractures in the center of long-bone shafts do not provide ready access to the marrow.”
Garrigou also showed that many of the bone fragments had very fine and delicate striations such as found on broken bones of the Late Pleistocene. The marks could be indications of processing the bone for marrow breaking, as described by Binford: “The secret of controlled breakage of marrow bones is the removal of the periosteum [the sheath of connective tissue covering bone surfaces] in the area to be impacted. The Nunamiut invariably do this by scraping it back with the edge of a knife, a rough surface on a hammerstone, or almost any handy crude scraping tool. This means that longitudinal scratches and striations along the shafts of long bones are commonly produced when bones are prepared for cracking during marrow processing. Such marks are noted in Mousterian [Neanderthal] assemblages” (Binford 1981, p. 134).
Garrigou also displayed two metacarpals (foot bones), each with the smaller end removed by a direct blow. He pointed out that since flint tools had been found in the Miocene, one should not be astonished to find the effects of their usage. Food is the primary human need, so one should expect to observe signs of human attempts to secure it (Garrigou 1873, p. 137). In the next three chapters, we shall consider in detail the evidence for flint tools in the Miocene and Pliocene, but for now we should keep in mind that reports of such discoveries were very common at this time, and were accepted by many reputable scientists.
Garrigou did, however, meet with strong opposition at the Congress, from, among others, Professor Japetus Steenstrup, secretary of the Danish Royal Society of Science and director of the Museum of Zoology in Copenhagen. Steenstrup argued that a broken bone should have a percussion mark (Garrigou 1873, p. 140). The fractured edges of a bone fragment should converge at this point, where a blow had been struck. According to Steenstrup, the bones displayed by Garrigou did not show percussion marks and converging fractures. Steenstrup therefore believed that the bones had been broken by the gnawing of carnivores.
Garrigou disagreed that fragments must show a percussion mark; its absence would not, in the case of any particular fragment, rule out direct impact as the cause of fracturing. In experiments, Garrigou had seen fresh bones broken into many flakes by a blow, and only one or two flakes would have the percussion marks. And if the instrument used happened to be sharply pointed, the bone would split immediately like a piece of wood, with no percussion imprint whatsoever (Garrigou 1873, p. 141).
The observations of both Steenstrup and Garrigou are in line with modern test data. In support of Steenstrup, we find that Binford stated (1981, p. 163): “Impact scars from hitting the bone during marrow cracking are quite distinctive. First, they are almost always at a single impact point, which results in driving off short but rapidly expanding flakes inside the bone cylinder. At the point of impact the bone may be notched, in that a crescent-shaped notch is produced in the fracture edge of the bone.” But Binford’s surveys showed that only about
14–17 percent of bone splinters in marrow cracking assemblages will have impact notches on them, indicating human action; this lines up with Garrigou’s assertion that the vast majority of fragments will not have the impact marks. It would seem appropriate to analyze some Sansan bone splinter assemblages in terms of Binford’s impact notch frequency criterion to test for human or animal action.
Garrigou also pointed out that Steenstrup’s assertion that the bone breakage was caused by animal gnawing was incorrect, because the bones should then have displayed the marks of their canines and molars, and such was not the case. Animal gnawing results in extensive bone destruction, and the clean edges of the longitudinal fractures described by Garrigou contradicted that hypothesis.
Binford (1981, pp. 179–180) advised: “If one observes a pattern of bone destruction and knows that destruction is the normal consequence of animal behavior, one should view one’s task as disproof of the proposition that animals were responsible for the observed patterns. . . . One might suspect that the reverse strategy might prove helpful when a pattern of bone breakage or modification by percussion is noted. Namely, knowing that breakage is a normal consequence of human behavior, one should view one’s task the disproof of the proposal that man was responsible.” The bones of Sansan seem to fit in the category of breakage rather than destruction.
What sort of tests might be applied to disprove human action? Binford pointed out that animals typically destroy the articulator (or joint) ends of long bones during gnawing, whereas human breakage normally does not result in articulator destruction. Binford (1981, p. 173) suggested that it should therefore be possible to examine ratios of articulator ends to shaft pieces in broken bone assemblages as a method of discriminating between animal and human action. In the case of animal action, one would expect a low ratio of articulator ends to be present. Of course, the possibility that animals might scavenge bones left by humans introduces a complicating factor.
So in the case of the broken bones of Sansan we once more encounter evidence for a human presence in very ancient times. This evidence certainly cannot be ruled out in the absence of further study. Garrigou’s methodology and analysis appear to be quite rigorous, relying on sound taphonomic principles, extensive comparison with bones indisputably broken by human action, and evidence gathered from direct experiments in bone breakage patterns. We can only wonder why this report has remained buried. Whatever the reason, it would appear that the present data collection upon which ideas about human origins are based may be quite incomplete.