The Piltdown Hoax
The Origin and Evolution of Man 1971
(reprinted from Introduction to Physical Anthropology, 1960)
 One of the most curious incidents in the history of science is the story of the Piltdown hoax, or fraud. It is, of course, easy to be wise after the event, and after the technical advances in science as well as the general improvement in our knowledge of the morphological evolution of the Hominoidea would make it virtually impossible for any hoaxer to foist such a chimera as Piltdown man upon the scientific world today.
Harsh words have been uttered about "second-raters" and this "sorry tale of incompetence," on the part of those who should have known better. But then, that is the definition of an expert: "one who should have known better." Those who occupy positions of authority are not always authorities on the subjects of their "authoritative" judgments. For an account of these "authoritative" judgments the reader should consult Gerrit S. Miller's paper, "The Controversy over 'Missing Links," Smithsonian Report for 1928 (Washington, D.C.: Smithsonian Institute, 1929), pp. 413-465.
In the history of science the Piltdown hoax is now of interest mainly insofar as it illustrates the power of a false expectation to create a state of mind on the part of the experts which would prepare them for accepting the frauds of a hoaxer. The belief in "missing links," indeed, in "the missing link", made it perfectly possible for the leading anthropologists of the day to accept a human cranium together with an ape-like jaw as belonging to one and the same individual. After all, what would the missing link connecting man with his ancestors be expected to look like, if not partly human and partly ape? And so the hoaxer worked with great skill to produce what everyone expected to see. It is a cautionary tale of the willingness to believe catered to by those willing to deceive. As the hoaxer might have said:
With jawbone of an ass great Samson slew
A lion; but my deed his feat surpasses
For forty years, and with a jawbone, too,
I made our scientific lions asses! *
The Piltdown remains are discussed here for several reasons. Firstly, because they have played a leading role for over forty years in discussions concerning the evolution of man, and secondly because they provide something of an illustration of the difficulties besetting the student of the fragmentary remains of hominoidswhether early or late. Finally, the whole story provides something of a cautionary lesson for those engaged in the evaluation of such remains.
"Discovered" between the years 1909-1915, by Mr. Charles Dawson, an amateur English archeologist, at Piltdown, near Lewes, in Sussex, England, Piltdown man's discovery was announced to the world in December 1912, and named the Dawn Man of Dawson, Eoanthropus dawsoni. A subsequent series of finds brought the alleged number of the type up to two. The remains consisted of the right half of a lower jaw with two molar teeth in situ, the left temporal, parietal, and nasal bones, a turbinate bone, and a good part of the frontal and occipital bones. The second find, stated to have been made at a distance of two miles from the first,  consisted of a molar tooth and parts of the frontal and occipital bones. Part of a third skull, found at Barcombe Mills near Piltdown remained undescribed until 1951. 2
Figure 1: Reconstruction of the spurious Piltdown skull. Only the right side of the mandible, the first two molars in situ in the orang jaw, and the probable chimpanzee canine are shown in this manufactured specimen. These structures are here drawn as of the left side to match the cranial bones.
The Barcombe Mills skull is in every respect modern, but from the character of its artificial staining it is probable that it was used for experimental purposes in preparing the forger's chef doeuvre. The Barcombe Mills skull consists of a large part of the frontal bone, a fragment of what may have been part of a right parietal, a pair of zygomatic bones which do not in any way fit the frontal, and a mandibular right second molar tooth. A canine tooth, allegedly found in 1915 in the same Pleistocene gravels from which the original bones were said to have been removed, is very chimpanzee-like in form.
The Piltdown remains immediately became bones of contention. 3 It was questioned whether the jaw and teeth could possibly belong with the hominid cranial bones. The former were apelike, the latter were unquestionably human. It was asking a great deal of anyone critically considering the evidence to believe that a chimpanzee-like mandible and canine tooth could possibly have belonged to a skull so like that of modem man. Morphologically, the association seemed to be so improbable that most students refused to accept the jaw and canine tooth as belonging to anything but an ape. On the other hand, Broom, who reexamined the Piltdown remains in 1949, 3 had very little doubt that the Piltdown mandible belonged to the same individual as the brain-case. He considered that Piltdown was a big-brained type of man that evolved on a quite different line from true Homo. As for the simian shelf (a sort of internal chin) in the Piltdown mandible, that, be reasoned, is probably not an indication of close affinity with the anthropoids, but a specialization due to evolution parallel with that of modem apes, just as the large brain of this type may have been a parallel development to what is found in the line of Homo.
There is not the slightest evidence that anthropoid apes ever existed in England. But even if they had it is extremely improbable that an anthropoid ape's mandible would be deposited in the same gravels with a human brain-case. It was pointed out, in opposition to this argument, that when the thigh-bone of Pithecanthropus erectus was described many students refused to accept it  as belonging with the skull cap because they felt it was too human-like for so primitive a skull. Today no one hesitates to accept the two bones as having belonged to the same type, if not the same individual. Evolution, insofar as it affects the various parts of the body, has been asymmetrical. The lower extremities attained their manlike form before the skull. Similarly, the skull in its various parts exhibits evidences of asymmetric evolution. In all early forms of man, the mandible seems to lag behind the brain-case in its development. The lack of a developed chin in most early forms of man is a good example. In the case of the Piltdown mandible, it was argued, we may be dealing with an example of asymmetric evolution in much the terms suggested by Broom. The simian shelf is not a primitive character in the Anthropomorpha. It is not present in any of the early anthropoid types, but is obviously a late specialization. If it developed in the great apes, why not in an aberrant branch of man as well? Despite these arguments, many students remained unconvinced. The mystery to many scientists will always remain how anyone with the slightest knowledge of osteology, the comparative osteology of the primates, could have failed to recognize that the mandible under no circumstances could be morphologically harmonized with the cranial bones. That it in fact belonged to an anthropoid ape. The great thickness of the cranial bones compared with the slimness of the mandible presents a striking disharmony such as is never seen in any normal skull. The canine tooth perfectly matched the anthropoid character of the jaw, and no known form of man was known to possess such a tooth. The openmindedness of the experts, however, was such that they were willing to grant the possibility that both mandible and canine belonged with the cranial bones.
If there was any doubt about the hominid character of the mandible and canine there was whatever concerning the brain-case, for in its reconstructed form this revealed an obvious member of the genus Homo of an early neanthropic type with skull bones almost twice as thick as those of modern man. The cranial capacity was computed to be between 1,200 and 1,400 cc., McGregor estimating it to be about 1,240 cc.
In association with the Piltdown fragments there was alleged to have been found a number of what appeared to be the simplest type of stone tools, "eoliths," a worked flint, and a large bone implement made from the thigh-bone of an extinct elephant, thought to be Elephas meridionalis. Since the latter lived in Europe in the Upper Pliocene and Lower Pleistocene the antiquity of the Piltdown remains was at first referred to the Lower Pleistocene, but it was subsequently shown that animal fossils of later date are found in the same gravels as were the Piltdown remains. A test of the fluorine content of the Piltdown bones showed their fluorine content to be incompatible with an extreme antiquity. The basis of the test is that a form of calcium phosphate, known as hydroxyapatite, is progressively converted to fluorapatite, as fluorine is absorbed from water in the soil. Under the same conditions, and particularly for neighboring fossils, the oldest bones are therefore those with the highest fluorine content. In September 1949, at a meeting of the British Association for the Advancement of Science, Dr. Kenneth Oakley announced the results of the application of the fluorine test on all the available Piltdown materials. 4
Oakley and Hoskins found that all the animal remains of undoubted Lower Pleistocene age from the Piltdown melange showed high fluorine content, while all those known to be of later Pleistocene age in the same bed showed a considerably lower fluorine content. All the remains of Piltdown man-and some 20 microsamples were anayzedshowed extremely little fluorine. It was concluded that fluorine had been deficient in the Piltdown groundwater since the gravel was accumulated. Nevertheless the test showed conclusively that none of the bones and teeth attributed to Piltdown man belonged to the Lower Pleistocene. However, the first test failed to be sufficiently discriminating, obtaining a similar fluorine content for both mandible and cranial bones. The mandible and associated brain-case being of the same age, it was argued, it was probable that they dated from the final settling of the gravel, which from the physiographic evidence, the paleontological findings, and the fluorine tests was now revised downwards as being not earlier than the last interglacial.
The Position, then, was that it was still open to scientists to argue about the naturalness of the association of an ape-like mandible with a typically human brain-case, but in the light of the revised dating it was suggested that the probabilities were in favor of mandible and cranial bones belonging together.
In 1951, Montagu examined the Piltdown remains and concluded that on morphological grounds the mandible could not possibly belong with the cranial bones. .5 In July 1953, Dr. J. S. Weiner of Oxford University decided that several things were not as they ought to be about the Piltdown remains. The flatness of the occlusal surfaces of the two molar teeth was quite unnatural and in un-apelike, the lack of smooth continuity of biting surface from one molar to the other, the unnaturally heavy wear of the immature canine, the whiteness of the dentine beneath the darkly stained surface of the tooth, all suggested that artificial filing and staining had been the methods by which the superficial appearances had been produced. Proceeding upon this assumption the mandible was subjected to a new fluorine test in which a drilling of deeper substance was analysed. This now yielded a figure of 0.03 per cent, as did the two molar teeth and the canine. The cranial fragments from site I yielded the much higher figure of 0.1 per cent, consistent with the value yielded by specimens of Late Ice Age. The artificial stain which had been used to give the bones an appearance of antiquity had falsified the first fluorine tests. But even before the second test the deeper drilling while in process produced an odor of "burning horn," like that associated with the drilling of fresh bone, an odor which was absent when the cranial bones were drilled. Furthermore, while the drilling of the mandible yielded shavings of bone as fresh bone does, the cranial bones yielded a fine powder as old bones do. It was now reasonably certain that the mandible was recent and did not belong with the older cranial bones.
Following these revealing findings a whole battery of tests were applied to the Piltdown fragments. Meanwhile, Weiner, Oakley, and Le Gros Clark, during the last week of November 1953, published "The Solution of the Piltdown Problem," in which they announced their findings and the conclusion that the Piltdown skull was a fake. 6 In January 1955, "Further Contributions to the Solution of the Piltdown Problem" was published, giving a detailed account of the results of the battery of tests to which the bones bad been submitted .7 This report, the work of a dozen investigators, showed that the mandible, stone artifacts, and the shaped Stegodon (Elephas planifrons) "tool" were all faked. The bone "tool" had been shaped with a steel knife from the long bone of a genuine fossil elephant, and the stone artifacts had been artificially stained and introduced into the Piltdown gravels. Four pieces of broken teeth probably representing two molars "associated" with the Piltdown remains have been identified as belonging o the fossil elephant Elephas planifrons. Since this  species of elephant does not occur in Western Europe the fragments of teeth must have been imported from some foreign source. A planifrons from Ichkeul in Tunisia, where the fossil remains of this species are abundant, yielded a radioactivity count practically identical with the planted Piltdown planifrons teeth. They were artificially stained to match the color of the other Piltdown plants. Sic transit Eoanthropus dawsoni.
Figure 2: "The Piltdown Committee." Personalities concerned with the Piltdown "discovery." Back Row: Mr. F. 0. Barlow, maker of the casts, Prof. G. Ellio Smith, anatomist, Mr. C. Dawson, the "discoverer," and Dr. A. S. Woodward, zoologist. Front Row. Dr A. S. Underwood, expert on teeth, Prof. Arthur Keith anatomist, W. P. Pycraft, zoologist and Woodward's assistant, and Sir Ray Lankester, zoologist. (From the painting by John Cooke, R. A., exhibited at the Royal Academy in 1915)
In 1959 de Vries and Oakley, by radiocarbon dating, showed that the Piltdown skull was 620 +/- 100 years old, and that the orang mandible was 500 +/- 100 years old. 8 Oakley points out that it is the custom among Dyaks in Borneo to keep orang skulls as fetishes for many generations, and it was doubtless from such a skull that the mandible was derived.
This is not the place to consider either the possible identity of the forger or his motives. For that story the reader may be referred to Dr. J, S. Weiner's fascinating anthropological "whodunit," The Piltdown Forgery (Oxford University Press), 1955, and to Ronald Millar's The Piltdown Men (London: Victor Gollancz, 1972).
Source: Ashley Montagu, Introduction to Physical Anthropology, 3rd ed. (Springfield, Ill.:
Charles C. Thomas, 1960), pp. 220-230. Reprinted by permission of the author.
* H. A C. Evans, The New Statesman and Nation, 19 December 1953, p. 805.
Smithsonian Report for 1926 (Washingtron, D. C., 1926), pp. 413-465.
Nature, 165 Z(1950), 379.
n. s., IV (1951), 3-7.
6 Bull. Brit. Mus, (Nat. Hist.) 11 (1953), 139-146.
7 Bull. Brit. Mus. (Nat. Hist.): 11 (1955), 227-287.
8 H. de Vries and Kenneth Oakley "Radiocarbon Dating of the Piltdown Skull and Jaw," Nature, 184 (1959), 224-226.