Thursday, August 19, 2010

Unmasking Eoanthropus dawsoni, The First Englishman

This post was chosen as an Editor's Selection for ResearchBlogging.orgFellow blogger and Scientope Scicurious played host to the most recent edition of The Giant’s Shoulders, a blog carnival that recognizes folks who use classic science papers in their writing. Sci put together a spectacular collection of posts based on the theme of Fools, Frauds, and Failures, and it’s certainly worth perusing.

I had high hopes for participating in this round of the carnival, but the truth be told, life just got the better of me. I really don’t have an excuse since GS is published monthly, and I had ample time to get started, but every time I sat down to write this post, *something* would happen—the cat would begin to beat up the kitten, the laundry would need to be folded, S would suggest we watch a movie, Bear Grylls would make another close escape, the Mets would lose (again) sending me into a spiral of despair, you get the idea. I really wanted to participate though because I have the perfect anthropological case to fit all three elements of the theme. So I’m a few days late, but I’m inviting you to take a hop across the Pond with me to explore a case of anthropological foolery, fraud, and failure that will probably be familiar to many anthro students.

The Stage is Set

Archaeology can hold the key to national identity. Think about it: a find, even if it’s not King Tut’s funerary mask, can provide a testament to the accomplishments of a civilization. It anchors the heritage of a people. So it should come as no surprise that when archaeologists began to piece together the story of human evolution that everyone wanted to claim a place in the narrative—as evolution came to be more accepted in the late 19th-century, there was a certain pride in claiming a human ancestor within the boundaries of the nation. It provided a sense of origin for people and heightened their sense of nativism.

The Germans had Neanderthals (discovered in 1856), the French proudly laid claim to Cro Magnon (1868), and fossils had also been found in Belgium (1886, Neanderthal), Spain (1848, Neanderthal), and even Holland (1890s, Pithecanthropus erectus—Java man) had a claim to human evolutionary history with a find on an outpost of the colony. England, however, could make no such claim. In fact, the absence of fossilized evidence of human evolution within England could only mean that the English were not native to their soil (1). It was a thought that did not sit well with many Englishmen. Other nations took the opportunity to criticize the English archaeological record—calling the paleontology efforts of the English “pebble collecting” (2).

The Find

The English didn’t have to endure ridicule for long, however. The year was 1912 and amateur archaeologist and geologist Charles Dawson and Sir Arthur Smith Woodward, the keeper of the British Museum's Natural History Department, unearthed several skull fragments in a quarry in the Piltdown section of Sussex, England. At last! England could claim a human ancestor within her boundaries! Dubbed Eoanthropus dawsoni, meaning Dawson’s Dawn Man and known locally as Piltdown man, the bone fragments showed signs of being the most important archaeological find of all time: it was potentially the missing link! The first Englishman had restored the nation to it’s rightful place on the political totem pole.

Although evolution was becoming more accepted, people still weren’t quite so comfortable with the picture of evolution itself. Java man, for example, was very apelike in appearance: the skull featured a sloping forehead, large eyebrow ridges and a relatively small brain case (900 cubic centimeters versus 1450 cubic centimeters for modern humans) (2). The skull was at once apelike and human-like. And other bones closely matched those found in modern humans:
All this evidence suggested that ancient human ancestors had primitive heads and, by implication, primitive brains, seated atop rather modern-looking bodies. This further implied that the human body evolved first followed only later by the development of the brain and associated human intelligence (3).
This ran counter to the expectations of the time. People wanted to believe that intelligence led evolution—so the brain would have developed first, which is a simple way of explaining the brain-centered paradigm that gripped scientists—and society—at the time. Researchers were looking for a creature with the body of an ape, and the brain of a human being (4).

At first glance the Piltdown find supported the expectations set by the brain-centered paradigm. When pieced together, the fragments appeared to mimic the dome of the modern skull. The facial pieces were missing, but part of a jaw was subsequently discovered nearby. It was like nothing ever seen before—it looked very much like the jaw of an ape, but the molars were worn as if by human mastication. George Grant MacCurdy writes in American Anthropologist:
When the pieces of the cranium were put together it was possible to estimate the cranial capacity, which Dr. A Smith Woodward gives as not less than 1070 cc. The bones are touch and hard, and the walls of the brain-case exceedingly thick, the average thickness of the frontal and parietal being at least one centimeter. The face and the greater part of the forehead are missing … The forehead is steeper and the brow ridge feebler than in the later Neandertal type. The cranium is low and broad, with a marked flatness on top, and the mastoid processes are relatively small (1913: 249).
A thick brain case suggested a primitive nature, but the described features aligned it more closely with modern humans and perceived intelligence. The jaw, though not complete, curiously contained enough information to suggest its origins and purpose. It was missing the canines, which might have firmly identified it as belonging to an ape, and the molars showed evidence of being ground down from a sideways motion that apes cannot produce. So it seemed, not only did England have a stake in the evolutionary history of humankind, but with a single find they had managed to stake a claim to the oldest trace of human evolution. They proclaimed Neanderthal was an anomaly in the fossil record—it was younger than Piltdown, but had more primitive cranial features, therefore it must represent some moment of reversal in evolutionary history (5).

The Plot Thickens

To complicate the issue, flints were also found in the quarry—so now he was the oldest known tool user as well. While not every scientist was completely convinced, many saw what they wanted to see in the Piltdown skull:
Scientists have often remarked on the paucity of human remains that could with certainty be referred to in a very early epoch; a condition which more than anything else has kept in check the science of prehistoric archaeology. After all, there is no evidence quite so incontrovertible as the presence of a man’s own skeletal remains. We may justly differ on the question as to whether or not a given flint is an artifact; not so in the case of a human skull … Personally, I have for years been a believe in the prehistoric possibilities of southern England because of the outcrops of flint-bearing Chalk stretching from Dorset to Sussex on the south to Caddington and the Cromer Forest Beds on the north. Of all raw materials flint is perhaps the best suited to tempt nascent Homo to become a tool user (MacCurdy 1913: 252).
Dawson and Woodward continued to work the site, and were able to unearth some additional animal remain (proof that those flints were being used!) as well as some teeth. MacCurdy follows up on this with another article where he says:
The nasal bones are said to “resemble those of existing Melanesian and African races, rather than those of the Eurasian type.” In thickness they correspond to the bones of the skull previously found. The canine tooth not only corresponds in size to the mandible but belongs to the same half as that recovered. It likewise agrees with the two molar teeth in the degree of wear due to mastication. The extreme apex is missing, but whether by wear or by accidental fracture is not determinable. The enamel on the inner face of the crown, has been completely removed by wear against a single opposing tooth … On the other hand there is no facet due to wear against the outer upper incisor, such as often occurs in the apes (1914: 333).
In 1915 another set of skull fragments were found on a farm about two miles from Piltdown. This subsequent find was very similar to the first, and did much to reduce the concerns of many—though not all—researchers. After all, two similar finds suggested that there was a pattern.

The Truth Revealed

Dawson died the following year and no additional evidence of the human evolutionary tree was recovered from Piltdown, but the fossil record continued to grow, and as it did it cast doubt on the validity of the brain-centered paradigm—and the Piltdown remains. Australopithecus africanus emerged in the 1920s, followed by other variations of Australopithecus in the 30s and 40s. Additional Neanderthal fossils were recovered—some even in England! Piltdown man became more and more marginalized, ignored, and incidental.

Woodward died in 1944. In 1949 the Piltdown remains were dated using a new procedure that measured the amount of fluorine in the bones. It is reported that Woodward had known of similar techniques for dating, but refused to allow these techniques to be applies to the remains (6). The fluorine tests placed the bones at no more than 50,000 years old. How then could they then be the missing link? In 1953 more precise tests were conducted, and it was determined that the levels of fluorine varied greatly between the skull fragments and the jaw piece—there could be no denying the evidence: they were from two different creatures! The skull was from a modern human and the jaw belonged to an orangutan. The jaw had been intentionally modified to fit what people wanted to see, and imagination and expectation did the rest.

Egg on Our Faces

Piltdown left a stain on anthropology. It created unnecessary doubt for the sake of alleviating wounded nationalistic pride. It was a successful hoax as it persisted for 30-odd years. But it was in part successful because it showed the scientific community a truth that they were comfortable with—a truth for which they were willing to ignore the weight of other evidence. Science, above all, must be objective. While many have used Piltdown as evidence that the fossil record is false and poorly misunderstood, I’d propose that Piltdown demonstrates that science can prevail even when popular beliefs run counter to the results.

There are many questions that remain since both Dawson and Woodward died before Piltdown man was officially debunked. And there were many other players in this game who may have contributed to the hoax. What I’ve presented here is a cursory look at one of the biggest anthropological frauds in history. If you’re interested in reading more, the following sources may be of interest:

Feder, Kenneth.
2002     Frauds, Myths, and Mysteries: Science and Pseudoscience in Archaeology. Fourth edition. McGraw Hill.


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Numbered citations:
(1) Feder, Kenneth. 2002 Frauds, Myths, and Mysteries: Science and Pseudoscience in Archaeology. Fourth edition. McGraw Hill: 62
(2) Feder 2002: 62
(3) Feder 2002: 62-63
(4) Feder 2002: 64
(5) Feder 2002: 68
(6) Feder 2002: 72

References cited:
ResearchBlogging.orgMacCurdy, G. (1913). Ancestor Hunting: The Significance of the Piltdown Skull American Anthropologist, 15 (2), 248-256 DOI: 10.1525/aa.1913.15.2.02a00050

MacCurdy, G. (1914). The Man of Piltdown American Anthropologist, 16 (2), 331-336 DOI: 10.1525/aa.1914.16.2.02a00110

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