DNA analysis determined that both the canine tooth from the first Piltdown site and a molar tooth from the second site probably came from one orangutan related to the orangutans that now occupy Southwest Sarawak, Borneo. The shape and form of a molar tooth from the second Piltdown site was also found to have originated from the other side of a jawbone that had been planted in the first site.
"Our work shows that a century on, we can add a new chapter to the Piltdown story through new investigative techniques," senior author Chris Stringer, a human origins expert at the Natural History Museum, said. "For example, we found surprising evidence that the forger had even removed the molars in order to modify them, and had then replaced them in the jawbone."
3D x-ray imaging further showed that many of the bones and a tooth were filled with Piltdown gravel. The openings in the "remains" were plugged with small pebbles, while holes in the skull were filled with the same dental putty used to reset the teeth in the jaw, and to reconstruct one of the teeth that fell apart while it was being ground down.
Stringer and his colleagues believe that, because of the identified consistency in the manner that the fraud fossils were crafted, Dawson was the perpetrator.
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"A single forger was at hand here," De Groote said. "Dawson definitely had the connections to acquire the specimens, the skills and means to do this himself. Whether he had a technician carry out the work is unclear, but we believe he was the mastermind behind all the finds."
As for why Sir Doyle was ruled out, she explained, "It is highly doubtful that Sir Arthur Conan Doyle was involved. He lived nearby and Dawson may have been inspired by his books. Who knows? But Sir Arthur Conan Doyle would not have had the knowledge to carry this out."
Intriguingly, Dawson's highly successful younger brother, Arthur Trevor, received a knighthood and public acclaim in November 1909, not too long before the great public unveiling of Piltdown Man. Dawson's wife Hélène wrote a letter on December 28 of that year to the Home Secretary Herbert Gladstone, asking that her husband's scientific work be acknowledged because "he is entitled to some recognition."
It appears that Dawson might have started off as an ambitious scientist, did not achieve his career goals, became bitter and disillusioned, and then turned to a life of fraud, which proved to turn things around for the better for him.
At least 38 forgeries are now associated with Dawson.
"If he hadn't given in to this dark side of himself that wanted fame and fooled scientists, he could have been a well-established scientist," De Groote said.
Stephen Donovan, a professor at the Naturalis Biodiversity Center who has also extensively studied Piltdown Man said, "People have been saying for years that Dawson couldn't have done it, he was an amateur, he didn't have the resources or know-how, most of which isn't true and none of which is relevant. He was a serial scientific forger, talented at what he did and Piltdown Man was his greatest forgery, fooling the entire British paleoanthropological community. We should, in truth, marvel at his unique suite of abilities that enabled him to be so successful."
Donovan added that the new research offers "a fine example of applying new techniques to old specimens. If we didn't preserve specimens in museums, such studies would not be possible."
Dawson died 100 years ago this month. Piltdown Man is still kept at the Natural History Museum.
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