In November 1953 Piltdown Man hit the headlines again. This time revealed as a hoax. The so-called 'missing link' between humans and apes now became a sensation as a sophisticated and infamous scientific fraud.
In the 40 years since the original 1912 announcement of Piltdown Man, increasing numbers of ancient human fossils had been discovered, most notably from Africa, China and Indonesia, but also from Asia and Europe.
None of these discoveries showed the large brain and ape-like jaw of Piltdown Man. Instead they suggested that the jaws and teeth became human-like before the evolution of a large brain.
As the discrepancies became too many to ignore and as new dating technology emerged, investigations on the Piltdown fossils began again.
At the Natural History Museum in the late 1940s, Kenneth Oakley ran a series of fluorine tests that made use of fluorine's tendency to accumulate in calcium-containing organic matter such as bones and teeth. Oakley discovered the fossils were probably less than 50,000 years old, not nearly old enough to be from a species with such ape-like features.
Following this, the biological anthropologist Joseph Weiner and human anatomist Wilfrid Le Gros Clark, both from Oxford University, worked with Oakley to test the Piltdown fossils even more stringently.
Their results proved that the skull and jaw fragments actually came from 2 different species, a human and an ape, probably an orangutan. Scratches on the surfaces of the teeth, visible under the microscope, revealed that the teeth had been filed down to make them look human. They also discovered that most of the finds from the Piltdown site had been artificially stained to match the local gravels.
The conclusion: Piltdown Man was an audacious fake and a sophisticated scientific fraud.