In 1912, a British amateur archeologist named Charles Dawson wrote to London's Natural History Museum claiming to have discovered the missing evolutionary link between apes and humans in a fossil he had dug up in Piltdown, Sussex. This was the beginning of the Piltdown Man hoax, one of the most successful and consequential hoaxes in scientific history. Dawson's Piltdown Man was conclusively established as a hoax in 1953, after decades of leading scientists down the wrong path of evolutionary study.
The Piltdown Man was a collection of "fossils" assumed to be from the same Pleistocene- or Pliocene-era early human, according to Isabelle De Groote, a professor at the Research Centre in Evolutionary Anthropology and Palaeoecology at Liverpool John Moores University and author of the 2016 article "New genetic and morphological evidence suggests a single hoaxes created ‘Piltdown Man.'"
The Piltdown Man fossils were found over several years and included a mandible and set of teeth, parts of a human-like skull and a canine tooth. There were also rudimentary stone tools, a carved slab of bone and fragments of fossils from Pleistocene- or Pliocene-era mammals, De Groote told Live Science.
The fossils had the same dark reddish-brown color as the surrounding Pleistocene or Pliocene gravel pits in which they were uncovered. The mandible resembled an ape's, while the skull appeared human, and the canine tooth could have belonged to either species. Taken together, the fossils seemed to suggest that their owner exhibited characteristics of both apes and humans and was, therefore, the missing link.
In reality, the jawbones and tooth came from an orangutan and the skulls from medieval human bones, De Groote said.
For more than a century, the identity of the creator of the fake fossils was unknown, but De Groote's study, published in August 2016 by Royal Society Open Science, determined that Dawson was the most likely sole forger.
According to Peter Hancock, author of "Hoax Springs Eternal: The Psychology of Cognitive Deception," the Piltdown Man hoax really begins with the 1859 publication of Charles Darwin's "On the Origin of Species." If Darwin's theory of evolution by natural selection was true, people thought, there should be fossils that clearly connected apes to modern humans. This connecting fossil came to be called the missing link. The search for it became a race that overtook the 19th century archaeological community.
Scientists in Belgium, France and Germany uncovered early human fossils that shined light on human evolution. Among these findings was the highly significant jaw fossil from Homo heidelbergensis, found in Germany in 1907. Geopolitical ties between the United Kingdom and the continent were relatively weak; the tensions that would come to light in World War I were already brewing. The British were jealous of these findings and wanted to find their own "early man" to bring glory to England. Hancock wrote that the French teased the British about their lack of fossils, calling them "pebble hunters."
Into this environment came Charles Dawson, a solicitor and amateur archaeologist who had previously donated a collection of fossils to the British Museum. According to Keith Stuart Thomson's article in the journal American Scientist, “Piltdown Man: The Great English Mystery Story,” Dawson had a history of deception: he had plagiarized a historical account of Hastings Castle and had come into his estate through pretending to be an official part of the Sussex Archaeological Society. Unfortunately, these facts were unknown; if people had been aware of them, perhaps they would not have taken his Piltdown fossils seriously.
English scientists had determined that they were most likely to uncover a British early man in the Pleistocene gravel pits in Southern England. One day, Dawson saw that some gravel had been excavated to build a pond in Piltdown, Sussex. He became fascinated with the spot and set up investigations.
'Uncovering' fake fossils
The exact chronology of the early Piltdown findings is unclear. According to Thomson, Dawson said that in 1908 some gravel pit workers came to him with something "like a coconut" that was presumably a skull. He asked a local chemistry teacher named Samuel Allinson Woodhead to join him in an excavation, but the two found only some pieces of ironstone that resembled the "skull." In 1909, Dawson partnered with a Jesuit named Pierre Teilhard de Chardin, who would become one of the suspects in the creation of the forged fossils. The two excavated together over the next few years and were occasionally joined by other amateur archaeologists. They found various remains thought to be from early humans. At some point between 1909 and 1911, Dawson asked Woodhead about treating bones to make them look like fossils, according to Thomson.
Historians know that in February 1912, Dawson reached out to Arthur Smith Woodward, keeper of geology at the Natural History Museum and a friend of Dawson's. According to De Groote, Dawson wrote that he had found a "thick portion of a human skull which will rival H. heidelbergensis in solidity." He showed Smith Woodward pieces of supposed skull.
According to Michael Farquhar, author of "A Treasury of Deception: Liars, Misleaders, Hoodwinkers, and the Extraordinary True Story of History’s Greatest Hoaxes, Fakes, and Frauds," Smith Woodward was so excited by the findings that he dedicated the rest of his life to studying them. He traveled with Dawson to the Piltdown site and began excavating with him. They found a mandible, a set of teeth, more skull fragments and primitive tools. They suggested that these remnants had all belonged to the same individual. These fake fossils became known as Piltdown Man I.
Smith Woodward constructed the fragments into a skull that he hypothesized was the missing link, a human ancestor that lived 500,000 years ago.
Piltdown Man success
According to the Natural History Museum, London, Smith Woodward and Dawson announced their findings at a Geological Society in December of 1912. They called their discovery Eoanthropus dawsoni (Dawson's dawn man). While there were a few skeptics, mostly outside of the United Kingdom, most of the public and scientific community accepted their story as true and exciting.
Dawson and Smith Woodward continued their excavations until 1914. They uncovered the canine tooth and carved bone slab, which became known as the "cricket bat" because of its shape, said De Groote. The idea that this early Englishman had actually played a rudimentary form of cricket became popular.
Their work together was disrupted by World War I and Dawson's declining health. Nevertheless, in 1915, Dawson wrote to Smith Woodward that he had uncovered more remains about two miles from the others. These remains became known as Piltdown II, and, according to Farquhar, they quieted the few remaining skeptics. The president of the American Museum of Natural History wrote that "If there's Providence hanging over the affairs of prehistoric man it certainly manifested itself in this case." Textbooks began to include Eoanthropus dawsoni.
In "The Last Lost World: Ice Ages, Human Origins, and the Invention of the Pleistocene," authors Lydia Pyne and Stephen J. Pyne describe the reasoning behind the public and scientific community's belief that the Piltdown Man was real. In addition to containing bones that resembled both ape and human, the skull was bigger than previous early human skull discoveries. This seemed to suggest that the Piltdown Man was a more highly evolved early human. That the largest early human skull was found in England appealed to British nationalism. Its discovery followed a similar narrative to that of genuine artifacts. "In brief, it fit so many gaps in knowledge, ambition, and desire that it might have been explicitly contrived to do so," the authors wrote. "And it was."
In 1916, Dawson died. This left Smith Woodward as the main advocate for the Piltdown Man, and he filled the role enthusiastically. He began referring to the Piltdown Man as "The Earliest Englishman" and published a short book with the title. According to the Pynes, other high-profile British scientists expressed fascination with the Piltdown Man, as did Sir Arthur Conan Doyle, author of the Sherlock Holmes books. In the 1925 Scopes Monkey Trial, Clarence Darrow introduced the Piltdown Man as evidence for human evolution in his defense of John Scopes.
More early human fossils — real ones — were discovered throughout the 1920s and '30s. As they came to light, scientists noticed that they had little in common with the Piltdown Man. When chemical tests that would help re-examine the Piltdown Man were developed in the late 1940s, scientists took advantage of them, according to Kristi Lew, author of "Evolution: The Adaptation and Survival of Species."
Joseph Weiner, Kenneth Oakley and Wilfred Le Gros Park were three such inquiring scientists from Oxford and the British Museum. They subjected the Piltdown Man fossils to a series of rigorous chemical tests, which ultimately showed that they were fakes. A fluoride-based test dated the upper part of the skull at about 500 years old and the jawbone at a few decades old. A nitrogen analysis confirmed the results. Additionally, the tests showed that the fossils had been stained with iron and potassium dichromate to make them appear ancient. Scientists noticed that the teeth in the jaw had been filed down to make them appear human-like. The jaw was broken where it would attach to the cranium, thus allowing for smooth reattachment, according to Pyne and Pyne, and the partial upper skull suggested a large cranium without specifying measurements so gullible scientists could project their assumptions onto it.
Weiner, Oakley and Park published their findings in Time magazine in November 1953, and the world learned that the Piltdown Man was a fake. Further findings published in 1955 showed that the (real) mammalian fossils and rudimentary tools were planted at the site. The "cricket bat" was likely fossilized elephant bone recently carved with a steel knife, said De Groote. Later, they determined that the jaw and canine tooth came from an orangutan.
The Piltdown hoax was revealed, but significant damage had already been done. It led scientists down the wrong path in understanding human evolution for decades. Because scientists assumed that it was the missing link, some were skeptical of other genuine finds that did not match with the narrative the Piltdown Man suggested. This was especially true of discoveries made in Asia and Africa, such as the 1924 discovery of the Taung Child, because they took the focus away from Europe, according to Pyne and Pyne.
A hoaxer identified
One mystery still remained: who had made the fake fossils? Most experts believed that Dawson had a role in the forgery, but many thought he had help. Smith Woodward was a likely accomplice, according to Pyne and Pyne. Francis Thackery, a South African paleoanthropologist told Science magazine that he believed Teilhard de Chardin, who had worked with Dawson on early Piltdown excavations, aided Dawson. Other suspects have included Martin Hinton, a volunteer on the Piltdown dig who disliked Smith Woodward, and Sir Arthur Conan Doyle, who lived near the Piltdown site and belonged to the same amateur archaeology club as Dawson.
In August 2016, De Groote and her team published "New genetic and morphological evidence suggests a single hoaxes created ‘Piltdown Man,'" a study that indicated the fossils had been made by a single forger, likely Dawson, thereby solving the mystery for all but the most skeptic.
"Techniques such as microCT scanning, ancient DNA analyses, 3D microscopy etc., have only been available a number of years and we wanted to apply those to the study of Piltdown," she said. The team conducted these tests on the human and ape material from the Piltdown site.
"Extracting DNA from such 'messed-about-with' specimens is not an easy task," said De Groote, but eventually the team was able to determine that not only did the jaw and teeth specimens belong to apes, they came from the same orangutan. De Groote suspects the forger got them at a curiosity shop or from a museum collection; Dawson would have had access to both. The tests also revealed that the cranial bones came from two or three medieval humans, "evidently purposely selected for their cranial thickness," she said.
Among De Groote's findings was another forgery technique. "Several of the bones and teeth were loaded with gravel that was held in place with pebble plugs, all originating from sediment similar to that found at the Piltdown site," she said. The gravel and pebble plugs were held in place with distinctive putty, stained reddish brown like the rest of the bones. De Groote thinks gravel was added to make the bones heavier since fossils weigh more than new bones.
"The consistency in the modus operandi and the use of a limited number of specimens to create both the Piltdown I and Piltdown II material are indicative of a single forger," De Groote said. She believes that Dawson was man behind the hoax.
Dawson was the only person directly associated with the Piltdown II site, and her studies reveal that the forger, though possessing a relatively strong technique, was not a trained conservator. De Groote noted that his early letters reveal an obsession with joining the archaeological Royal Society, and he lamented not yet having made a big discovery. In 1913, he was finally nominated to join because of the Piltdown finds.
De Groote believes that solving the Piltdown hoax and identifying the forger is still important today. The hoax continues to be a relevant cautionary tale for scientists "not to see what they want to see, but to remain objective and to subject even their own findings to the strongest scientific scrutiny," she wrote in her study. "The field of palaeoanthropology is still guilty of fossil hoarding/guarding and exclusivity, but recently, there have been some welcome developments … Such progress should help us avoid the mistakes that the scientific community made when Eoanthropus dawsoni was first announced."
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Jessie Szalay is a contributing writer to FSR Magazine. Prior to writing for Live Science, she was an editor at Living Social. She holds an MFA in nonfiction writing from George Mason University and a bachelor's degree in sociology from Kenyon College.