17 December 2012

Five Lessons from Piltdown Man

Today is the 100th anniversary of the day that Piltdown Man was announced to the world. It remains a mystery that has not yet been solved a century later.

There were actually two important announcements in the Piltdown affair: one in 1912 trumpeting the great fossil discovery, and one forty-one years later in 1953 when the wheels came off completely.

On December 18 1912, Charles Dawson, an amateur geologist, and Arthur Smith Woodward, Keeper of the Department of Geology at the British Museum, announced the discovery in England of the remains of a new form of primitive human. Nine pieces of a skull and part of a jaw had been unearthed in a gravel pit near Piltdown in Sussex. The skull fragments were decidedly human, though unusually thick; the piece of jaw was in many aspects ape-like but in others quite human. Woodward claimed that this unique combination justified creating a new genus and species and he named it, "in honour of its discoverer, Eoanthropus dawsoni," Dawson’s Dawn Man.

The Piltdown find was particularly exciting to British scientists. It fulfilled the prediction of many Darwinians that primitive man developed an advanced brain first, retaining an ape-like jaw that carried large fighting canines. The first discovery of ancient human remains in Britain, it also provided a major boost to the national ego: the birthplace of Shakespeare and Newton could hardly be without earlier evidence of human cultural advances.

Only the left side of the jaw had been found, with two molar teeth still in place. But was it an ape jaw or a human jaw? The fragment was ape-like in shape and size but the two molars showed significant flat wear, a pattern occurring in humans but never in apes. Key parts of the jaw that would have tagged it as human or simian had been broken off, leaving a great deal of room for interpretation.

Several commentators thought that the pieces came from two individuals: the skull from a human, the jaw from an ape. Others, including Woodward, believed it would be highly unlikely to find the remains of two individuals so close together.

Strong support for Woodward’s position was provided by later finds in the Piltdown area: in 1913 a canine tooth that matched his predictions in size and wear pattern; in 1914, a piece of carved bone; and finally, in 1915, fragments of a second Piltdown Man.

Piltdown Man was not, however, granted a comfortable home in science's world view of our past. For the next thirty years opinion was strongly divided. There were those who defended him as the definitive proto-Englishman. And there were those who maintained that, however unlikely, the skull was human while the jaw came from an ape. As more fossil humans were unearthed around the world and the jigsaw puzzle picture of our pre-history took a more definite shape, the odd collection of bone bits from the Sussex gravels became increasingly hard to fit into our collective understanding. Edwin Ray Lankester, at one time Director of the British Museum (Natural History), brushed the contradictions under the rug: he saw this ape-like, human-like creature as an evolutionary link between apes and men, and hence “the most startling and significant fossil bone that has ever been brought to light.” The American palaeontologist Henry Fairfield Osborn, a more skeptical observer, stated flat-out that the skull was very much a modern human one except for being very thick, and the jaw was identical to an ape’s. But he failed to make the obvious deduction that the two did not belong together. He could only conclude that Piltdown race was “a side-branch of the human family.”

In 1953, three British scientists began to ask some new questions about Britain's most famous fossil, applying newly-developed chemical aging tests. Their paper, published by the British Museum, was a bombshell, and not only to a few specialists. "Piltdown Man Forgery", The Times headline of November 21, was typical of the reaction from the world press.

The fossils, the analysis showed, had been artificially stained by a chemical bath to give the appearance of age; some had also been dipped in iron sulphate to impart the rusty colour of long oxidation in an iron-rich environment. The jaw's molars had been filed down to simulate human wear patterns and the separate canine had also been stained and filed. The jaw itself came from an orangutan. The skull, though human, was only a few hundred years old.

The discovery of the forgery touched off the hunt for the forger. Charles Dawson was the first and most popular suspect, yet the next 60 years have seen a steady trickle of papers and books offering new theories. Today the long list of the accused includes prominent scientists, amateur geologists and anthropologists and members of the British Museum staff, though Woodward himself has always been considered above suspicion. The debate is still active, largely because all of the evidence is either circumstantial or hearsay and none of the original principals is alive to tell his story.

I always through that it was weird that the best minds in the world took 40 years to twig to the possibility of fraud. There were a few veiled suggestions along the way that there was something not quite right about Piltdown man, but nobody came right out and shouted “J’accuse!” Forty years.

In my novel The Link, I explore what might have happened if someone had spotted the hoax back in 1912. In my fictional story, the one who identifies the fake is not a professional scientist. There’s a good reason for this. In a more innocent age, scientists were simply not used to their fellow seekers cooking the books. They were used to dealing with mysteries laid out by nature and, as Augustus Parker says in The Link, “Nature does not cheat.” Instead, someone outside of academic circles, someone with a fresh viewpoint, spots the fake.

Apart from the tendency of specialist researchers to miss the more devious possibilities presented by the Piltdown fragments, two World Wars seriously distracted the world of paleontology in the period between 1912 and 1953. Any number of workers in the field – senior as well as junior – were redirected from their studies into wartime activities, and practical branches of science such as cryptology and electronics tended to hog the scientific stage.

So maybe it’s not so surprising that the Piltdown perpetrator got away with it for so long. But why should we care today, in 2012? Surely the exposure was 60 years ago. Science has moved on, bruised but much the wiser.

Well, there are lessons to be taken from the Piltdown episode, lessons that apply not just to academic activities, but to everyday life as well.

1. While closely examining the trees, take a minute to check out the forest.
Scientists were focused on the actual fragments, rather than looking at the bigger picture: the process by which they were produced.

2. Assume the best of humanity and, at the same time, the worst.
The investigators forgot that there was a human factor involved in the Piltdown Man affair: specifically the man who discovered it.

3. When you have eliminated the impossible, whatever remains, however improbable, must be the truth.
It’s hard to beat the classics. This Sherlock Holmes truism should be taped to the wall of every scientist’s office. And everyone else’s for that matter.

4. The simple answer is usually the correct one.
This is a simple-English bastardization of Occam’s razor, the principle first stated by the 14th century logician and Franciscan friar William of Ockham. What he actually said was "Pluralitas non est ponenda sine neccesitate," which of course translates to "Entities should not be multiplied unnecessarily," but I prefer the modern restatement. Osborn’s failure to draw the obvious conclusion about Piltdown from the bare facts is a primary failing to observe the razor. 

5. If it seems too good to be true, it probably is.

Whether it's money from Nairobi or fossils that precisely fit your theory, little alarm bells should be ringing.

Science has generally taken these lessons to heart although, like any endeavour where humans are involved, there are occasional failings.

More close shaves from Occam's razor in future blogs. 

Doug Elliott’s historical thriller The Link is available as a Kindle book from Amazon here.

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