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Science Being Slowed Down by Fraud
In 1900 little was known about our prehistoric ancestors. The little we do know originates from not too many ancient bones. Most bones decay. Just one in every million fossilises and such a fossil still has to be discovered. The fossils scientist had to work with around 1900 were found in Europe and Asia. The big question was whether one of these fossils was the humanlike ancestor that evolved at first from the anthropoids and headed for the modern man.
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fig. 2.6.1:
A reconstruction drawing of the Piltdownman |
In 1909 a few amateur researchers thought they had found the answer to this question. In the English shire of Sussex near Piltdown, in a gravel pit, the shovel of a workman hit something that looked like a coconut. The solicitor and amateur geologist Charles Dawson studied the fragments and concluded that the pieces were from a human skull. Dawson investigated the location together with the curator of the geological department of the Natural History Museum in London, Arthur Smith Woodward. In total they discovered nine fragments of a brain case, mainly of the left side of the skull and the right side of the lower jaw with two teeth which resembled human teeth. Furthermore flint tools and fossil bones of extinct animals were found. They presented their discovery to the famous anatomist Arthur Keeth. He had already been investigating the origin of the ancient Briton for a long time. According to Keeth this skull had a brain volume as large as a modern human's skull. He thought that the discovery was the oldest hominid fossil. He called it: Eoanthropus dawsoni (Dawson's Dawnman). It was an instant hit. The discovery fully matched the line of thinking about human origin. English anthropologists welcomed it jubilantly. They believed that the brains, which played the leading part in mankind's survival, had already increased in size in an early stage of evolution, while teeth and attitude came later. Arthur Keeth and others received knighthood. In future great Britain was assured of being the birthplace of modern man.
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fig 2.6.2:
Raymond Dart with the Taung scull in his hands |
In 1924, however, the superiority of the Britons was threatened by a surprising discovery in Africa. In the Buxton limestone quarry north of Kimberley, where diamonds were extracted, there was snow-white limestone next to polluted pink coloured limestone. The pink material contained bones. An employee of the limestone pit, a certain De Bruin, had already collected skulls of baboons for years. One day he noticed a strange skull. He sent it to the Head of the medical faculty of Johannesburg, Professor Raymond Dart, an anatomist. On November 28 in 1924 Dart's best friend got married with Dart as his witness. While the professor was changing a chest with unknown contents was delivered. It contained pieces of limestone and a fossil skull. Dart had enjoyed an excellent training in brain anatomy in England and, consequently, saw at once that the skull could not be of a monkey. 'A shiver of excitement went through me. It was not an ordinary monkeylike skull', Dart wrote later on. Almost everybody would have taken the skull for a chimpanzee skull, but Dart knew that he was after something special. He had something of a scientific obstructionist about him. Probably he was attracted to the fact that he could eliminate some of the established ideas of his time. One of those was that such a discovery came from the wrong part of the world. One believed that anything of importance had to have taken place in Europe. According to white, European man we had to originate from Europe. 'We couldn't possibly come from Africa, now could we? Look at how primitive Africa is'. It was highly unlikely that man's origin should be sought after on the large, 'black' continent.
There was another surprise in the chest. Within the limestone there was a small skull. 'No clover worked with more love nor greater carefulness on a jewel of incalculable value', Dart wrote. Four weeks later the face appeared from the limestone. Dart studied the teeth and, to his great surprise, he saw that the canine tooth, the eye tooth, was as small as that of a human being! And not large and tusklike as that of a chimpanzee or gorilla. The skull had a complete temporary set of teeth, a set of milk teeth which was still in the process of erupting. The skull consisted of an almost complete front, a lower jaw with teeth and the right part of the brain pan. In the brain pan limestone had formed deposit that had taken the shape of the original contents, as a result of which an endocast had developed. This fitted exactly and so a small child's skull came into being. It was a revelation to him. 'In a wink of an eye I saw that the replica I was holding in my hand had three times the brain volume of a baboon', Dart declared. At a given moment he noticed something unexpected. Taking into account the shape of the skull basis, the head balanced on a vertical spinal column. It did not hang forward on an aslant spinal column as it does concerning animals walking on four legs instead of two. So it walked upright. It was an outstanding embodiment of the missing link between non-human animals and man. He must have thought of a statement of Charles Darwin in the nineteenth century when he predicted that Africa would appear to be the cradle of mankind. Dart named the fossil the' Taung skull', after the region of origin.
He wrote an article about his findings and sent it to England, to the famous magazine Nature. The editor had his doubts since younger small man-apes show bigger similarities with man than their parents. So the risk of mistakes was considerable. In England the general opinion was that Dart had not produced irrefutable evidence. A child didn't count as evidence. One would only be willing to listen in case he found an adult version. The general tendency was to want to leave everything as it was. 'We have Piltdown, haven't we? ', was used as an argument to support this attitude. This was a very old fossil, which appeared to be modern. Moreover, Piltdownman confirmed Britain's superiority as well as the existing racist prejudices towards, for example, Africans. Dart's discovery was threatening even though the Britons insisted that Piltdown and not Taung was the missing link.
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fig 2.6.3:
Robbert Broom |
Finally, Dart did find someone who agreed with him, Robert Broom, who resided in Africa. During his first visit to Dart Broom knelt in front of the skull of Taung to honour the fossil. Broom was a physician, had studied fossils of marsupials in Australia and was well-known worldwide as an expert in the field of mammallike reptiles. He investigated the Taung skull as well and came to the conclusion that the interpretation of Dart had been correct. Broom was determined to find prove which would confirm Dart's discovery. He started a search for an adult version of the child of Taung. Thus, the hunt for the Australopithecus africanus proceeded unabatedly. Together with some of Dart's students Broom visited the limestone sediments of Sterkfontein in the neighbourhood of his residential town. They soon found fragments of fossils. On the age of eighty, after more than ten years of persistent searching, Broom found a complete skull. It had the small brainvolume of a man-ape, but walked like a human being. Dart's skull of Taung no longer stood on its own. The awareness of it not just being a funny, little skull, but belonging to a complete community, a population, penetrated. New evidence accumulated and the tide turned.
Piltdown was guarded more strictly than the crown jewels. One could not study the specimen thoroughly until the fifties, as it was exhibited then. A certain got the opportunity to have a look at it. He soon noticed that something was not right. This specimen did not fit properly as a whole. When the conservator of the British Museum applied fluor dating (see also the background information about dating techniques) he discovered that the skull was ten thousand years older than the jawbone. A devastating publication proved that the lower jaw was of an orang-utan which had been remodelled into a human jaw. For forty years many experts had been cheated. Who were the offenders? No matter how intensely this was investigated, no proof was found. Why had this 'joke' lasted for so long? The Piltdownman had fitted in so well in the hopes of that time; an evolutionary missing link that combined those characteristics of man with those of the man-ape. This incident shows that what we expect to find can influence our interpretation of what we actually find.
As Piltdown was refuted, the child of Taung was cheerfully hauled in as our rightful ancestor. At last Africa proved to be the cradle of mankind. Over the years the African soil provided more and more indications concerning the mystery of human origin.
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