Brainfirsttheories of human evolution

The first fossil human specimen was a Neanderthal child's skull found in Belgium in 1828, but its importance was not realized. The first skeleton was found in 1856 in Germany, a slouched and injured specimen, named Neanderthal man after the Neander Valley where it was found. This poor individual became the type 'cave man', our brutish forebear, coarse of limb, hairy of body and small of brain. He grunted at his fellows, tore raw meat from the bones of prey animals, dragged his wife along by her hair and huddled miserably in caves to keep warm.

Older human remains, found in 1891 in Java, were hailed as the 'missing link' and named Pithecanthropus erectus (now Homo erectus), a primitive form. Key evidence for the 'brain-first' theory came in 1912 when a remarkable skull was found by an amateur, Charles Dawson, in southern England, at the village of Pilt-down.The skull (Figure 11.7(a)) showe d a large brain of modern proportions, but the jaw was primitive, with ape-like teeth. This specimen was a godsend to the leading anthropologists of the day, the true 'missing link',

Fig. 11.7 Two controversial hominid skulls of the early twentieth century: (a) Piltdown man,found in 1912,and subsequently shown to be a hoax; (b) the first skull of Australopithecus africanus, the Taung child, reported in 1925. (Modified from photographs.)

clearly ancient, and yet a brainy forebear. Not only that, he was English!

In 1925, Raymond Dart announced an even more ancient skull from southern Africa, which he named Australopithecus africanus. It was a child's skull (Figure 11.7(b)), with a small ape-like braincase. Dart's new fossil was greeted widely with scepticism. Surely it was only a fossil ape, with nothing to do with our ancestry? Piltdown man proved the 'brain-first' model.

During the 1950s, two important chains of events overthrew the received wisdom on our ancestry. First, Piltdown man was shown to be a forgery—a recent human braincase with a modern orang-utan's jaw. The great champions of Piltdown man, the anatomists Elliott Smith and Arthur Keith, and the palaeontologists Arthur Smith Woodward and W. P. Pycraft,had died.

The second set of events took place in southern Africa, where many specimens of Australopithecus had been coming to light, and the weight of new material was proving harder to discount by the supporters of Piltdown. The unmasking of Piltdown in 1953 passed without any major public dispute, and scientific attention focused on African fossils of early, small-brained bipedal humans.

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