Wednesday, April 04, 2007

Leakey & his transitionals


From here.

The fragmented skull Dr. Bromage reconstructed was originally discovered in Kenya in 1972 by Dr. Leakey, who reassembled it by hand and dated it at nearly three million years of age, an estimate revised to 1.9 million years by scientists who later discovered problems with the dating.

"Dr. Leakey produced an intrinsically biased reconstruction based on erroneous preconceived expectations of early human appearance that violated principles of craniofacial development," said Dr. Bromage, whose reconstruction, by contrast, shows a sharply protruding jaw and, together with colleague Francis Thackeray, Transvaal Museum, South Africa, a brain less than half the size of a modern human's.

These characteristics make the 1.9 million-year-old early human skull more like those of two archaic, apelike hominids, Australopithecus and early Paranthropus, living at least three million and 2.5 million years ago, respectively.

Dr. Bromage developed his reconstruction according to biological principles holding that the eyes, ears, and mouth must be in precise relationship to one another in all mammals.

"Because he did not employ biological principles, Dr. Leakey produced a reconstruction that could not have existed in real life," Dr. Bromage concluded.
Figures..

Searching for transitionals often leads to desperation. Tweak those suckers a bit, and you can make them work for ya.