Science has another entry in their Origins: A History of Beginnings series. This time the entry concerns Kenyanthropus platyops. The fossil was the subject of a presentation at a meeting of the Royal Society in London .
Fred Spoor gave the presentation – which was a response to White’s criticisms:
In London, Spoor responded to such arguments with a new, detailed study. He concluded from computed tomography scans that the upper jaw, or maxilla, had suffered much less distortion than the rest of the cranium. So he focused on that bone, correcting for the distortion present. He measured distances among several “landmarks” on the maxilla, including the point at which the cheekbone attaches to it, the extent of its forward projection, and the orientation of its tooth sockets. He used the same landmarks on A. afarensis specimens, the roughly 4-million-year-old A. anamensis, later australopithecines, and modern humans, chimps, and gorillas. Then he crunched the measurements in a computer-assisted analysis called principal component analysis to reveal the variability among the specimens. The result: Kenyanthropus fell cleanly outside the range of variation in all the other samples. “Species diversity existed at 3.5 million years ago, and this justifies assigning a new taxon,” Spoor concluded.
White, also at the meeting, was skeptical.
Spoor’s study will be published in Philosophical Transactions of the Royal Society B: Biological Sciences in Spring 2010 and let’s hope it’s open access…