Tuesday, August 22, 2006

The Homo hobbitus saga continues. . . Indon Hobbit 'was disabled caveman'
Nicknamed the hobbit, the 1m skeleton was by far the smallest ever found, with a brain the size of a grapefruit.

However, a new study contends the remains probably belonged to an early human suffering from microcephaly, a condition that causes an abnormally small head and other deformities, London's Sunday Times reports.

The paper quotes a report in the Proceedings of the National Academy of Sciences, one of America's most respected scientific institutions, as suggesting the initial evaluation of the remains was flawed.

“The skeletal remains do not represent a new species, but some of the ancestors of modern human pygmies who live on the island today,” the report said.

More at Time:
The PNAS team closely examined the one almost complete skull unearthed at Flores and say they found no evidence that it was belonged to anyone but a modern human. The skull was shaped asymmetrically, which the researchers argued was due to the effects of microcephaly. They also say that many of the features of the jaw and teeth cited as evidence that it belonged to a separate species-such as the lack of a chin-could be seen among modern Flores pygmies. It's that last part — the fact that a population of pygmies can still be found living just a stone's throw away from the Liang Bua cave where the original bones were found — that helped clinch the argument for Robert Eckhardt, a developmental geneticist at Penn State and another author of the PNAS paper. "If you look throughout the area, there are plenty of populations where the average male is under a meter and a half [4'11''] and females are shorter," he says. "If the people there are short now, so were the people who lived there 20,000 years ago."

And at Eurekalert.

And Hawks has a lengthy discussion of the actual paper. Some of his conclusions:
I completely accept the argument that LB1 is pathological. A corollary is that the skeleton cannot be a convincing type specimen for a new species.

But this isn't only about LB1: there are the other small specimens. This paper makes clear that none of the features of the LB6/1 mandible are outside the range of local peoples. This is not a case of two specimens that must share some rare pathology; the paper argues that they are two specimens that share a regionally-common suite of characteristics. They aren't, in other words, unusual.