New Analysis Suggests Homo Floresiensis Not A New Species

The latest chapter in the ongoing debate over whether or not the remains currently being classified as H. Floresiensis do in fact represent a previously unknown hominin living on the island of Flores in Indonesia, 15,000 years ago.

Science Daily - Flores bones show features of Down syndrome, not a new 'Hobbit' human

Now detailed reanalysis by an international team of researchers including Robert B. Eckhardt, professor of developmental genetics and evolution at Penn State, Maciej Henneberg, professor of anatomy and pathology at the University of Adelaide, and Kenneth Hsü, a Chinese geologist and paleoclimatologist, suggests that the single specimen on which the new designation depends, known as LB1, does not represent a new species. Instead, it is the skeleton of a developmentally abnormal human and, according to the researchers, contains important features most consistent with a diagnosis of Down syndrome.

The research team makes a compelling argument. First they say the cranial volume was underestimated. The new estimates put the volume within the accepted range for an Australomelanesian individual with Down's Syndrome:

In the first place, they write, the original figures for cranial volume and stature are underestimates, "markedly lower than any later attempts to confirm them." Eckhardt, Henneberg, and other researchers have consistently found a cranial volume of about 430 milliliters (26.2 cubic inches).

"The difference is significant, and the revised figure falls in the range predicted for a modern human with Down syndrome from the same geographic region," Eckhardt said

They also point to the asymmetry of the skull which is an indicator of developmental disorders:

The first indicator is craniofacial asymmetry, a left-right mismatch of the skull that is characteristic of this and other disorders. Eckhardt and colleagues noted this asymmetry in LB1 as early as 2006, but it had not been reported by the excavating team and was later dismissed as a result of the skull's being long buried, he said.

As for the short thighbones:

LB1's short thighbones not only match the height reduction seen in Down syndrome, Eckhardt said, but when corrected statistically for normal growth, they would yield a stature of about 1.26 meters, or just over four feet, a figure matched by some humans now living on Flores and in surrounding regions

With conflicting findings over the years from several well-regarded researchers, this isn't likely to be the last word on H. Floresiensis but these findings are something worth considering.

Someone beat you to this, sorry man.

Flores bones show features of Down syndrome, not a new 'Hobbit' human

a reply to: ThisIsMyRifle

Ah, posted it while I was putting together my post. Thanks for the heads up!