A Tiny Hominid With No Place on the Family Tree

By JOHN NOBLE WILFORD
Published: April 27, 2009

STONY BROOK, N.Y. — Six years after their discovery, the extinct little people nicknamed hobbits who once occupied the Indonesian island of Flores remain mystifying anomalies in human evolution, out of place in time and geography, their ancestry unknown. Recent research has only widened their challenge to conventional thinking about the origins, transformations and migrations of the early human family.

Indeed, the more scientists study the specimens and their implications, the more they are drawn to heretical speculation.

Were these primitive survivors of even earlier hominid migrations out of Africa, before Homo erectus migrated about 1.8 million years ago? Could some of the earliest African toolmakers, around 2.5 million years ago, have made their way across Asia?

Did some of these migrants evolve into new species in Asia, which moved back to Africa? Two-way traffic is not unheard of in other mammals.

Or could the hobbits be an example of reverse evolution? That would seem even more bizarre; there are no known cases in primate evolution of a wholesale reversion to some ancestor in its lineage.

The possibilities get curiouser and curiouser, said William L. Jungers of Stony Brook University, making hobbits “the black swan of paleontology — totally unpredicted and inexplicable.”

Everything about them seems incredible. They were very small, not much more than three feet tall, yet do not resemble any modern pygmies. They walked upright on short legs, but might have had a peculiar gait obviating long-distance running. The single skull that has been found is no bigger than a grapefruit, suggesting a brain less than one-third the size of a human’s, yet they made stone tools similar to those produced by other hominids with larger brains. They appeared to live isolated on an island as recently as 17,000 years ago, well after humans had made it to Australia.

Although the immediate ancestor of modern humans, Homo erectus, lived in Asia and the islands for hundreds of thousands of years, the hobbits were not simply scaled-down erectus. In fact, erectus and Homo sapiens appear to be more closely related to each other than either is to the hobbit, scientists have determined.

It is no wonder, then, that the announcement describing the skull and the several skeletons as remains of a previously unknown hominid species, Homo floresiensis, prompted heated debate. Critics contended that these were merely modern human dwarfs afflicted with genetic or pathological disorders.

Read the full article at: http://www.nytimes.com/2009/04/28/science/28hobbit.html?_r=1