for National Geographic News
The proof is in the wrist: The "hobbit" human found on the Indonesian island of Flores is indeed a unique species, not a diseased modern human, a new bone analysis suggests.
Since the discovery of the hobbit's remains was announced in 2004, researchers have debated whether the find represent a new, small-bodied species called Homo floresiensis or a diseased modern human.
Much of the debate has centered on the hobbit's grapefruit-size skull.
Some researchers hold that the brain case is that of a modern human with a genetic disease that causes small brains.
Other researchers conclude it looks nothing like a diseased modern human but instead represents a new species.
The new study steps outside the brain box and finds resolution in the wrist.
"Their wrist bones don't look anything like wrist bones that modern humans and Neanderthals have," said Matthew Tocheri, a paleoanthropologist at the Smithsonian Institution in Washington, D.C.
The wrist bones are more primitive, he said, like those of gorillas, chimpanzees, and other early human ancestors. This suggests the hobbit represents a lineage that appeared before the modern wrist evolved.
"This is basically something that has descended from an ancestor that probably lived sometime between one and three million years ago," Tocheri said.
Knowing who that ancestor is must wait until wrist bones for other ancestors are found, he noted. Possibilities include Homo erectus and the more primitive australopithecines.
Tocheri is the lead author of the new study, which appears in tomorrow's issue of the journal Science. Co-authors include Australian, U.S., Canadian, and Indonesian researchers.
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