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WASHINGTON - The tiny woman dubbed the Hobbit who lived 18,000 years ago on a remote Indonesian island deserves to be deemed a new human species and not a deformed modern human as sceptics assert, researchers said today.
In the latest salvo in a heated scientific shootout, an international team led by Florida State University anthropologist Dean Falk compared the Hobbit's skull to those of nine people with microcephaly, a rare condition in which the head is abnormally small due to improper brain development.
They concluded the one metre adult woman had a highly evolved brain, unlike that of a microcephalic person, confirming she belongs to the proposed extinct species Homo floresiensis, closely related to modern Homo sapiens.
"Lo and behold, it doesn't look anything like a microcephalic. In fact, it's antithetical," Falk said in an interview, rebutting scientists like primatologist Robert Martin of the Field Museum in Chicago who suggest the skull came from a person with microcephaly.
A previous study by Falk had been criticised because it compared the Hobbit, with a brain a third the size of modern people, to just a single microcephalic skull.
Martin remained unconvinced. "My gut feeling is what they (Falk's team) did is just played around with the measurements until they got something that suited them," Martin said.
Martin said the new study was flawed, questioned whether Falk's team knew enough about microcephaly and insisted the question of a separate species is unresolved.
The study appears in the Proceedings of the National Academy of Sciences. Michael Morwood, part of the group that discovered the remains, is a co-author.
Scientists in 2003 found the bones in a cave on the island of Flores east of Bali, contending they were a previously unknown species living at a time the species Homo sapiens was thought to have been the world's only human inhabitant.
These little people -- bones from several other individuals also were found -- lived in a wondrous place populated by strange animals like pygmy elephants and large rodents. In this isolated locale, evolutionary forces stemming from limited resources may have pushed some inhabitants toward dwarfism and others toward gigantism.
Tools and evidence of fire were found near the bones of the adult female, dubbed the Hobbit after the small people in the writings of J.R.R. Tolkien.
Falk's team compared three-dimensional, computer-generated reconstructions of the brain of the Hobbit to those of nine microcephalics from all over the world and 10 normal people.
Two features in the frontal lobes and a structure called the cerebellum separated the two groups, with the Flores woman fitting in with normal humans, not microcephalics, the study found. But she was unlike modern humans in four other features distinguishing her from Homo sapiens, crying out for recognition as a separate species, the researchers said.
Falk said the origin of this new species is now the key question, adding she is open to the possibility it descended from Australopithecenes, ape-like human ancestors, or was a dwarf form of the extinct species Homo erectus.
Martin said it is possible it is a new species. "But the other strong possibility is that this is actually just a pathological modern human," Martin added.
"At the end of the day, hopefully, the truth will come out," Martin added. "And I'm not mad enough to think I'm right about everything. But there are ways of doing it and ways of not doing it."
- REUTERS