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Pacific Island Fossils Reignite ‘Hobbit’ Species Debate

BY Admin  March 14, 2008 at 5:05 PM EST

Lee Berger in Palau Cave: Photo Nat. Geo. Soc.

The Flores skeleton, called LB1 and nicknamed “hobbit,” was unearthed in 2003. The bones, which date from about 18,000 years ago, suggested the smallest human ever found — only a little more than one meter tall. The skeleton had other unusual features: a tiny head less than one-third the size of a modern human; a small chin; and unusually shaped limbs, among others.

Together, these features were enough to convince some researchers that the skeleton belonged to an entirely new species of human, which they named Homo floresiensis. The researches postulated that the species would have lived at the same time as modern humans, Homo sapiens, on Flores, but then eventually died out.

Many researchers, however, remain unconvinced. They believe that the “hobbit” was simply a member of a population of very small Homo sapiens, and that LB1 had some genetic disease, such as microcephaly, that would explain its small head and other irregularities.

Over the past several years, researchers have analyzed the wrist, shoulder, brain size and more of the fossil, looking for answers — but the field remains divided, sometimes bitterly.

“I think whenever major discoveries regarding the human record are made, you always get this naysaying,” said anthropologist Dean Falk, a proponent of the separate-species theory who has studied LB1′s skull. “It’s a knee-jerk reaction.”

But many others disagree — and now point to the newly-discovered Palau fossils as evidence.

The fossils, remains of a population of small-bodied people who lived between 1,000 and 3,000 years ago, share many of LB1′s unusual traits–they are very small and they have small chins and unusual teeth, among other traits. However, other features, such as proportionally-sized heads, make them recognizably Homo sapiens, says paleoanthropologist Lee Berger, who discovered the fossils.

Scientists who believe that LB1 was simply a small Homo sapien with a genetic disease say that the discovery of a nearby population of very small humans provides evidence in their favor.

“The Berger paper is great because it shows that in the region you have small people with normal-sized brains, and you don’t have to posit a new species to explain them,” Pennsylvania State University anthropologist Robert Eckhardt, a proponent of the hobbits as Homo sapiens theory, told the New York Times. “It’s incredibly strong support for our hypothesis.”

But Falk and other proponents of the separate-species theory say the new fossils are irrelevent. They also question Berger’s methods — he examined many fossil fragments from different individuals, instead of having a full skeleton to work with. Berger says he is “surprised” by the criticism, since many species are described on the basis of fossil fragments rather than full skeletons.

Finding these fossils was a stroke of luck for Berger, of the University of Witwatersrand in South Africa. He was on vacation with his wife in Palau — a destination she’d chosen specifically because the young island seemed unlikely to contain fossils, he says.

But on a kayak trip on their last day, a guide mentioned a nearby cave with old bones, and Berger couldn’t resist taking a look. He usually studies much older fossils — the next-youngest he’s looked at was about 75,000 years old, and in comparison the new finds “are practically still alive,” he says. But he realized right away that he’d found something worth a return trip.

“The most striking thing was a little face that fit into the palm of my hand,” he said. Several weeks and one National Geographic Society grant later, he was back, this time with a research team in tow.

The find provides evidence for the field’s ongoing debate over the “hobbit,” but the debate is far from settled, researchers say.

“It’s a complicated problem,” University of Wisconsin anthropologist John Hawks told Wired magazine. Hawks, who edited the Berger paper, hasn’t made up his mind about Homo floriensis. “The simple answer is that we lack definitive information that would settle it.”