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'Hobbit' Clash Escalates: Follow-Up Study on 3-Foot Skeleton Aims to Bolster Claim of New Species, but Critics Still Fervent in Opposition

Posted on: Tuesday, 30 January 2007, 09:00 CST

By Bryn Nelson

What's a would-be hobbit to do?

In the latest chapter of a bitter scientific spat, an international research team has published a set of computer-aided brain images in support of the contested hypothesis that a "hobbit-like" skeleton from an Indonesian cave represents a new species rather than a developmentally stunted human.

Among the implications, the study may buttress the idea that the brains of some human-resembling hominids evolved by getting "better wiring" instead of getting bigger, according to lead author Dean Falk, chairwoman of the anthropology department at Florida State University in Tallahassee.

Au contraire, according to Robert Martin, a curator of biological anthropology at Chicago's Field Museum who pounced on nearly every facet of the new study, published today in the Proceedings of the National Academy of Sciences.

"What we're arguing is that this is not a new hominid species at all, but probably a modern human microcephalic," Martin said, referring to a broad group of congenital conditions all characterized by an abnormally small brain.

The often acrimonious back-and-forth, at times overshadowing the unusual specimen itself, illustrates the heat that can accompany the high-stakes quest to understand our origins despite a limited fossil record.

When a group of researchers announced in 2004 they had discovered a set of 18,000-year-old remains on the Indonesian island of Flores that measured just 3 feet in height and possessed a diminutive skull despite belonging to an adult, the battle over the origins of Homo floresiensis officially began.

In the three years since then, the scientific equivalent of a backyard brawl has broken out among rival groups and featured accusations of sloppiness, selective data mining, lack of expertise, withholding data and hypocrisy. Even the sex of the fossil remains contested, with Martin referring to it as a "he" and Falk's group describing it as a woman.

Bill Jungers, chairman of Stony Brook University's anatomy department, said he's agnostic on the gender issue, given the limited and conflicting skeletal cues. On the larger point, though, he's unequivocal: "I think this paper pretty much demolishes the notion that this is a microcephalic brain," he said. Jungers is not connected to the research.

In the study, Falk and her collaborators used CAT scans to fashion three-dimensional images revealing the shape, size and some limited physical features of the outer brain. Although variations exist, Falk said people with microcephaly tend to have a cerebellum that sticks out in the back and relatively narrow frontal lobes. From the gathered measurements, her team used two ratios to quantify those common features of microcephaly.

A data plot showed that the Flores fossil grouped with 10 normal human brains, despite its much smaller size, while that of a modern dwarf and an African woman with suspected microcephaly both grouped with nine microcephalic brains.

Martin dismissed the results by contending that Falk's group "played around" with their data until getting a desired answer.

"That's a silly argument," retorted Falk, who said she had answered Martin's "yelling and screaming" by simply quantifying widely accepted descriptions of microcephalic brains.

"We can go on until the cows come home," Martin said of the impasse. In the meantime, the original fossil discoverers have received permits to continue exploring the Indonesian cave, where other "hobbits" or humans -- female or male -- may yet have a thing or two to say about our highly unsettled past.

Source: Newsday, Melville, N.Y.

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