The Primitive Wrist of Homo floresiensis and Its Implications for Hominin Evolution

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21 September 2007 (Science Magazine) – And finally, the abstract of the homo floresiensis wrist study from Science Magazine. Subscription required for full access.

The Primitive Wrist of Homo floresiensis and Its Implications for Hominin Evolution
Matthew W. Tocheri, Caley M. Orr, Susan G. Larson, Thomas Sutikna, Jatmiko, E. Wahyu Saptomo, Rokus Awe Due, Tony Djubiantono, Michael J. Morwood, William L. Jungers

Whether the Late Pleistocene hominin fossils from Flores, Indonesia, represent a new species, Homo floresiensis, or pathological modern humans has been debated. Analysis of three wrist bones from the holotype specimen (LB1) shows that it retains wrist morphology that is primitive for the African ape-human clade. In contrast, Neandertals and modern humans share derived wrist morphology that forms during embryogenesis, which diminishes the probability that pathology could result in the normal primitive state. This evidence indicates that LB1 is not a modern human with an undiagnosed pathology or growth defect; rather, it represents a species descended from a hominin ancestor that branched off before the origin of the clade that includes modern humans, Neandertals, and their last common ancestor.

Wrist gives hobbit theory the flick

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21 September 2007 (ABC News in Science) – Here’s a news piece about the wrist study which sums up the news quite nicely in layman terms. There’s also a dissenting opinion about the study that’s also food for thought.

Wrist gives hobbit theory the flick
Anna Salleh

The hobbit had wrists more like those of non-human apes than those of modern humans, according to researchers who say their findings are more evidence that Homo floresiensis is a new species.

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Wrist bone study adds to Hobbit controversy

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20 September 2007 (Smithsonian Institution) – A new study on the wrist bones recovered from the homo floresiensis assembly adds extra weight to our Hobbit from Flores being an entirely new species rather than a sick, deformed human. There are a few other stories popping up today so stay tuned for more insights! It’s a really busy day at work, so hopefully I can post them all up by the end of the day.

Homo Floresiensis by SBishop
Homo Floresiensis skull, creative commons image by SBishop

New Research Sheds Light on “Hobbit” Smithsonian-led Study Published in Science

An international team of researchers led by the Smithsonian Institution has completed a new study on Homo floresiensis, commonly referred to as the “hobbit,” a 3-foot-tall, 18,000-year-old hominin skeleton, discovered four years ago on the Indonesian island of Flores. This study offers one of the most striking confirmations of the original interpretation of the hobbit as an island remnant of one of the oldest human migrations to Asia. The research is being published in the Sept. 21 issue of Science.

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Small skull, huge controversy

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c. 23 April 2007 (Research|Penn State) Research|Penn State, an online magazine by the Pennsylvana State University has an interesting feature-length article on Dr Bob Eckhart, who leads the charge in debunking the Hobbit myth. While SEAArch has covered plenty in the news about homo floresiensis, this article presents an in-depth look at the arguments against the Hobbit theory and is worth a read for anyone following the story.

Small skull, huge controversy

In October 2004, while working in his lab, Bob Eckhardt heard a report on National Public Radio: A team of archaeologists had unearthed bones of a three-foot-tall humanlike creature on the island of Flores in Indonesia. Based on the shape and size of the skull and other skeletal remains, the archaeologists, led by Michael J. Morwood of the University of New England in Armidale, Australia, claimed they had discovered a new species of human.

The diminutive biped had a cranium no larger than a chimpanzee’s, yet its bones had been found along with abundant stone tools. Radiocarbon dating of charcoal in the same stratum, along with luminescence dating of surrounding sediments, implied that the skeleton was only 18,000 years old. Considering other earlier archaeological finds on Flores, Morwood and his colleagues concluded that a new human species had evolved from a preceding population of Homo erectus that had been isolated for over 840,000 years on Flores, in the archipelago between Asia and Australia.

Eckhardt, a professor of developmental genetics and evolutionary morphology in Penn State’s department of kinesiology, added it up. Three feet tall. A tiny brain. Complex stone tools. Evolved in complete isolation in 40,000 generations. He says: “It just didn’t ring true.”

Eckhardt read the scientific papers, published in the British journal Nature, setting forth the findings and conclusions of Morwood’s group. “A lot of things didn’t make sense,” he says. “For instance, the overall height seemed to be off. I took the long-bone measurements from the paper and plugged them into standard regression formulas.” Where Morwood and colleagues estimated an overall height of 1.06 meters for their specimen, Eckhardt came up with figures ranging from 1.15 to 1.33 meters, with an average of 1.25 meters—more than seven inches taller than Morwood’s estimate. Eckhardt also wondered about the proximity of the small cranium to sophisticated stone tools, including points, perforators, blades, and microblades. Over a century of research by anthropologists has established a rough correlation between an increasing brain size and advances in stone-tool technology. The kinds of tools described in the Nature article matched those made elsewhere by Homo sapiens. Says Eckhardt, “It seemed very unlikely that a human with a chimp-sized brain would have invented such tools independently and in total isolation.”