Hobbit-size skull holds surprises

By Dan Vergano, USA TODAY
Fans of The Lord of the Rings may be interested to know that a remote Indonesian island has yielded the remains of pint-size people, a surprising new human species that paleontologists say lived just 18,000 years ago.

In fact, scientists have nicknamed the new creature “Hobbit” after the diminutive folks in the famed J.R.R. Tolkien trilogy. Fiction aside, the discovery reported today by an Australian paleontology team is a big deal, challenging decades of human-origins research.

Buried amid scattered stone tools and the bones of pygmy elephants at Liang Bua cave on the eastern Indonesian island of Flores were the skeletal remains of a female belonging to the species that the discoverers have formally named Homo floresiensis.

In todays Nature journal, the team led by Peter Brown of Australias University of New England describes the being as a human relative, or hominid, that stood less than 40 inches tall. Except for a snout, she had a human face and a brain one-third the size of ours. She was older than 30, judging from her worn teeth and bone structure. Though like modern humans in some respects, she also resembled ancient species.

“Probably this is one of the most important discoveries in hominid paleontological history,” says University of Pittsburgh paleontologist Jeffrey Schwartz. “This is just about the wildest thing anyone could have discovered.”

Browns team believes that Hobbit is an example of island dwarfism, the widely observed tendency of isolated species to evolve toward smaller sizes because they are separated from mainland predators. The scientists suggest that the species started as an offshoot of Homo erectus, a human ancestor dating to 1.8 million years ago, that reached Flores by boat and eventually got smaller, hunting pygmy elephants and dodging Komodo dragons.

These beings must have been reasonably smart, “as they were manufacturing sophisticated stone tools, hunting pygmy elephants and crossing at least two water barriers to reach Flores,” says study co-author Richard Roberts of the University of Wollongong. “The latter two activities must surely have been group activities, which implies communicative skills and use of language … all with a brain the size of a grapefruit.”

Indeed, the brain size of H. floresiensis is most like those of our ancestors who lived more than 3 million years ago. The ratio of brain size to body mass resembles that of present-day chimps.

“The idea of linear progress in brain size throughout human evolution has been the one steadily held idea in the field for the last few decades,” says Rick Potts, head of the Human Origins Program at the Smithsonian Institution. “This is a big shot at that idea.”

Since submitting the Nature paper, the discovery team has uncovered parts of five to seven other individuals of the same stature at the cave, Brown says.