Flores Hobbits: New analyses show the mini-humans as stranger & more primitive than previously thought

SCIENTIFIC AMERICAN staff editor and writer Kate Wong, in "Rethinking the Hobbits of Indonesia," SCIENTIFIC AMERICAN, November 2009, pp. 66-73, reports that new analyses show the mini-humans to be even stranger than previously believed, and hint that theories of human evolution need revision.

In 2004, Australian and Indonesian scientists excavating Liang Bua cave in Indonesia's Flores Island found bones of a miniature human species, formally named Homo floresiensis and nicknamed the "hobbit" for J.R.R. Tolkien's fictional creatures, that lived as recently as 17,000 years ago--far more recently than any other pre-sapiens hominids like Homo erectus or Homo neanderthalensis. Scientists initially suggested that Homo floresiensis was a dwarfed descendant of Homo erectus, a human ancestor with body proportions similar to our own and generally considered the first hominids to leave Africa. The "hobbits'" small size compared to H. erectus and modern humans was explained as an adaptation to island conditions.

New investigations, however, show that the "hobbits" were more primitive than researchers had thought--a finding that could could overturn prevailing assumptions about human evolution. The "hobbits" have been found to display features more primitive than those of Homo erectus, suggesting that H. erectus may not have been the first hominid to leave Africa. The Flores "hobbits" could have been a late-surviving relict population of a primitive hominid species that left Africa even before H. erectus. Homo erectus arose about 1,8 million years ago. while H. floresiensis may have appeared either shortly before or shortly after Homo habilis, who emerged about 2 million years ago.

To date, excavators have recovered the remains of about 14 individual "hobbits" from Liang Bua cave on Flores. Some of their features resemble those of apes and of australopithecines like the 3,2 million year old "Lucy." Other traits, however, resemble those of our own genus, Homo. The "hobbit" brain was about the size of a chimpanzee's. However, a virtual reconstruction, generated from CT scans of the interior of the braincase, indicates that despite its small size it had a number of complex, advanced features. Such features may help explain how a creature with a chimp-sized brain was able to make stone tools.

SCIENTIFIC AMERICAN, November 2009

(Submitted by T. Peter Park)