Scientists say they have found more bones in an Indonesian cave that offer additional evidence of a second human species – short and hobbit-like – that roamed the Earth the same time as modern man.
But the vocal scientific minority that has challenged that conclusion since the discovery of Homo floresiensis was announced last year remains unconvinced.
The discovery of a jaw bone, to be reported in today’s issue of the journal Nature, represents the ninth individual belonging to a group believed to have lived as recently as 12,000 years ago. The bones are in a wet cave on the island of Flores in the eastern limb of the Indonesian archipelago, near Australia.
In 2004, scientists announced their original, sensational discovery of a delicate skull and partial skeleton of a female, nicknamed “Hobbit” and believed to be 18,000 years old. In addition, they found separate bones and fragments of other individuals ranging in age from 12,000 to 95,000 years old.
The findings have ignited a controversy unlike any other in the often-contentious study of human origins.
The tiny bones have enchanted many anthropologists who accept the interpretation that these diminutive skeletons belonged to a remnant population of prehistoric humans that were marooned on Flores with dwarf elephants and other miniaturized animals.
If true, the discovery grafts a strange and tangled evolutionary branch near the very top of the human family tree.
The conventional view of human evolution is that several types of primitive ape-like ancestors appeared and faded over a span of about 4.5 million years. Modern Homo sapiens developed about 100,000 years ago, and quickly overtook other large-brained competitors like Homo erectus and Neanderthals
Fully grown, Homo floresiensis would have stood about 3 feet tall, with a brain about the size of a chimpanzee.
Its discoverers, led by Australian anthropologist Michael Morwood of the University of New England, speculate it evolved from Homo erectus, which had spread from Africa across Asia. They attribute its small size to its isolation on an island.
A vocal scientific minority insists the Hobbit specimens do not represent a new species at all. They believe the specimens are nothing more than the bones of modern humans that suffered from microencephaly, a broadly defined genetic disorder that results in small brain size and other defects.