Scientists say they found more bones in an Indonesian cave that offer 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 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.
Last year, 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, giving the discovery a fairytale quality.
If true, the discovery grafts a strange and tangled evolutionary branch near the very top of the human family tree.
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.
However, the researchers acknowledge that the Hobbit shares a bizarre and unexplained mixture of modern and primitive traits. For example, its long, dangling arms were thought to have belonged only to much older prehuman species that were confined to Africa.
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.