New Human Ancestor Found

A skull uncovered in Kenya establishes a new genus in the human family tree and challenges current thinking on human ancestry.

Homo sapiens and other upright-walking primates, or hominids, were thought to have evolved from a single ancestral genus, Australopithecus, known best by a partial skeleton discovered in 1974 nicknamed Lucy. Early hominids evolved progressively more humanlike features, such as longer limbs, larger brains, and smaller teeth, and ultimately became modern men and women.

The find shows that recent humans, like all modern animals, are simply a surviving lineage of many others that died out long ago, and that our evolutionary tree looks more like a bush. So did modern humans evolve from Lucy or "Flat-face"? Leakey speculates that we probably didn't evolve from either, but from an ancestral group that has yet to be uncovered.

Meave Leakey, paleoanthropologist, center, with Academy Anthropology Chair Nina Jablonski and Academy Director of Research Dave Kavanuagh at the Herbst Theater on March 22, 2001 where Dr. Leakey first presented her discovery to the public. Photo by Dong Lin.

But now researchers led by Meave Leakey from the National Museums of Kenya have found the skull of a hominid which lived during Lucy's time, about 3.4-3.5 million years ago, but clearly belonged to a separate lineage. The skull, given the new genus Kenyanthropus, which means "the flat-faced man from Kenya," has a flatter, more humanlike face and smaller molars than Lucy. Never before have these features been seen in one individual.