Jawbone hints at new human species

A 300,000-year-old jawbone discovered in a cave in eastern China could represent a new branch of the human family tree. The bone bears a curious mix of modern and archaic features: it’s thick along the jawline, a feature shared with early human species, and lacks the true chin of Homo sapiens. But the side of the mandible is more reminiscent of that of modern humans. The finding deepens the mystery of which ancient human species inhabited East Asia during the Pleistocene, and whether any of them could be ancestors of modern humans.