Fossil may be new human species

CLEVELAND –  Ancient foot bones discovered in Ethiopia point to the existence of a previously-unknown human ancestor whose feet were specially adapted to tree climbing.

U.S. and Ethiopian scientists said that a 3.4 million-year-old partial foot found in Burtele, in the remote Afar region of Ethiopia, belonged to a prehuman who coexisted with the famous "Lucy" species, Australopithecus afarensis.

Scientists have long argued that there was only one prehuman species between three and four million years ago, but the fossilized foot bones provide the first indisputable evidence that at least two prehuman species with different modes of movement lived at the same time in East Africa....