Now it seems that Lucy shared eastern Africa with another prehuman species, one that may have spent more time in trees than on the ground.

A 3.4-million-year-old fossil foot found in Ethiopia appears to settle the long-disputed question of whether there was only a single line of hominins — species more closely related to humans than to chimpanzees — between four million and three million years ago. The fossil record for that period had been virtually limited to the species Australopithecus afarensis, made famous by the 3.2-million-year-old Lucy skeleton.

Of perhaps more importance, scientists report in the journal Nature, published online Wednesday, the newfound foot not only belonged to a different species but also had evolved a distinctive mode of locomotion, which scientists described as “equivocal.” It clung to the trees and never adapted to terrestrial mobility outright.

The New York Times

Link:

http://www.nytimes.com/2012/03/29/science/african-foot-fossil-indicates-another-hominin-species-lived-with-lucy.html?pagewanted=all