At least three different human species co-existed in Africa between 1.78 and 1.95 million years old, according to an analysis of fossils uncovered in northern Kenya. The finding, published this week (August 8) in Nature, supports suspicions that a human skull found in 1972 was in fact a distinct species from Homo habilis and Homo erectus. The skull had a large brain and flat face compared to other known human fossils of the time, and was given the name Homo rudolfensis, but with no other fossils to support its classification as a new species, the field remained divided.
But the new fossils—a face and two jawbones with teeth—suggest that H. rudolfensis was indeed a distinct human species, which lived alongside other ancient human species some 2 million years ago.
"Our past was a diverse past," Meave Leakey of the Turkana Basin Institute in Nairobi, who led the study, told BBC News. "Our species was evolving in the same way that other species of animals evolved. There was nothing unique about us until we began to make sophisticated stone tools."