Three fossil remains dating back two million years discovered in Kenya, east Africa have supported the existence of diverse groups of early human ancestors belonging to genus Homo as claimed earlier in 1970s.

Researchers discovered a new partial skull and two jaw bones at Koobi Fora, badlands near Lake Turkana in Kenya suggesting that there was second Homo species that survived along with the early Homo erectus around the same period.

The new fossil remains has a flat face and relatively a large brain that is completely different from the modern humans belonging to the species of Homo sapiens. "Two species of the genus Homo, our own genus, lived alongside our direct ancestor, Homo erectus, nearly 2 million years ago," researcher Meave Leakey one of the study authors at the Turkana Basin Institute in Nairobi, Kenya, told LiveScience.

Homo erectus species was believed to be the primitive and direct ancestor of the modern humans, but researchers found fossil remains at the Olduvai Gorge in Tanzania in the 60s that was much older than the Homo erectus and was called as Homo habilis. Scientists have not been able to understand about the Homo habilis species as they could find very few fossils of the species.

With the discovery the new fossil remains, researchers suggest that the human ancestors are a diverse group. A skull named KNM-ER 1470 unearthed in Kenya in the 70s was found to belong to another early ancestor group called as Homo rudolfensis. The skull had a large brain than the fossil remains of species Homo habilis. This skull had been in the center of the debate for long as to where it fits in the human family tree.

However, the structure of the new fossil is said to have matched the KNM-ER 1470 skull.  The study showed evidence that east Africa was once a place for diverse early human species of the genus Homo

"This shows east Africa about 2 million years ago was quite a crowded place with many diverse species of early Homo," Fred Spoor, paleoanthropologist at the University College London and study author, told LiveScience.

The findings of the study are published in the journal Nature.