Washington: The fossilised skulls of two adults and one child discovered in the afar region of Eastern Ethiopia have been dated at 160,000 years, making them the oldest known fossils of modern humans or Homo Sapiens.

The skulls dug up near a village called Herto, date to the period when biologists using genes to chart human evolution predicted that a genetic "Eve" lived somewhere in Africa and gave rise to all modern humans.

"We've lacked intermediate fossils between pre-humans and modern humans, between 100,000 and 300,000 years ago, and that's where the Herto fossils fit," said paleoanthropologist Tim White, professor of integrative biology at the University of California, Berkeley.

The international team led by White and his Ethiopian colleagues also unearthed skull pieces and teeth from seven other hominid individuals, hippopotamus bones bearing cut marks from stone tools, and more than 600 stone tools, including hand axes.

They lived long before most examples of the Neanderthal man, proving beyond a reasonable doubt that Homo Sapiens did not descend from these short, stocky creatures. More like cousins, Neanderthals split off from the human tree more than 300,000 years ago and died out about 30,000 years ago, perhaps driven to extinction by modern humans.

Because the Herto fossils represent a transition between more primitive hominids from Africa and modern humans, they provide strong support for the hypothesis that modern humans evolved in Africa and subsequently spread into Eurasia. This premise goes against the theory that modern humans arose in many areas of Europe, Asia and Africa from other hominids, who had migrated from Africa at a much earlier time.

Scientists, tracking evolution through changes in mitochondrial DNA passed down from mother to daughter, have estimated that humans derive their mitochondrial genes from an ancestral mother nicknamed "Eve", living in Africa about 150,000 years ago.

Previously found fossils were younger, picked up from sites scattered around Africa, often poorly dated and incomplete and included fossil skull fragments from Klasies River Mouth in South Africa and Middle Eastern fossils from Qafzeh and Skhul dating from 90,000 to 130,000 years ago.

While these previous discoveries appear also to be Homo Sapiens, the new finds from Herto are older, well dated and more complete without sharing characteristics of more primitive human ancestors such as Homo Erectus or the Neanderthals.

The mortuary rituals of the Herto people differ from those of earlier hominids, some of whom cut flesh from skulls, but apparently did not polish or decorate them with scratch marks.

Modifications like those seen in the Herto skulls have been recorded by anthropologists from societies, including some in New Guinea, in which the skulls of ancestors are preserved and worshipped.

The team also recovered more than 640 stone artefacts, though they estimate that the entire Herto area contains millions of such artefacts: hand axes, flake tools, cores, flakes and rare blades.

ANI