Skull casts new light on ancestry
An unusual skull dug up in Africa has shed badly needed light on mankind's origins - in particular the debate over which primitive human species was the ancestor to modern humans.
Four parts of the 930,000
Skull casts new light on ancestry
An unusual skull dug up in Africa has shed badly needed light on mankind's origins - in particular the debate over which primitive human species was the ancestor to modern humans.
Four parts of the 930,000-year-old skull, from Olorgesailie, Kenya, were discovered by American researchers between June and August last year. The discovery was published in this week's edition of the journal Science.
The discovery has excited scientists because the African fossil record for this time - 1 million to 500,000 years ago - is, unusually for that continent, very poor.
Scientists aren't sure what species of human was living in Africa then, although the new skull has been nominally labelled Homo erectus.
"The cranium represents possibly the smallest adult or near-adult known between 1.7 million and 500,000 years ago," wrote the lead author of the Science paper, the Smithsonian Institution's Richard Potts.
"It retains features observed in larger Homo erectus individuals, yet shows a distinct suite of traits indicative of wide population variation in the hominins (early humans) of this period."
Scientists have long known that erectus left Africa and settled in Asia for hundreds of thousands of years before becoming extinct.
One view holds that erectus lived in Africa as well, eventually evolving into Homo sapiens.
The alternative view holds that early humans living in Africa were not erectus because the skulls found there are too different to Asian erectus.
Instead, they should be known as Homo ergaster, Homo antecessor or some other variant of Homo.
Dr Potts told The Age the new skull supports the theory that erectus lived in Africa also, even though the skull has features different to Asian erectus.
The variation in the fossil record from this time was not due to different human species, but variation within Homo erectus itself, he said.
"If you take the wide range of variation and divide it up finely into species, then Homo erectus is potentially confined to East Asia and is not an ancestor to Homo sapiens," he said.
"However, as suggested by our analysis... all the mid-Pleistocene variation may involve relatively sho