Ancient skull tells tale of human origins

A skull dating from 36,000 years ago supports the idea that modern humans originated in sub-Saharan Africa, says a report published Friday in the journal Science.

The study was based on the Hofmeyr skull, found near the South African town of that name more than50 years ago.

First, the team dated the skull by measuring the amount of radiation absorbed by sand inside the braincase.

At just over 36,000 years, the skull "fills a significant void in the human fossil record of sub-Saharan Africa from the period between about 70,000 and 15,000 years ago," researchers said in arelease.

Then, using three-dimensional measurements, the skull was compared with recent sub-Saharan Africans and European specimens dating from the same time period, the Upper Paleolithic.

The Hofmeyr skull matched the European examples, the researchers said.

Finding supports African emergence

That finding supports the idea that modern humans emerged from Africa and spread out, replacing the Neanderthals. The"out of Africa" theory predicted that there would be similarfossils from the two locationsfrom the same time.

"The skull from South Africa provides the first fossil evidence in support of this prediction," the researchers said.

The alternative "multiregional hypothesis" holds that some interbreeding took place between Neanderthals and early humans.

The study was headed by Frederick Grine from Stony Brook University in New York. The dating work was doneby Richard Bailey and colleagues at Oxford University.

Katerina Harvati of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, did the three-dimensional skull measurements and comparisons.