January 27, 2011. Copyright 2011, Graphic News. All rights reserved

Humans may have colonized world via Arabia

LONDON, January 27, Graphic News: Artifacts unearthed in the barren desert and hills of the United Arab Emirates date back more than 100,000 years and imply that modern humans first left Africa earlier than researchers had expected, a new study reports.

The timing and dispersal of modern humans out of Africa has been the source of long-standing debate, though most evidence has pointed to an exodus along the Mediterranean Sea or Arabian coast approximately 60,000 years ago.

Now, Simon Armitage of the Royal Holloway University of London and an international team of researchers are sparking interest and controversy by suggesting that humans arrived in eastern Arabia as early as 125,000 years ago -- directly from Africa rather than via the Nile Valley or the Near East, as researchers have suggested in the past.

The debate centers on a collection of stone tools excavated from the Jebel Faya archaeological site in the United Arab Emirates. The toolkit includes relatively primitive hand-axes along with a variety of scrapers and perforators, and its contents imply that technological innovation was not necessary for early humans to migrate into Arabia.

“The tools were found buried within sediments consisting of rock and sand” explained Armitage, “Because of this, we can use optically stimulated luminescence dating to work out how long ago the tools were buried and therefore how old they are.” They have been dated to about 125,000 years ago.

The researchers, writing in the January 27 edition of the journal Science, also analysed historical sea-level and climate change records for the region and determined that the Bab al-Mandab Strait, which separates Arabia from the Horn of Africa, would have dried up enough to allow safe passage during the last interglacial period.

“There is a possibility that the straits were passable at low tide”, said Dr. Hans Peter Uerpmann of the University of Tubingen in Germany. “They could maybe have walked across, [or] they could have used rafts or boats which they certainly could make at that time.”

Other researchers are enthusiastic about the Jebel Faya discovery but cautious about the conclusions: “One site does not confirm the ‘Out of Africa via Arabia’ hypothesis,” said archaeologist Mark Beech, of Britain’s University of York.

Uerpmann agrees, saying that fossil bones are needed “before we can be absolutely sure” that the tools were made by Homo sapiens.
/ENDS