Modern humans reached Arabia earlier than thought, new artifacts suggest

January 27th, 2011 in Other Sciences / Archaeology & Fossils
Assemblage C: Hand axe pre-form. For more information, please see figure S5 in the Supporting Online Material, and for Additional Assemblage C material, please see Figure 2 in the manuscript. Credit: Image © Science/AAAS


Assemblage C: Hand axe pre-form. For more information, please see figure S5 in the Supporting Online Material, and for Additional Assemblage C material, please see Figure 2 in the manuscript. Credit: Image © Science/AAAS

Artifacts unearthed in the United Arab Emirates date back 100,000 years and imply that modern humans first left Africa much earlier than researchers had expected, a new study reports. In light of their excavation, an international team of researchers led by Hans-Peter Uerpmann from Eberhard Karls University in Tubingen, Germany suggests that humans could have arrived on the Arabian Peninsula 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 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 along the Arabian coast approximately 60,000 years ago.

This new research, placing early humans on the Arabian Peninsula much earlier, will appear in the 28 January issue of Science.

Jebel Faya rockshelter from above, looking north, shows eboulis blocks from roof collapse and the location of excavation trenches. Credit: Image © Science/AAAS

The team of researchers, including lead author Simon Armitage from Royal Holloway, University of London, discovered an ancient human toolkit at the Jebel Faya archaeological site in the . It resembles technology used by early humans in east Africa but not the craftsmanship that emerged from the Middle East, they say. This 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 onto the Arabian Peninsula. Armitage calculated the age of the stone tools using a technique known as luminescence dating and determined that the were about 100,000 to 125,000 years old.

"These 'anatomically modern' humans — like you and me — had evolved in Africa about 200,000 years ago and subsequently populated the rest of the world," said Armitage. "Our findings should stimulate a re-evaluation of the means by which we modern humans became a global species."

The location of Jebel Faya, United Arab Emirates, along with key sites mentioned in the text. The dashed line represents the -120-m paleoshoreline, indicating the maximum exposure of land during marine lowstands. Credit: Image courtesy of Science/AAAS

Uerpmann and his team also analyzed sea-level and climate-change records for the region during the last interglacial period, approximately 130,000 years ago. They determined that the Bab al-Mandab Strait, which separates Arabia from the Horn of Africa, would have narrowed due to lower sea-levels, allowing safe passage prior to and at the beginning of that last interglacial period. At that time, the Arabian Peninsula was much wetter than today with greater vegetation cover and a network of lakes and rivers. Such a landscape would have allowed access into Arabia and then into the Fertile Crescent and India, according to the researchers.

"Archaeology without ages is like a jigsaw with the interlocking edges removed — you have lots of individual pieces of information but you can't fit them together to produce the big picture," said Armitage. "At Jebel Faya, the ages reveal a fascinating picture in which migrated out of much earlier than previously thought, helped by global fluctuations in sea-level and climate change in the Arabian Peninsula."

Provided by American Association for the Advancement of Science

"Modern humans reached Arabia earlier than thought, new artifacts suggest." January 27th, 2011. http://phys.org/news/2011-01-modern-humans-arabia-earlier-thought.html