The timing and dispersal（分散，传播） of modern humans out of Africa has been the source of long-standing debate, though most evidence has pointed to an exodus（大批的离去） 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, which is published by AAAS, the nonprofit science society.

The team of researchers, including lead author Simon Armitage from Royal Holloway, University of London, discovered an ancient human toolkit（工具包） at the Jebel Faya archaeological site in the United Arab Emirates. It resembles technology used by early humans in east Africa but not the craftsmanship（技术，技艺） that emerged from the Middle East, they say. This toolkit includes relatively primitive hand-axes along with a variety of scrapers and perforators（穿孔器） , 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（发冷光） dating and determined that the artifacts（史前古器物） 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."

Uerpmann and his team also analyzed sea-level and climate-change records for the region during the last interglacial period（间冰期） , 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 early humans access into Arabia and then into the Fertile Crescent and India, according to the researchers.

"Archaeology without ages is like a jigsaw（拼图玩具，线锯） with the interlocking（连锁的） 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 modern humans migrated out of Africa much earlier than previously thought, helped by global fluctuations（波动，起伏） in sea-level and climate change in the Arabian Peninsula."