EARLY humans may have taken a different route out of Africa than previous evidence suggested, according to researchers.
The Nile Valley is widely believed to be the most likely route out of sub-Saharan Africa for early modern humans 120,000 years ago.
But a team at the University of Bristol has challenged this view in a paper published in the Proceedings of the Nat
ional Academy of Sciences.
Wetter conditions reached a lot further north than previously thought, providing a wet "corridor" through Libya for early human migrations, the study says.
While it is widely accepted modern humans originated in sub-Saharan Africa 150,000 to 200,000 years ago, their exit route across the arid Sahara remains controversial. The Sahara covers most of north Africa and to cross it on foot would be a serious undertaking, even today, with the most advanced equipment, the study says.
Well-documented evidence showed there was increased rainfall across the southern part of the Sahara during the last interglacial period – 130,000 to 170,000 years ago.
The Bristol University team, with collaborators from the universities of Southampton, Oxford, Hull and Tripoli in Libya, investigated whether these wetter conditions had reached further north than previously thought.
Anne Osborne, from Bristol University's department of earth sciences and the lead author on the paper, said: "Space-born radar images showed fossil river channels crossing the Sahara in Libya, flowing north from the central Saharan watershed all the way to the Mediterranean."
She went on: "Using geochemical analyses, we demonstrated that these channels were active during the last interglacial period, providing an important water course across this otherwise arid region."
The full article contains 282 words and appears in The Scotsman newspaper.
