New theory provides alternate route “Out Of Africa” for early humans
While it is widely accepted that modern humans originated in sub-Saharan Africa 150-200 thousand years ago, their route of dispersal across the hyper-arid Sahara remains controversial. The widely held belief is that the Nile valley was the most likely route out of sub-Saharan Africa for early modern humans 120,000 year ago.
In a new paper in the Proceedings of the National Academy of Sciences, a team led by the University of Bristol shows that wetter conditions reached a lot further north than previously thought during the last interglacial period (130-170 thousand years ago), providing wet corridors through Libya for early human migrations. These corridors rivalled the Nile Valley as potential routes for early modern human migrations to the Mediterranean shores.
Isotopic composition measurements of snail shells taken from two sites in the fossil river channels have a distinctly volcanic signature different from the other rocks surrounding the sites. Water flowing from the volcanic mountains of the Saharan watershed is the only possible source of this signature, according to the researchers.
The similarities between Middle Stone Age artefacts in places like Chad and the Sudan, with those of Libya, strongly support this theory of early human migration.
