A new study has found that humans may have first migrated out of Africa through Egypt — not Ethiopia, as was once believed. Genetic analysis of people living in Ethiopia and Egypt today has revealed that ancient people carried out a migration through Egypt long ago, headed toward the north.
Ancient humans first evolved in sub-Saharan Africa roughly 200,000 years ago, according to the best scientific research available. Their exodus from Africa took place between 70,000 and 130,000 years before our own time. The route these groups took has however been a subject of intense debate for decades. It is not even certain whether this mass migration happened in a single event, or came in waves.
"Two geographically plausible routes have been proposed: an exit through the current Egypt and Sinai, which is the northern route, or one through Ethiopia, the Bab el Mandeb strait, and the Arabian Peninsula, which is the southern route," said Luca Pagani from the Wellcome Trust Sanger Institute and the University of Cambridge.
The genomes of Eurasians were found to be more closely matched with Egyptians than Ethiopians. Analysis of the DNA shows that modern-day residents of Asia and Europe split from Egyptians 55,000 years ago — 10,000 years after branching off from Ethiopians. These populations departed from the genetic tree of west Africans 75,000 years before our own time.
This provides evidence for the theory that most early humans left Africa by traveling through Egypt, and not Ethiopia.
"The most exciting consequence of our results is to have unveiled an episode of the evolutionary past of all Eurasians, therefore potentially improving the knowledge of billions of people on their deep biological history," Pagani said.
Modern-day Israel would have been close to the path taken by ancient migrants along the northern route. An archaeological find made in that nation, announced this January, revealed the presence of modern humans there 55,000 years ago. All modern-day humans, except those living in Africa, contain some trace of genetic code left over from Neanderthals. Populations of those hominids would have been living along the northern route at the time in which one or more migrations may have taken place.
No genetic evidence has yet been found suggesting early humans traveled through Ethiopia on their way out of Africa. This does not mean that such a movement did not take place, and evidence of such population shifts in the distant past may be found during future research examining people of Oceania.
Analysis of the migration out of Africa was profiled in the American Journal of Human Genetics (AJHG).
Photo: Zephyrance Lou | Flickr
