The Backflow into Africa

A 19th Century nobleman of Ethiopia -- the population most impacted by the backflow
A 19th Century nobleman of Ethiopia — one of the lands most impacted by the backflow

We all know Homo sapiens evolved in Africa and then spread across the rest of the world. But scientists have demonstrated that, starting around 5000 B.C.E., an astoundingly large group came back. This “backflow” brought so many people from Eurasia that today’s East Africans get as much as 25% of their genome from Middle Eastern ancestors. In other words, about a quarter of their ancestors were Middle Eastern migrants. And even in southern Africa, thousands of miles away, the people get about 5% of their genes from backflow migrants. In fact, the Khoe-San of southern Africa get some of their pale skin genes — an advantage in sun-poor lands far from the equator — from these Eurasians. Continue reading “The Backflow into Africa”