While Homo Sapiens were evolving in Africa the Neanderthals and closely related Denisovans were evolving in Europe and Asia. It now appears that modern humans began interbreeding with these groups around 100,000 years ago before they went extinct around 40,000 years ago. Sub-Saharan Africans never came in contact with these groups but the rest of modern humans have between 1-4% of their genome which came from Neanderthals and Denisovans.

(Magazine – Archaeology July/August 2016)