There has been an amazing discovery made studying the DNA of the remains of a Neandertal, dated 38,000 to 44,000 years ago. Scientists found that many of us have Neandertal ancestors. They inter-bred with our ancestors until about 400,000 years ago before their lineage separated from us. This inter-breeding occurred in the Middle-East but not in Africa. This means that human beings with ancestors that originated from the Middle-East (almost the rest of the world) have more neandertal genes in them than descendants of the Africans who refused to migrate and instead, chose to stay in the African continent. (
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