All non-Africans today trace their ancestry to a single population emerging from Africa between 50,000 and 80,000 years ago.
Adam Rifkin stashed this in Anthropology!
A Single Migration From Africa Populated the World ...
Modern humans evolved in Africa roughly 200,000 years ago.
But how did our species go on to populate the rest of the globe?
The question, one of the biggest in studies of human evolution, has intrigued scientists for decades. In a series of extraordinary genetic analyses published on Wednesday, researchers believe they have found an answer.
In the journal Nature, three separate teams of geneticists survey DNA collected from cultures around the globe, many for the first time, and conclude that all non-Africans today trace their ancestry to a single population emerging from Africa between 50,000 and 80,000 years ago.
The three teams sequenced the genomes of 787 people, obtaining highly detailed scans of each. The genomes were drawn from people in hundreds of indigenous populations: Basques, African pygmies, Mayans, Bedouins, Sherpas and Cree Indians, to name just a few.
The DNA of indigenous populations is essential to understanding human history, many geneticists believe. Yet until now scientists have sequenced entire genomes from very few people outside population centers like Europe and China.
The new data already are altering scientific understanding of what human DNA looks like, experts said, adding rich variations to our map of the genome.
Why leave Africa at all? Scientists have found some clues to that mystery, too.
In a fourth paper in Nature, researchers described a computer model of Earth’s recent climatic and ecological history. It shows that changing rainfall patterns periodically opened up corridors from Africa into Eurasia that humans may have followed in search of food.
Top Reddit comment:
Previous studies suggested that there were probably two different waves of modern humans getting out-of-Africa. These new 3 studies all confirm that no, there was only one main out-of-Africa event.
The erroneous inferences of previous studies were caused by the, previously unknown, Denisovan DNA found in Australian and Papuan aboriginals. This led the authors of previous studies to suggest that that "unknown" signal was due to a second out-of-Africa event.