David Reich is a geneticist at Harvard whose lab helped pioneer the field of ancient DNA — extracting and sequencing genetic material from human remains thousands of years old. What they found overturned nearly everything scientists thought they knew about where we come from.
Before 2010, the story of human migration was mostly guesswork. Since then, ancient DNA has revealed that modern humans interbred with Neanderthals, that a group of steppe nomads reshaped the entire ancestry of Europe, and that in some places the population was replaced so completely that the people living there today share almost no DNA with those who lived there just a few thousand years ago.
This video We’ve been guessing about ancestral history — until now is featured on Big Think.