At Slate, Steve Olson tells us Go back a few millenniums, and we’ve all got the same ancestors.
It gets even stranger. Say you go back 120 generations, to about the year 1000 B.C. According to the results presented in our Nature paper, your ancestors then included everyone in the world who has descendants living today. And if you compared a list of your ancestors with a list of anyone else’s ancestors, the names on the two lists would be identical.
This is a very bizarre result (the math behind it is solid, though—here’s a brief, semitechnical explanation of our findings). It means that you and I are descended from all of the Africans, Australians, Native Americans, and Europeans who were alive three millenniums ago and still have descendants living today. That’s also why so many people living today could be descended from Jesus. If Jesus had children (a big if, of course) and if those children had children so that Jesus’ lineage survived, then Jesus is today the ancestor of almost everyone living on Earth. True, Jesus lived two rather than three millenniums ago, but a person’s descendants spread quickly from well-connected parts of the world like the Middle East.