*Ø* C'mon people now, smile on your brother! Ev'rybody get together,
try to love one another right now.


Human populations are tightly interwoven
By Michael Hopkin
Nature

Family tree shows our common ancestor
lived just 3,500 years ago.

The person from whom everyone today is descended may have lived around 1,500 BC.

The most recent common ancestor of all humanity lived just a few thousand years ago, according to a computer model of our family tree. Researchers have calculated that the mystery person, from whom everyone alive today is directly descended, probably lived around 1,500 BC in eastern Asia.

Douglas Rohde of the Massachusetts Institute of Technology in Cambridge and his colleagues devised the computer program to simulate the migration and breeding of humans across the world. By estimating how different groups intermingle, the researchers built up a picture of how tightly the world's ancestral lines are linked.

The figure of 1,500 BC might sound surprisingly recent. But think how wide your own family tree would be if you extended it back that far. Lurking somewhere in your many hundreds of ancestors at that date is likely to be somebody who crops up in the corresponding family tree for anyone alive in 2004.

In fact, if it were not for the fact that oceans helped to keep populations apart, the human race would have mingled even more freely, the researchers argue. "The most recent common ancestor for a randomly mating population would have lived in the very recent past," they write in this week's Nature.

CONTINUE

[No wonder we can't get along--we're all relatives! -v]

[Emphasis added. -v]