David Reich

But we now have data not yet published from the Netherlands, which is clearly the same population of Beaker people that's spreading in Britain.

And there it's very disruptive.

And you actually have the whole series of people before and after.

You see that earlier Corded Ware people are local, which is actually very unusual for Corded Ware.

They're actually local people adopting the religion of the Corded Ware, but mostly local ancestry.

And then the Beaker arrival is incredible disruption.

There's almost no continuity, very little continuity.

So probably what's happening with the Beaker individuals is one way or the other, you have some kind of people who expand demographically

and displaced people somehow, rapidly displaced people over a period of well less than a century.

So we don't know.

And I think there's debates even about that.

I think one example I've heard archaeologists I work with think about is...

is the Comanche in the US Southwest, where it's another horse-based expanding group.

They expand super dramatically in parallel to the Spanish expansion and alongside the US expansion before encountering the US, militarized United States at some point.

It's local.

There's local bands of people expanding.

They go on campaigns.

They expand to certain areas.

The Beaker people and the Corded Ware people, they're contemporary to ancient Sumer and to a lot of the...

Egyptians that we actually have written history from.