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This is Scientific American 60-second science. I'm Christopher Ndallata. Got a minute?

Modern European languages tend to share their names with the places they're spoken.

Swedish, Sweden, German, Germany, and so on. But where did they come from before that?

Well, one theory is the Anatolian hypothesis, Anatolia referring roughly to the Asian part of Turkey.

So the proposal was that it was agriculturalists from the Near East and present-day Turkey and Cyprus

who were bringing agriculture to Europe, and that this mass movement of people bringing agriculture

also brought languages.

David Reich, a geneticist at Harvard Medical School.

The Anatolian hypothesis has languages from the Indo-European family hitting Europe around 8,500

years ago.

But as with any academic theory, there's a competing idea, the so-called step hypothesis,

which says it was herders, not farmers, who galloped in from the

grasslands of Central Asia five or six thousand years ago, bringing language with them. But the

step hypothesis was lacking for evidence. Now Reich and his colleagues have analyzed the DNA found

in the remains of 94 ancient Europeans. And this molecular evidence does indeed

point to a migration from the steppe into central Europe about 4,500 years ago.

And it's a massive event. At least three quarters of the population got replaced by people

...