Forget English or Spanish or Mandarin.

Lots of people haven't even heard

what might be the most important language in human history,

Proto-Indo-European.

Its last native speaker probably died thousands of years ago before it could ever be captured by any system of writing, which

would seem to make studying it just slightly less challenging than describing the details

of an ice sculpture based on a puddle of water. From KERA in Dallas, this is think. I'm Chris Boyd.

The thing is, there are clues.

We know this early language arose somewhere between Europe and Asia

and spawned hundreds of linguistic descendants that are still with us today,

from Hindi to Russian to Portuguese.

And scholars looking to trace those evolutions are finding ways to apply new science, like DNA

sequencing, to reconstruct this language that only seems to have vanished.

My guest, science writer Laura Spinney, covers all of this in her new book, Proto,

how one ancient language went global.

Laura, welcome to think.

Thank you. It's a pleasure to be here.

You write that the Big Bang of the Indo-European languages is easily the most important event

of the last five millennia in the old world. That is such a wonderfully bold claim.

So tell us a little bit about how you arrived at it.

Well, because those languages, the Indo-European languages of which there are about 400 living today,

are now spoken by nearly half of humanity.

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