When Valleys Whistle Back The World's Whistled Languages

A whistle, in open country with the right shape of land around it, can carry as far as eight kilometers, or about five miles. A spoken shout gives up long before that. Yet there are people for whom a whistle is more than a signal that says "come here" or "danger." It holds a whole sentence: who is speaking, what they want, whether the sheep got through the gate, and whether anyone is coming to dinner.

On the Canary island of La Gomera, in the mountains of northeastern Turkey, and in the highlands of southern Mexico, people have used pitch and breath to carry ordinary conversation across canyons. The linguist Julien Meyer has spent years documenting these traditions, and he has found whistled languages in many corners of the globe. Almost all of them started in the same kind of place: remote mountain villages and dense forests, where the land itself got in the way of talking.

This episode is about how that works. How does a whistle encode a language? What happens inside the head of someone listening to one? And why, after what may be centuries of use, are these traditions going quiet, even as a few determined efforts try to coax them back?