You're listening to Radio Lab.

I'm Chad Aboumrod. This is Radio Lab.

And I am Robert Quilwich.

And let's begin today with something deceptively familiar.

Fireflies are something that we have all loved as kids, right?

Catching them in the backyard, putting them in a jar and watching them glow.

So we don't tend to think of them as anything all that mysterious.

Well, they do one thing very

nicely, which is flash on and off. That's all fireflies do flash. But what interests Steve

Strogatz, a mathematician at Cornell University, is that there are places in the world.

Not here, but in Southeast Asia, in Malaysia or Thailand. Where fireflies don't just flash

randomly, like we're used to, they somehow flash together.

There are enormous congregations of fireflies along riverbanks.

How many?

It could be tens of thousands.

Tree after tree extending for literally miles along the rivers, all flashing in sync like a Christmas tree.

Rows and rows of Christmas trees all wired together going off.

And it's one of the most hypnotic and spell-binding spectacles in nature.

Because you have to keep in mind it is absolutely silent.

I mean, picture it.

There's a riverbank in Thailand in the remote part of the jungle.

You're in a canoe slipping down the river.

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