You're listening to, you're listening to, you're listening to Radio Lab.

I just thought I'd see if I can get the sound of baby sleeping. This is Radio Lab. Today's program is about sleep.

I don't have to tell you how good sleep is. You do it yourself every night, or you try.

And how wonderful when it actually works, when you can close your eyes and forget the day

and just drift off into oblivion, like a little baby.

But let's suppose that you are a little baby, this little baby, and you grow up to become a

scientist, like one of the scientists we'll hear from in little baby, and you grew up to become a scientist,

like one of the scientists we'll hear from in this program, and you decide to ask what should be the dumbest question ever. Why do we sleep? And not just us. Well, pretty much everything sleep.

As far as we know, all mammals do it. All birds. Bees, locusts, cockroaches, crayfish, reptiles, insects, scorpions.

Everything that's been studied has something that looks like, sleep.

It's a mystery.

Most things we sort of know what they are for and also how they work.

But sleep is really in your face.

I mean, everybody does it.

You do it from the cradle to the grave.

You can't help doing it because if you try to stay awake,

you know, at some point it's irrepressible.

And we don't know why?

That's a shameful state of affairs.

How can you be a scientist in the 21st century and not know the answer to that? There you go. Okay. At least for shame, okay, it is not for true. That's a pretty good way to begin, no. With shame? Yeah, yeah. Today on Radio Lab, we're going to try to correct this shameful state of affairs when it comes to the subject of sleep. We'll talk with people who can help us understand what it's for.

Why we do it.

And what happens when we don't?

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