Hey podcast listeners, this episode has lots of jokes.

Some people might find the jokes offensive.

In fact, the thin line between being funny and being offensive is our theme today.

If you're listening with the young kids, you might want to save this for later.

I say a lot of absurd over-the-top things.

Because if people see a train wreck possibly coming,

they're going to listen.

Welcome to Hidden Brain, I'm Shankar Vedantam.

On today's episode, I'm going to give you a special technique to pure into someone else's head.

It's using humor, the joke. What we laugh at, and what we don't laugh at,

tell us very important things about ourselves and about other people.

We got people lab coats examining dick jokes.

Comedian Billburys here to help us explore why we laugh at jokes that push the boundaries,

NPR's Elizabeth Blair join me for that conversation. It's coming up soon.

But first, I want to tell you about some research into what makes people laugh.

This is Robert Lynch. He's an evolutionary anthropologist.

He studies how traits pass down through evolution affect human behavior.

He now works at the University of Missouri.

Instead of asking, do you prefer blacks or do you prefer whites?

Or do you associate women more with career?

And men more with family or the reverse?

You actually time them on how fast they categorize things than a keyboard.

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