From Wisconsin Public Radio and PRI, Public Radio International, it's to the best of our knowledge.

I'm Anne Strange Champs.

Thanks so much for being here, everybody.

So how many of you remember the first time you fell in love?

I do.

He was tall, dark, handsome, seriously ripped. A little

uncommunicative, maybe on the mysterious side. His name was Batman. I'm not kidding,

really. Batman was my first crush.

I was five, six years old, and I used to watch them on TV every week.

But you know, first crushes wear off infatuations kind of go away.

I moved on to somebody much, much hotter.

Catwoman.

How do you explain the crazy randomness of who we fall for?

You know, why is it that some crushes burn out while others grow into shared romance and lasting intimacy? Well, today we're going to see if science, and in particular evolution,

can help unravel one of the greatest mysteries in the world.

Love.

So where should we begin?

How about sex?

Our first guest today is a biologist who has devoted her life to laying bare the mysteries

of sex in the animal kingdom.

Her name is Dr. Karen Bandar.

You have maybe seen her on her web series, Wild Sex, or caught her on Discovery World, National Geographic, the Science Channel.

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