America's favorite fruit is in big trouble.

Consumers have an expectation for how bananas look and taste, right?

And farmers are accustomed to growing this variety.

It's Thursday, April 26th, and it's also Science Friday.

I'm Scifry producer Kathleen Davis.

Even though there is just about a thousand

different types of bananas, American consumers are used to eating just one.

The Cavendish. There's bad news though. A fungal disease is putting them at risk of extinction.

We'll talk about that story in just a little bit, but first let's find out what bird dreams sound like. Yep, you heard that right. Here's guest host Maggie Kurt.

Bird sleep perchance to dream, But what about? We've got more insight into this now thanks to

researchers from the University of Buenos Aires. Turns out the sirenx, a bird's voice box, silently moves as it slumbers, kind of like the way

your sleeping dog might move its paws to run.

And these scientists have figured out a way to translate that movement into song. We can now

effectively listen to birds talk in their sleep and that gives us some clues

about what's going on in their heads. This is all published in an amazingly

titled journal called Chaos and joining me now to talk more about his fascinating

work is my guest Dr. Gabriel Mindlin,

professor of physics at the University of Buenos Aires in Buenos Aires, Argentina.

So animals sleep, animals dream, or at least they have brain activity that would mean dreaming if we saw it in humans and that includes birds.

Your team found that birds are moving the sirens in their sleep.

So tell me how you found this and what you saw.

We have been studying the physics of birds on for many years and the framework of those studies

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