From the brains behind brains on, this is the moment of um

answering those questions that make you go. The moment of um comes to you from APM studios. I'm Mark Sanchez.

Have you ever been to a petting zoo? That's a special area in the zoo where you can actually touch the animals.

Sorry, no lions or tigers in the petting zoo.

But there are usually farm animals like pigs, donkeys,

maybe some chickens, and probably some goats.

I think the goats are the most fun.

Their wool is really soft touch and they love to climb on taller things like tree stumps or even other animals to get a better view.

If you've ever looked closely at a goat, you might have noticed

that their eyes are pretty unusual. One of our listeners noticed too, and wanted to know more.

Hi, my name is Emma.

I'm from Reading, Connecticut, and I wonder why goats pupils look like thin lines instead of

circular balls, like other mammals and animals. So with a horizontal pupil that allows the goat to see more widely in front of them, to the of them and behind them along the ground.

And that's useful because that's where an animal that might be hunting them

would be likely to come from.

Hi, I'm Martin Banks, I'm a professor of optometry and vision science at UC Berkeley. The horizontal pupil, like a line, is actually pretty common among mammals.

Particularly common among mammals that are herbivorous, that is that they live on the ground and they eat plants, cow, sheep, goats,

horses, all have the horizontal line pupil.

It's predators, mammalian predators that tend to have circular pupils

or vertical line pupils.

There are other pupils that we just find kind of interesting

and bizarre in the animal kingdom.

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