This is Science Friday. I'm Ira Flato coming to you from the Sydney Goldstein Theater in San Francisco.

One of my favorite topics to discuss on Science Friday is the microbiome, you know, that vast

menagerie of trillions of microscopic bacteria and fungi that live on us and inside of us.

But I found out recently there's a lot more living on us than just microbes.

Take, for example, the face mite.

Yes, you heard me correctly.

It's a tiny arachnid that lives on your face.

And in some studies, it's been found in 100% of people sampled.

So, chances are yes, they're hiding out in your oil glands and hair follicles right now.

I see a few of you squirming in the seats about that.

Yeah, I understand it.

And you know, if you do the math,

there are about 5 million hair follicles on your body, and there are more than 7 billion people

on Earth. So there are lots of face bites everywhere you look. And joining me now to talk about

these ubiquitous creatures is Michelle Troutwein,

curator of entomology at the California Academy of Sciences here in San Francisco. Welcome to Science Friday.

Thank you. Thank you.

Okay. What exactly is a face mite then?

So a facemite is an arachnid, so it's related to a spider.

They're microscopic, and they kind of look like a stubby little worm with eight little legs at the tip.

And it's safe to assume that everybody in our audience might have one at least?

At least one.

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