Face mites live on nearly everyone — studies suggest practically every adult on the planet has thousands of them.

These microscopic bugs suck oil and cell material from your pores, and lay eggs in your hair follicles.

Typically, they're harmless and unnoticeable, but in extreme cases, they've been associated with a skin disorder called rosacea.

Following is a transcript of the video.

There's a creature scurrying across your face. Right now. Yes, you.

And at some point, maybe now, maybe in a few days, it's going to find a nice cozy pore in your skin, and lay a single, enormous egg.

Meet the face mites.

They're smaller than a grain of sand, are a kind of arachnid, like spiders, and they feast on the oil and cells in your skin. Particularly on your oily nose, cheeks, and forehead.

Scientists suspect they've been living on us since the dawn of humanity over 200,000 years ago. And today, studies suggest practically every adult on the planet has thousands of them. Odds are you've been living with them your whole life. Babies quickly get them from their parents a few days after birth.

And once those face mites are on you, the only thing they enjoy as much as slurping oil and nutrients from your pores is having sex. All over your face. Afterwards, females burrow deep into your pores where they lay their eggs.

The eggs end up in one of two places depending on the species of face mite. The first species, called Demodex folliculorum, lays its eggs in your hair follicle. While the second prefers nesting in your sebaceous glands. And in under two weeks, the babies hatch, mate, lay their own eggs, and die, leaving behind a pile of decomposing corpses.

Now, you can wash some of this off. But you'll never eradicate them completely. Because even if you treat them with antibiotics, they'll return in about 6 weeks, tops. You'll pick them up from towels, pillows, and your loved ones.

Well, that all sounds horrific.

But usually, face mites are harmless. They only become a problem when they multiply out of control. This can happen in people with an impaired immune system. It's also been seen in people with a painful skin condition called rosacea.

Normally, you'll have around 1 or 2 mites per square centimeter of skin. But one study found that people with rosacea had 10 times the normal amount.

Now, believe it or not, in some cases, face mites can be useful. Researchers can actually study your face mites to learn about your ancestors. You see, most mites often stay within a community. So over time, they've evolved into distinct lineages in different geographic regions. And by comparing their DNA, scientists can trace how different groups of humans migrated across the world. For example, a study found that European mites genetically diverged from East Asian mites about 40,000 years ago. That's the same time European and East Asian humans parted ways.

Pretty handy.

So when it comes down to bugs crawling on you, it could be a lot worse.