If you’re squeamish, you might want to skip this one…but those little creatures are still going to be on your face.

As you read this, there are likely tiny, eight-legged mites called demodex going about their daily business on your face. Scientists have identified 65 different species of them in all, of which two—Demodex folliculorum and Demodex brevis—hang out on humans. They especially like hair follicles and are commonly found where hair grows on or near the face. Have you got a beard? There’s probably quite a few mites in there. What about nose hair, eyebrows, and eyelashes? Ditto.

The semi-transparent and relatively harmless creatures, which are also sometimes referred to as eyelash mites, are very small, which is why you don’t spend much of your day trying to squish them with Kleenex. The average male is only about 0.4 millimeters long. Instead of catching bugs like spiders, the mites prefer to dine on skin cells and facial oils. They prefer the face because it has the oiliest areas on the human body. They also like to lay their eggs in hair follicles or glands, which hatch after three or four days. The average lifespan of one of these little guys is just a few weeks. Around 33 percent of children carry these mites. It jumps to 50 percent for adults, and two-thirds for the elderly.

Here’s where things really start getting a bit freaky. Some scientists theorize that the mites could be the root cause of rosacea, the condition that causes many fair skinned people to appear like they’re permanently blushing. A 2012 review conducted by the National University of Ireland contends that bacteria that reside in the bugs can trigger the condition. Others think that the mites could be the culprits responsible for a few other skin disorders.