Why do lice want to live in your hair?

If head lice were acrobats, your hair would be their tightropes. Their tarsal claws and spines, located on each of its legs, are specially adapted to cling to human hair and their eggs are glued to hair strands near your warm scalp. When another set of tightropes get close, in the form of another person’s head, they migrate by simply crawling from one strand to the next.

Why do lice want to live in your hair? These growing insects feed on human blood. Without it “they starve and die within 15 to 24 hours.” The warmth of our scalps helps their eggs hatch, too. Learn How Lice Turn Your Hair Into Their Jungle Gym with this Deep Look. The video also shows other types of specially-adapted lice species.

So how do you get rid of Pediculus humanus capitis if they’re so specially adapted to human heads? From the video:

Researchers found in 2016 that lice in the U.S. have become resistant to over-the-counter insecticide shampoos, which contain natural insecticides called pyrethrins, and their synthetic version, known as pyrethroids.

Other products do still work against lice, though. Prescription treatments that contain the insecticides ivermectin and spinosad are effective, said entomologist John Clark, of the University of Massachusetts, Amherst. They’re prescribed to kill both lice and their eggs. Clark said treatments such as suffocants, which block the lice’s breathing holes, and hot-air devices that dry them up, also work. He added that tea tree oil works both as a repellent and a “pretty good” insecticide. Combing lice and eggs out with a special metal comb is also a recommended treatment.

Next: What makes a tick stick? Plus: More videos from Deep Look.