- from Skin
When most people hear the word “hair,” we think of the stuff on our heads. But those fibers make up only about 100,000 of the 5 million or so of our total hairs. In fact, each of us has about the same number of hairs as an ape!
Hair is often used as a decoration, but it serves a more serious purpose. It cushions minor blows, keeps the sun off, and keeps us warm. It can alert us to a touch or a change in temperature. And eyebrows, eyelashes, and nose hairs help keep dirt and foreign objects out of places where they shouldn’t be.
Fingernails are survival tools as well—and not just for the one-third of Americans who bite them. Try picking up a pin or a coin off the floor without using fingernails. Even better, try to scratch that itch on your scalp.