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Evolution of Hair

While some of us define ourselves by our faces and bodies, others place a lot of weight on how our hair looks. After all, hair (on your scalp, face and body) is our body’s fashion statement. You’re born with a natural hair color, shape and hairstyle.

Then, we get old enough to realize we have the power to control how good (or bad) our hair looks. We decide how long or short it is, or how black or blonde (or blue) it is. You can show people how sexy (or potentially wacky) you are with a few simple snips. People become inspirations (thank you, Ms. Aniston), or the proud butt of jokes (Mr. Trump).

Hair used to be a whole lot more purposeful than body ornamentation. Sure, we realize that it protects us from the sun. Our eyelashes act as defense against bugs, dust and other foreign particles. But back in the day, the hair covering our nether regions camouflaged our reproductive parts from threats. By lining our armpits and groins, our dry hair actually lubricates our arms and legs, so we can move about without chafing.

For early humans, hair kept them warm, provided camouflage, protected them from cuts and even served as a nice handhold for the young. We lost a lot of hair because of the invention of heaters and parkas. Our ancestors most likely started hunting in hot, tropical areas.

QUIZ: How Healthy is Your Hair?

Bare skin adds to our internal cooling system’s efficiency. So why’d we keep the tuft at the top? It may have to do with a little mating ritual. Males with the most impressive hair frightened away rivals, got the girl and fathered some kiddies. Hence, head hair may have played a big role in obtaining a partner and producing the next generation.

Hair on your face grows as you age. The hair on and in your ears protects you from insects that might find your ear canal interesting. You recruit dormant follicles so you can grow more hair to keep warm in the winter.

As far as your nose hairs, beware of pulling them out. This can lead to infections from traumatized hair follicles. Infections in the area from the bridge of the nose to the corner of the mouth can drain into the brain and cause a clot in the cavernous sinus. You can use a specialized nose-hair clipper that acts as a weed whacker for your nostrils.

You may have noticed that pubic hair is quite different from head hair. Given that pubic hair has a short growth period, it never gets a chance to grow longer, less curly and less coarse. Within six months, these hair follicles die and the hair falls out.

Pubic hair has a few purposes we know of. It acts as a buffer to reduce chafing and helps to hide the genitals. Pubic hair also provides a large surface area to disperse sweat. Many animals attract potential partners with the odor of sweat from the groin and underarms. While today, these odors most likely keep people on the other side of the elevator.

In the past and present, hair helps protect against malaria. Our hair signals the presence of the Anopheles mosquito before it bites. (Kids are at greater risk for malaria because they have less hair on their legs.) The most likely purpose of our hair was probably to serve as an early warning of bodily threats. Today—with the advent of the bikini wax and laser hair removal—we often ignore the armor function of hair.

MORE: Want to Try Laser Hair Removal?

Aside from these utilitarian functions, hair reflects a lot about our self-esteem, gender, taste, age and attitude. It plays a big role in determining how people are attracted to us, and whom we’re attracted to.

It can even be a source of conflict. Women sometimes prefer shorter hair, especially as they age. Men report being attracted to longer locks. On a more important note, hair shows us much about our health status. Hair growth and hair loss can signal mishaps inside our bodies. We care about our hair. It’s no surprise that people in the United States alone spend $50 billion on hair care.

We care about cleaning it, beautifying it and keeping it in some places (while removing it from others). Like skin, your hair can also glow and shine. You just have to use the right solutions for you, to keep your hair at its best.