When clumps of hair begin to fall out, people often feel that they're nearing the end of the world. This is because society places such a premium on hair. Hair is associated with health, success and agreeability. In some cases, people who are balding are viewed as frail or weak, simply because their hair wasn't as thick as before. Aside from being the stuff that rests on our head, the main function of hair is to provide protection. What kind of protection, you may ask? Well, read on.

Keeping Your Head Safe

Like an organic helmet, the human hair is surprisingly a good barrier against the natural elements. Since the head is the closest to the radiation of the sun, and experiences most of the bumps and falls of childhood to early teenage years (and even well into adulthood), it requires no less than the most efficient means of protecting its immediate surface.

The protective function of the human hair is to prevent germs, insects and other undesirable creatures from directly invading the scalp. The thousands of strands of hair act as shields; the 'invaders' stick to the strands, where you can wash them off with shampoo or similar hair care products.

Temperature

There is evidence that one of the main channels of temperature change in the body is the head itself. That's why people wear bonnets and similar articles of clothing during winter, because the heat escapes easily through the head. With a full head of hair, the process of heat escape is retarded, or gradually slowed down.

Now, how does the hair help in cooling you down when the summer months come? If we are to backtrack a bit to the protective function of the hair, then we'll immediately see that the hair actually acts like a roof over the head.

The melanin present in the hair helps block out the heat of the sun (direct radiation). This works in conjunction with the sweat and oil glands in the human scalp. They simultaneously work to keep the scalp moist, but at the same time cool from the evaporation of sweat.

Other Interesting Uses

Aside from literally housing your head from the sun and the rain, hair has some other interesting uses as well. You should remember that hair exists not only in the general scalp area, but also on the arms, legs, chest and back. What's the purpose of these tiny hairs, and why do we have them?

A few lessons from old Darwin should teach us something. All mammals are warm blooded, and therefore require at least some means of stabilizing temperature. Since humans have adapted to variable climate conditions, the hairs on our body have decreased both in thickness and in number.

If we increase the thickness of our body hairs, we'll end up looking like orangutans and gorillas; that's how close we are genetically to these gentle apes.

Anyway, back to the hair. The nerve endings of hair follicles are quite specialized: you feel when a bug is crawling on your arm (and the hairs detect this, so you can swat the bug promptly). But at the same time, when a person runs his or her hand rhythmically against your scalp, you feel relaxed.

Is this a contradiction? Not really. The nerve endings of hair follicles have been biologically designed to recognize different sensory input; therefore, it can differentiate between a painful tug on the mane and a soothing massage.