Hair

Hair is strange stuff.  Biologically it is a filamentous bio material, composed of proteins, notably Keratin.  All mammals have it, although the amount can vary according to the stage of life of the mammal in question.

 

Male Pattern Baldness

I don't have much hair left on top of my head.  I have typical "male-pattern baldness". I used to have a thick head of hair in my teens and early twenties, going grey at the sides (premature white hair is a recognised trait in my family) until I caught a scalp fungal infection during an extend deployment exercise when I was in the Army.  The constant heat,sweat and dirt under the obligatory headgear during a very hot and sunny week in the field left me with chunks of hair and scalp peeling off.  Think of athletes foot, but covering your whole scalp.  Eventually I got the fungus cleared up, but my thick hair was now thinned out, and I soon joined the ranks of balding males in my thirties.

But why hair? What biological function does it perform?

It's primary function appears to be insulation.  In cold weather, the hairs of the body, especially the arms extend, trapping a layer of air, which acts as an insulator.  The hair on the head also stops heat loss.  The head is extraordinarily well supplied with blood, needed to maintain the oxygenation of all of the sensory organs and the brain, and this also means that it is a major area of heat transfer, hence the good insulation by hair. (Until you go bald, then a hat becomes less of a fashion statement, and becomes more of an essential survival tool in the winter).








Scary Hairy

But why hair in the armpits?
We definitely don't need insulation there, it's well protected by muscle on all sides, and this area normally gets too hot anyway, so why hair.
Possibly for its wicking effect, drawing out excess perspiration, allowing for evaporation and hence cooling.
(As an aside, I really don't understand why the French insist that ladies' armpits should be positive bundles of hirsute overgrowth. )

But why pubic hair?
Insulation? no, not really.  This area is pretty well kept warm by normal blood supply, and an area which is pretty well protected by clothes (I know clothing is a relatively new idea, speaking in evolutionary terms and times, but even over 20,000 years we should have seen some reduction)
Wicking effect, like the armpits?  Don't think so, sweat does not seem to accumulate down there.

Protection?  Hair can have a padding effect.  Nowadays if I'm working in enclosed spaces, doing some DIY, I have to make sure I'm wearing a hat of some kind.  Little bumps can cause major skin tearing without a nice thick layer of hair between my scalp and a wooden beam.

Sexual References past this point.  Caution.

But why Pubic hair?  I certainly don't thrust this area at wooden beams, or any sort of object really. 



The only time this area gets a pounding so to speak, is during sex.  But even the most violent consensual sex shouldn't be so violent as to cause bruising, so does this area really need that protection against impact?

So what is pubic hair really for?
Is it camouflage?  to disguise the areas which make us embarrassed?
Display, to call attention to areas we want displayed and noticed?
Fashion? So we can make pretty and silly shapes?

Nope.  I don't think it's any of these.  I think it's been left for a reason.

Let's compare a human to a chimpanzee.  We share about 96% of a common genome, so it could be argued that humans are actually mutated chimps.  Chimps are also covered in hair, but to a much greater extent. We both have hair on the back of our hands, our arms, legs, head and body.

Humans have lost most of our hair compared to a chimp, possibly as we now need less hair for insulation due to our ability to make and wear clothing.

So why is pubic hair left. It does not fulfill any physical need for protection, insulation or any other.

I believe it's for embarrassment.

Humans have this innate need to fell embarrassed when pubic hair is on display, it makes us feel ridiculous.  When we share this embarrassment and feelings of guilt and inadequacy with our chosen partner, it binds us closer together, makes for lasting relationships.

So we need pubic hair for love, for a closer and moral binding with a chosen partner.

It also has a secondary purpose in reminding us of our ageing.

If you spot a white pubic hair, it is the first sign of old age.  So it reminds us of our mortality.

Speaking of advancing years, why on Earth does hair grow more profusely out of our nostrils and ears. 
Do our ears need more insulation as we get older?  Do our noses get more prone to frostbite?
I don't think so, it's just another signal to our possible sexual partners that we're completely past it, ugly and to find someone else.

I used to laugh at those adverts for nose and ear hair trimmers.  No longer.

I wish I had more hair where I wanted it, not ears or nose, but head.

Finally, one of my favourite pieces from the 70s is from the musical Hair.

Frank Mills is a great piece of music, with unusual phrasing, which changes an almost country and western tune into something else.