Body Hair . What's it for?

I'll take a stab - what the heck

70% of body heat is radiated out your head, so colder climates would need a "cap"

Armpit and groin hair would be essential for pheromone distribution.

As for other surface hair I cannot guess

GA, But where's Del the Cat? We could ask him what his wiskers are for. Or those hairy little things that bugs wave about. I suspect body hair also works as a proximity detector and vibrational interface, warning us like radar.

C.P.

Shouldn't you know what whiskers are for? I mean, going by your avatar, aren't you a cat yourself?

I think Edignan hit the nail on the head with body heat. Your head is giving off heat -statistic noted. The armpits and groin are also hotter than other parts of the body. Is hair an expression of heat?

This leads me to the bizarre conjecture: do men have more facial heat than women?

You guys are intuitively quite close Artsmith and Edignan.

On the head it does serve as insulation in cold, but also to cool in hot temperatures. Body hair increases surface area, promoting evaporation and thus cooling. In those "sensitive" areas, It improves sensitivity to touch as well. It also serves as a secondary sexual characteristic, which I'll let everyone google...

milo

ditto, ditto, and ditto

HOWEVER that doesn't explain why hair now grows from my ears ... maybe as we get OLDER we haven't the energy to swat the bugs as readily.

AND, do bald men NOT need this 'top' insulation?

AND, why do some men have backs hairier than some gorilla do, and others are as smooth as ... well ... as a baby's bottom?

AHHH, the mysteries of the world ... ain't it great

That is easy the hair out of the nose and ears are as compensation
for the hair-loss on top.

But with waste disposal, why don't we have shiny bottoms like baboons, it makes sanitizing a lot easier

they say it all started with garden of eden. We lost our overall hairiness, amen. And were cast out of the tribe. Something to do with a fruit we weren't supposed to eat. But snakes ate it and they seemed to be ok. No legs of course, but hey the substitute is functional, movement a new scene.... voila the "hairless" apes.

Fur would be nce, a lovely soft fur alll over.

" ... Fur would be nce, a lovely soft fur alll over. ... "

Are you SURE?!?!?!?!?

what body hair?

this lady would be great to hug!

Can you imagine the static build up from friction on a very dry day....... owee!!

there's a good discussion on this here.

but still, the puzzle remains. it's so hot here in the Middle East, yet the natives are soooo hairy.

it gets so cold in China and Tibet, and they're soooo hairless.

please see my post 3 above. The hair is not for warmth, its for cooling wicking away perspiration thus heat.

milo

I believe that hair in the groin area and under the arms improves ventilation in those areas (air gets trapped between the hairs; the movement of the limbs causes air to be "pumped" in and out of between the hairs).

It gets quite sticky when I shave my armpits. A nice compromise is to trim instead of removing the hair by shaving. So I can wear a vest without looking all caveman-ish.

That assumption works provided that you are running down the halls at work in the BUFF.

hmm i learnt some stuff about that in biology quite a while ago...

when you feel cold your 'pores' raise or what people call goosebumbs

the hairs basically stand up trapping some of the heat released from the body so that the body temperature would hopefully normalize...

The volume of hair and different locations i can't readily answer... but i guess the previous answers could answer the rest of stuff :)

And as for nose and ear hair compensating for shiney tops, I've still got (less) plenty of hair on top, but the orifice grooming has had to go way up in recent years.

There is a bit about hair in this thread.

http://cr4.globalspec.com/thread/2537#newcomments

I never received a satisfactory answer though.

"protection from the elements and tree branches."

Please explaaiin

The reactions of CR4 participants to this question made me stay with this mob and I haven't looked back since. We all knew more about hair in the end and that was what we were after.

Hope it helps, Ky.

Simply observation that when I have short hair on the head I am more likely to be hurt worse when I nudge a shelf or branch than when I have longer hair (or a hat ). Simly, the sun is more irritating when hairless or hatless.

It doesn't have to be for anything. Asians etc seem to do quite well without it. Although it seems reasonable that in the past head hair had some benefit as all humans have it (at least when young).

Unless there is something about body hair that helps or hinders survival there wont be any "selection pressure" to select for or against it. Hence it and other useless bits (ear lobes, freckles) just hang around.

The hairy female tennis players may be a result of better athletes having higher testosterone levels, or of tennis currently being popular in countries when women are naturally hairy, or even of non shaving/bleaching being fashionable at the moment.

The late Steven Jay Gould wrote a number of articles on this topic, explaining how just because an animal has some feature doesn't mean it evolved it for a reason.

It's not like we were "designed". (adding cat to pigeons)

Why do humans have hair?

1. So that people can write musicals about it.

2. So companies can make shampoos, dyes, clippers, combs, brushes, razors, and don't forget shaving cream!

I remember what a preacher said on TV, that GOD made everything for a reason..yes even body hairs..

He explain that our eyebrows are there to prevent sweat from our foreheads to go directly into our eyes.

Noticed how we walked? There is a friction occuring on our armpits...the hair helps to lessen it and therefore preventing "Blisters under your armpits"

Filters for our noses and ears..

And GOD made TV so preachers could collect more money. Money that you earn by the sweat of your brow.

Hi,

some facts and speculations:

body hair is still in our genes but these are switched off - so this must be a result from our evolution. (There are some people with more or less complete fur.)

Above explanations are not convincing except for pheromones in remaining areas of sexual interest. As these are not existing in our nearest relatives this was a consequence of our evolution.

There is only the theory of the "water-ape" living on the shores of big lakes in the African rift valley that may explain this.

If our ancestors have been very often in shallow water then a better protection of pheromone producing regions is needed to prevent early washing away the attracting odors.

This too is giving an explanation about length of hair: on our head much longer than needed for protection from sun-rays, so likely to grasp for the youngsters at swimming. Babies will cling their arms around the neck of mother or father if these are swimming or diving, 2 to 5 year olds will grasp the hair to secure.

This was first postulated by Elaine Morgan - search for her books, its fascinating.

Loss of body hair is a benefit if you have to run for long distances in warm climates. Same situation as above: the shores of lakes (much bigger than most may imagine, look at the size of Victoria-lake today) have been crowded by wild big cats preying for early humans at the time our ancestors transformed from mostly 4-legged to 2-legged walking. So how to survive: flee as fast as possible into the shallow water and remain there for most of the day and some hours oft the night? And forage along the shore of these lakes for best-known food: crabs, mussels, snails: full of omega3 fatty acids essentially needed for brain development.

See the book from Steven Cunnane: Survival of the fattest.

So this environment shaped our loss of fur and remaining and changed hair.

Clothing for protection was invented much later.

Baldness in aging man is a result of changing testosterone to dihydro-testosterone levels but still not completely clear in biochemical actions. This was cleared by the blocking of conversion of testosterone to dihydro-testosterone in patients with benign or malignant prostate growth.

This baldness is often developing in an age that was not often reached by our early ancestors. So this is likely not an adaption to environment.

RHABE