Idea for evolutionary advantage of pubic hair

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I had an idea about why pubic hair develops. Most theories seem to involve pheromones or friction-reduction, which are almost certainly a factor, but those ideas fail to explain facial hair. Now, forgetting for a moment that women do not have facial hair (a big hole I only just realized), I'll put forward my idea: the genitals and head/face area are some of the most important parts of the body for survival and reproduction. It could be that the extra sensitivity provided by hairs (like the whiskers of a cat) give these areas advanced notice of potentially harmful stimuli. The tendency for males to be more aggressive might be a possible explanation for why this idea would be a factor for men and not women.

Any thoughts?

Sure. But the big evolutionary advantage is as an indicator of sexual maturity.

well disabuse yourself of that notion immediately. Women have facial hair. Just type it into google and see the thousands of products that have been developed for women to remove their facial hair and you will see what a fallacy to think women do not have facial hair is.

Hormonal activity for genders is on a spectrum, as well.

so that plugs up the hole in your theory.

Granted. The reason I've posted this, I guess, is to see if this idea hasn't been put forward before and if not, whether it seems to have any merit to other thinkers.

There seem to be fewer and fewer ideas left to be discovered. It's like any cool idea I seem to have has already been discussed in great detail. Like, I had this idea that maybe the expansion of space is caused by the densification of space within supermassive black holes, and I basically came across a similar idea online.

Actually, I did have what I believe to be one of the last original thoughts left about a week ago:

Richard Dawkins reciting Tenacious D lyrics. Seriously, go watch a video of his on YouTube to get his voice in your head. Now read this: "It's Tenacious D time, you Motherf***er go." I cracked up when I thought of that, so I feel relieved and proud to have now shared it with the world.

The problem with this idea is that human pubic hair, unlike cat whiskers, doesn't give any advance notice of anything. By the time pubic hair has contacted anything, the danger is already upon us. When it comes to sensing danger, our pubic hair is probably the last part of our bodies to find out about it.

In the most technical sense, the minute sensations induced in hair follicles occur a fraction of a second before the sensations produced by the same event on the skin. However, this is merely a pedantic and fairly trivial point, most likely.

Cat whiskers (even the shorter ones scattered throughout their body) generally reach out farther than your average pubic hair. This would seem to support the notion that any hairs under a certain length do not offer a large enough timing difference in sensation to afford practical evolutionary advantage.

In other words, Janissy: good point.

Pubic hair exists for the same reason men have nipples.

As a means of warding off predators in a butterfly-esque fashion?

No, men have nipples like women b/c all human fetuses at the very least (I don't know about other animals) start off female. I think males become male when the y-chromosome gene is triggered at some point during gestation. Also, I thought pubic, facial, head & other hair developed as a hygiene/heat conservation method. Also, body hairs are used to detect insects, bugs, etc. Eyelashes keep dirt out of our eyes * brows keep sweat out of the eyes. Would you want constant eye irritation due to sweat & dirt, to be cold constantly & not feel bugs so you'd be bitten constantly? It may seem weird but, be thankful for hair! Look it up if you want to double check.

Turn the question around. The ethologist Desmond Morris was among the first to refer to humans as "naked apes". So the question becomes not why do people have pubic hair, but why did homo sapiens evolve to have fewer and thinner hairs on most body parts.

I've read a number of interesting ideas on the subject, but there does not seem to be one generally accepted answer at this point in time.

Indeed. Humans, discounting hair loss, have hair on pretty much their whole bodies. I think the exceptions are the palms and soles.

When I wore a younger man's clothes I was told that pubic hair developed as a sign to others that we were biologically capable of producing babies.

Now I know what you're thinking: How did he fit into a younger man's clothes at his age and what is he going to do with the body? I'm not sure myself...

Really? You mean, women can naturally get like this?


I mean, if women do have facial hair, I didn't know it can get like that, unless there is some information missing, like explanations as to wether women can grow hair to that amount in the face as few males do as the picture illustrates or not, and if they don't, why the difference and why that notion exists.

This line in and of itself is so frequently parroted that it has become the status quo. So I shall take your advice and form a reversal. Intra-organismally, there are areas of differing hair intensity. The gonads and face are the most intensely covered. The question that should be asked is, "Why are these the only parts of the body, save the head, to escape atrophy at the hands of evolution?"

As a matter of pedantic semantics, the only studies showing an 80% loss of body heat from the head use test subjects stuffed into super-jackets/survival suits/MechWarriors/etc. Though as much as 20% of the blood in the body may be found in the head at any given time, the 80% statistic is a widespread myth akin to the theory that you should eat vitamins because most people only access 10% of their brain.

To answer my original question in this post with my original idea in this thread, the coarseness and length of pubic and facial hair may have been used as a whisker-like extension of one's ability to sense the world, leading to a survival advantage. Sure, the onset of pubic hair is a nice way to signal fertility. In addition, those males with higher levels of testosterone will, perhaps, grow more facial/pubic hair; or grow it earlier; or mature earlier. The same individuals might have higher levels of aggression, which might be not wholly recouped for by enhanced sensitive-region sensitivity. Stranger things in evolution have happened.

If that all seems unfair, hold on; I'm still going to answer the quotation.

http://my.opera.com/vrv1/blog/

Hope that link works. To paraphrase the theory, the human body has better endurance than almost all other animals. Though a human generates way more heat when running, the fact that the same human is essentially flying flat-part-first into the dry wind with previously unheard-of sweat glands turn the human body into one giant heat-dissipater. The animals which we used as prey must pant to cool down, but cannot pant when at a gallop. However many hours it took, our ancestors would chase down a gazelle or whatever until it died/stopped from heat exhaustion.

How do we know this? Well, at least one African tribe (and likely others) still use this method. And, the distant Taramahura indians of Mexico are nomadic runners by definition, each a playfully joyous contender in frequent 50-100 mile races for, as best as it can be translated into English, "s**ts and giggles". Did I mention they have almost no suicide, cancer, foot injuries, diabetes, heart disease, et freaking cetera?

To put it bluntly, we're runners by nature. It seems absurd to suggest that our loss of hair, leaving room for sweat glands and their exudate, didn't have at least some small part in our species-wide dehairification.

Shouldn't this go to the Adult forum?

No. This is science (Biology) being discussed scientifically in the science forum with a dash of humor thrown in. Nobody here is intending that you become aroused.