Well, why do they?
And while we’re at it, how did it shake out that in most cultures throughout the world, women have worn their hair long and men (usually) wear it short?
Hormones.
Both men’s and women’s skin have the potential to grow hair (beards, chest, shoulders, etc.). If the male hormone, testosterone, is present then the hair will grow.
Most women have too little testosterone to cause such hair to grow. Some do (and others seem to be sensitive to even the trace amounts of testosterone present in normal women).
So why do women have less testosterone?
Testosterone is produced in the testicles (or phrased more properly, in the testes).
The testes can be formed only if there’s a ‘Y’ chromosome, i.e. in a male.
Fiver,
Obviously this explanation does not apply for all of the world, but a probable reason why men’s hair style tends toward being cut short is because of the Romans. Apparently short hair is harder to grab during battle, and you know the last thing you need is someone holding onto your hair while you are stabbing him.
I thought this went back to the Greeks.
Which I suspect is not really the question.
Or was it Major Kong?
That answer could be given to explain pretty much any secondary sexual characteristics. Why do women have breasts? Hormones. Why do women have wider hips? Hormones. Why so women have less muscle? Hormones. Why are women shorter? Hormones. And so on.
Of course it doesn’t really answer the deeper question. Women have breasts to feed young, or to attract males or whatever. Women have wider hips to make birth easier. Women have less hair because….?
The best theory I heard was that women have less hair because youth in mates is highly valued by men. In human males and chimpanzees of both genders the beard grows in during late puberty/early adulthood well after fertility and the development of other secondary sexual characteristics. A female who never developed beard, and yet developed breasts etc would appear too be a perpetual teenager and thus perpetually desirable, at least up to a point.
Since human body hair development seems to be related to the same triggers that cause the development of beards, women developed less body hair along with a lighter beard.
The ancient Celtic warriors wore long hair, didn’t they? You could make a long list of martial cultures where men wore long hair in the old days. Arabs, Germanic peoples, Afghans, Malays, samurai…
In the modern world the old spirit has been replaced by the sarariman man in the gray flannel suit of dull businesslike conformity. And all because of the ancient Greeks and Romans?
It’s odd that women (supposedly) feel the cold more, yet have less insulating body hair.
Don’t women feel the cold more because there is proportionally less blood in a woman’s body than in a man’s body?
Women are supposed to have more fat than men, for all the usual reproductive reasons that are generally trotted out. But maybe the extra fat is for insulation, as there is less blood in a woman.
Maybe it is only thin women who feel the cold more than men?
What is interesting is that, anecdotally speaking at least, many M2F transexuals report feeling much colder in identical situations after taking hormones than they ever did before. I am unaware of scientific analysis of exactly why.
Although I agree that women do have less hair than males, the difference is not that great as first glance. If you look very closely, you will see hair all over a womans body, it is just lighter, shorter, and thinner.
If you are looking for an evolutionary answer, I think that Blake is correct. In humans, many distictively female characteristics are also characteristics of youth. One might for example add lack of eyebrow ridges, smoother skin etc.
However, in addition to youth being more attractive as a mate, in humans it is very important that male sticks around to help bring up baby. Signs of youth may be responsible for triggering caring behaviour in a woman’s mate and in other individuals in the woman’s community. Gaining such care would greatly enhance a womans overall reproductive success.
In both women and men, the adrenal glands are also a source of testosterone. But, except for some rare genetic disorders (an XX person can have extremely productive adrenal glands, giving rise to some typically “male” traits), it isn’t a whole lot.
The case I just described, by the way, is known as adrenal hyperplasia.
Is that accurate? There has been many cultures where men wore long hair. A frank not only would wear long hair, but a vanquished or destitued ennemy would have his hair cut in order to show he wasn’t anymore a viril, proud and free man.
It’s true that it seems to me at first glance that in the majority of cultures, men tend to have their hair cut short (or somewhat short), but it’s doesn’t seem very universal.
To be more precise, the adrenal glands are the source of androgens (male hormones) of which testosterone is a very, very minor component. The predominant adrenal androgen is dihydroepiandrosterone sulfate. It is this androgen which causes pubic and axillary hair growth even in the absence of testes, eg. in a pubescent girl. It is a very weak male hormone, though, as evidenced by the fact that 11-year-old girls can have pubic hair from its effect, but no beard or chest hair (!). Conversely, this also reflects the inherent sensitivity of the pubic and axillary regions to even small amounts of androgens.
In adrenal hyperplasia, there is an enzymatic block in the production of cortisol. Things “back up” and “spill over” into androgen production. In severe cases, a female fetus can be masculinized even before birth, or a two-year-old boy can wield a six-inch penis and a full bed of pubic hair.
I don’t think it’s the same for women of all cultures, but in the USA it seems to be “traditional” for women to shave their legs and armpits. If you’re American, Major Kong, is it possible that you think women have less hair than men because you have’t seen women of other cultures (who perhaps don’t shave) sufficiently unclothed?
