Why do men have nipples? But seriously though. Why?

Answer 1

Because our sex is only determined in the late weeks of pregnancy. We are all essentially female...with males, the clitoris forms into the head of our penis.

Answer 2

To tell you the truth, nobody really knows. The best explanation I've been able to find (and frankly it doesn't explain very much) is that nipples aren't a sex-linked characteristic. In other words, nipples are just one of those sexually neutral pieces of equipment, like arms or brains, that humans get regardless of sex.

As you may know, every human being gets a unique set of 23 pairs of chromosomes at conception. These fall into two categories. One pair of chromosomes determines sex--the XX combination means you become female, the XY combination means you become male.

The other 22 pairs, the non-sex chromosomes (they're called autosomes), supply what we might call the standard equipment that all humans get. These 22 pairs constitute an all-purpose genetic blueprint that in effect is programmed for either maleness or femaleness by the sex chromosomes. The programming is done by the hormones secreted by the sex glands.

For example, the autosomes give you a voice box, while the sex hormones determine whether it's going to be a deep male voice or a high female voice. Similarly, the autosomes give you nipples, and the sex hormones determine whether said nipples are going to be functioning (in females) or not (in males).

One interesting consequence of the developmental set-up just described is that during the very early stages of fetal life, before the sex hormones have had a chance to do their stuff, all humans are basically bisexual. Among other things, you have two sets of primitive plumbing--one male, one female. Only one set develops into a mature urogenital system, but you retain traces of the other for the rest of your life.

It's tempting, therefore, to say that male nipples are yet another vestige of your carefree bisexual youth. Trouble is, male nipples are hardly vestigial. They're full-sized and fully equipped with blood vessels, nerves, and all the usual appurtenances of functioning organs. Why this should be so nobody knows--in some other mammals, such as rats and mice, male nipple development is completely suppressed by the male sex hormones. (Incidentally, don't start thinking that at one time our human male ancestors must have suckled their young. So far as anybody knows, male lactation has never developed in any mammalian species.)

Human nipples appear in the third or fourth week of development, well before the sex characteristics. (The sex hormones start to assert themselves at seven weeks.) As many as seven pairs of nipples are arranged along either side of a "milk line," a ridge of skin that runs from the upper chest to the navel.

Normally only one pair amounts to anything, but on about one baby in a hundred you can detect some vestige of the other ones, usually on the order of a freckle. There are cases of women who ended up with an extra breast, which made them freak show candidates not so many years ago. Luckily today the women can avail themselves of corrective surgery while the rest of us can watch Jenny Jones.

Anyway, both male and female babies are born with the main milk ducts intact--the gland that produces milk is there in the male, but it remains undeveloped unless stimulated by the female hormone, estrogen. Occasionally, a male baby is born with enough of his mother's estrogen in his body to produce a bizarre phenomenon known as "witches' milk," with the male glands, suitably stimulated, pumping away at the moment of birth.

In the adult male, the dormant glands can still be revived by a sufficient dose of estrogen. Actual lactation is rare--only a couple cases have been recorded. But at least one writer (Daly, 1978) has suggested that the "physiological impediments to the evolution of male lactation do not seem individually surmountable." Meaning we may yet see the dawn of the truly liberated household.

Answer 3

If the female baby of a guy have been to handle a number of his dominant constructive factors, including hair colour, eye colour, and particular, nipple definition (there are all styles of nipples obtainable, some are inverted, some are huge, some have important areola ...all styles of constructive factors and adjustments) lady baby are no longer carbon copies of their mothers.

Answer 4

Men and women evolved from the same egg. They go their different ways only way out there.

Answer 5

Because at the stage where babies develop those features male and female are pretty much the same.

Answer 6

Everyone starts life as a female.

Answer 7

the same reason they have a gall bladder, or a little toe. they are vestigial organs.... of no use anymore. evolutionary left overs.

Answer 8

Because they have breasts...just part of how the upper body of humans is designed...

Answer 9

I think it's because they would look funny without them. Good question.

Answer 10

have you ever had your nipples sucked, flicked or bitten while you where having sex