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Why do men have nipples?

by wasteofo2
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wasteofo2
#1
Dec1-03, 09:51 PM
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Well? And do the males of other species have nipples?
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iansmith
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Dec1-03, 10:09 PM
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Originally posted by wasteofo2
Well? And do the males of other species have nipples?
I have seen nipple on male gorilla and chimp but i never saw nipple on a male dog or cat. The fur could in the way. The nipple is probably just a left over part from the X-chromosome. Technically mammals starts as a female in the embryo state.
wasteofo2
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Dec1-03, 10:15 PM
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Originally posted by iansmith
Technically mammals starts as a female in the embryo state.
Oh god, Gary Busey was right... "Men are just failed women at birth."

Could you elaborate on that please?

russ_watters
#4
Dec1-03, 10:27 PM
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Why do men have nipples?

Originally posted by iansmith
I have seen nipple on male gorilla and chimp but i never saw nipple on a male dog or cat. The fur could in the way. The nipple is probably just a left over part from the X-chromosome. Technically mammals starts as a female in the embryo state.
Yes, all male mammals have nipples. Your guess would be mine as well.
Chemicalsuperfreak
#5
Dec2-03, 02:24 AM
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Redundancy. Give everybody the same basic plumbing and let the hormones decide who gets what. The nipples that prepubescent girls have are physiologically identical to male nipples, then when the hormones kick in they develop into full grown breasts. The same general concept can be applied to why females have a clitoris and labia. If the right hormones are expressed (in the womb instead of puberty) you end up with a penis and a scrotum, respectively.
zoobyshoe
#6
Dec2-03, 02:24 AM
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Very, very strange. They serve no purpose at all, do they. I hadn't ever thought about it before.
fstam2
#7
Dec2-03, 02:42 AM
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There has been a case where in a species of bat, the male can lactate to feed it's young. Now I feel that is very interesting.
Todd
Mentat
#8
Dec2-03, 10:01 AM
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Originally posted by fstam2
There has been a case where in a species of bat, the male can lactate to feed it's young. Now I feel that is very interesting.
Todd
I agree. You know there was a thread a while ago, that I can't seem to find for some reason, which talked about a few instances wherein a male human was able to breast feed his children...now that was bizarre.

Can anyone locate that thread?
Monique
#9
Dec2-03, 10:25 AM
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A female embryo (XX) exposed to testosterone in the womb will have male physiology.
Mentat
#10
Dec2-03, 10:28 AM
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Originally posted by Monique
A female embryo (XX) exposed to testosterone in the womb will have male physiology.
Hmm...I don't know how to ask this exactly, but, has that ever been linked to why some women are homosexual from birth? If so, is the opposite case (the lack of testosterone in the womb) the cause of homosexual men?
BoulderHead
#11
Dec2-03, 11:00 AM
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Originally posted by Mentat
I agree. You know there was a thread a while ago, that I can't seem to find for some reason, which talked about a few instances wherein a male human was able to breast feed his children...now that was bizarre.

Can anyone locate that thread?
Mentat. I seem to recall that thread.
What I had once read was that a man who had his nipples sucked on for 20-30 minutes at a time, several times each day, began to lactate after a period several months. I believe the story was genuine, but of course I could be mistaken.


Originally posted by wasteofo2
Well? And do the males of other species have nipples?
Because men need all the erectile tissue they can get.
Monique
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Dec2-03, 11:19 AM
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Originally posted by Mentat
Hmm...I don't know how to ask this exactly, but, has that ever been linked to why some women are homosexual from birth? If so, is the opposite case (the lack of testosterone in the womb) the cause of homosexual men?
Very good observation! I thought I would include that in my reply, but didn't. Researchers are definately interested in looking at the effects of testosterone on the developing brain, which may cause the 'I am in the wrong body' feeling.
revesz
#13
Dec3-03, 09:12 PM
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I have heard that women who take steroids(male hormones), will grow a beard and moustache. With enough use there clitoris will begin to form into a small penis(oh god no!)

If your a male, and you take birth control pills(female hormones), you will begin to develope breast and other female characteristics.
Monique
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Dec3-03, 11:22 PM
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Yes, that is true: secondary sexual organs are induced by hormones too.

There is also a disease called the Androgen Insensitivity Syndrome, where a person is born with the male (XY) chromosomes but is intersexual. 95% of intersexual people have mutations on a X-linked gene, which cause them to be insensitive to the male hormone testosterone and thus not develop the sexual organs normally in the womb (they will be infertile).
adrenaline
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Dec4-03, 02:33 AM
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This brings up a nice seguay into the biology of homosexuality as Mentat brought up. Some neuroendocrine psychologists have found that women with congenital adrenal hyperplasia ( thus their in utero environment has higher testosterone exposure) have a much higher propensity for homosexuality. http://www.boskydell.com/political/outlooks.htm also http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract
http://www.findarticles.com/cf_0/m03...le.jhtml?term= the latter is a 14 page discussion of the many studies.

Thus, is homosexual behavior dependent on the in utero hormonal milieu? Men who have complete androgen insensitivity ( internal undescended testicles, blind vaginal pouch) are in every way women and more likely to be attracted to men. By the way, these women ( because they have grown up as women until a physical exam at puberty to assess for why they are not menstruating) are very, very feminine and physically attractive. (remember, estrogen receptors have mild cross over sensitivity to testosterone and other androgens and when overstimulated by the huge doses of circulationg androgens, they exert all the estrogenic developmental patterns.) These women have to have their undescended testicles removed to eliminate the high chance of testicular cancer that occurs with undescended testicles. To show how very attractive they are there is a very famous, attractive, actress in Hollywood who is a confirmed complete androgen insensitivity syndrome (was a case study at UCLA, and Cedar Sinai Caalifornia) I won't divulge her name although it may be circulated already.

As for the studies on male homosexual brains, we all have probably heard of simon LeVay's work on the preoptic nucleus of the anterior hypothalamus. However, I think most clinical researchers have a problem with his work due to the fact that most of his autopsy subjects were HIV infected men and we now know how profoundly the Aids virus can change and affect the brain.
Phobos
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Dec4-03, 12:47 PM
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more information about why men have nipples...
http://www.straightdope.com/classics/a1_093.html
chroot
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Dec4-03, 01:43 PM
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Blind vaginal pouch? Sounds lovely. So do the undecended testes. Oh, and I don't really think Jamie Lee Curtis is that hot. You're telling me Jamie Lee Curtis is a MAN? Chromosomally-speaking?

- Warren
Monique
#18
Dec4-03, 04:56 PM
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Originally posted by chroot
[B]Blind vaginal pouch?
There is no uterus.
Oh, and I don't really think Jamie Lee Curtis is that hot. You're telling me Jamie Lee Curtis is a MAN? Chromosomally-speaking?
That could very well be an urban legend :) and probably is..


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