So why do men have nipples?

[ittarter]

And as for your comment earlier about so far ahead or behind, that'd be the later.

Ouch!

I know. Let's have an I'm-right-you're-wrong war. First person to say it a thousand times, wins.

btw I didn't say anything about earlier or later. Spellcheck reveals English flunkies once again! Hurrah!

 

[ittarter]

From Human Origins 101, by Holly M. Dunsworth. p. 21.

"Nipples on male mammals are not vestigial traits, as they do not signal an ancient state of male milk production. Male nipples are simply the result of an interesting developmental process. All humans begin development as a female and not until about the seventh week does an embryo with a Y chromosome start developing as a male. This transition occurs after the development of the mammary glands underneath it. Male nipples are simply stamps in the mammalian passport of development."
​

Everything but the last sentence fits. How'd we move from genetics to a "passport of development"?

 

[Washington]

Everything but the last sentence fits. How'd we move from genetics to a "passport of development"?

I haven't the faintest. I think the author just got carried away in her metaphorical prose.

 

[JediMobius]

I like my nipples, I'm glad God saw fit to give them to men as well. haha, titillating. . . oh and Washington, your chimpanzee disturbs me, I don't really know why. . .

 

[Washington]

I like my nipples, I'm glad God saw fit to give them to men as well. haha, titillating. . . oh and Washington, your chimpanzee disturbs me, I don't really know why. . .

Neither do I. . . . .family resemblance perhaps??







Actually, one person told me the chimp's apparent comprehension of evolution, and his ability to convey that understanding, was a little unnerving.

 

[JediMobius]

Actually, one person told me the chimp's apparent comprehension of evolution, and his ability to convey that understanding, was a little unnerving.

Hahahahaha, that's awesome.

 

[juvenissun]

evolution predicts vestigial organs and parts. your straw man has been discovered.

Fine. But are the vestigial organ diminishing with time?

 

[LifeToTheFullest!]

Fine. But are the vestigial organ diminishing with time?

Yes. Just like ID.

 

[juvenissun]

Yes. Just like ID.

If yes, why do we (men) still have nipples? Are they getting smaller through time?

 

[MoonLancer]

Fine. But are the vestigial organ diminishing with time?

wont happen because of sexual selection. girls like the nipple.

 

[ranmaonehalf]

...
Also, how else would a guy know when it's cold outside?

This post is absolutely titillating, no?

well they could check for shrinkage...

 

[MrGoodBytes]

If yes, why do we (men) still have nipples? Are they getting smaller through time?

Male nipples aren't selected against. They are useless, but not a liability.

 

[LifeToTheFullest!]

Male nipples aren't selected against. They are useless, but not a liability.

If you only understood ToE a little better! If they are vestigial, why are they still there????!!!??? Shouldn't they have disappeared by now?






















JK

 

[Wiccan_Child]

If yes, why do we (men) still have nipples? Are they getting smaller through time?

Doubtful: they'd only get smaller if there was any reason for them to. Since there's no real detriment in male nipples, there's no selection pressure affecting them.

 

[juvenissun]

Male nipples aren't selected against. They are useless, but not a liability.

Does every animal have more or less one or more useless organ? If so, why are we not loaded with useless (but not liable) organs?

 

[LifeToTheFullest!]

Does every animal have more or less one or more useless organ? If so, why are we not loaded with useless (but not liable) organs?

I don't know if "every animal have more or less one or more useless organ". Maybe they do, maybe they don't. Non-issue really.

Why do think we should be loaded with useless organs? Please explain, I do not understand what you mean.

 

[Naraoia]

Doubtful: they'd only get smaller if there was any reason for them to. Since there's no real detriment in male nipples, there's no selection pressure affecting them.

They could also get smaller because there was no reason for them to get bigger.

Hmm... do all male mammals have nipples?

 

[Hespera]

The inner ear bones of a human being are vestiges of a reptile jaw articulation.
The jaw is a vestige of what was once a gill arch.
And so on...

In the absence of an absolutely clear definfinition for "vestigial" and the lack of a bright line distinction between that which has some (known) use and that which does not, it makes it hard to make absolute statements about vestigial structures.


Every animal has something of its history written into its structure.

Quite possibly the male nipples are linked to some gene in a way that makes them very difficult to eliminate. They dont cause any problems anyway, so no selective pressure against them, the way there is for wisdom teeth, or would be if we didnt have dentists.

I think Juv has some sort of idea he is getting at with regard to vestigial organs. I hope he will just state it clearly, rather than asking cryptic questions.

 

[Wiccan_Child]

They could also get smaller because there was no reason for them to get bigger.

But likewise, they could get bigger, because there's no reason for them to get smaller. Overall, they stay the same, no?

Hmm... do all male mammals have nipples?

I'd imagine so, though there's probably some obscure species of field mouse whose males don't get nipples .

Does every animal have more or less one or more useless organ? If so, why are we not loaded with useless (but not liable) organs?

Vestigial traits tend to adopt some other function than their original, if only because a useful vestige is better than a useless one. Problem is, male nipples are so pointless that there's not much they can be adapted for.

Whale legs have lost their primary role, but have adopted a secondary, supportive role: they help with the reproductive system. They're vestiges, but they are retained because they have some useful function, however minor.

 

[pgp_protector]

They could also get smaller because there was no reason for them to get bigger.

Hmm... do all male mammals have nipples?

No.
platypuses has no nipples (Mail or Female)
Mail horses don't have them (That I know of)
Also some times men (and women) can be born without nipples.
Breast Cancer 101 - Breast Anatomy

So no, not ALL male mammals have nipples.