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From an evolutionary perspective, why do women have bosoms?

  1. Sep 10, 2009 #1
    We've all heard people from time to time in their conversations ask about this riddle. Many say that they're all fat and don't know why men care about them, etc.

    This is what some think evolution says, plus some alternative views. I like to test ideas. What's everyone's take on this? :

    There is no relationship with bosom size/shape and the amount of baby milk one can produce, and the other primates don't have permanent bosoms like humans do. However, there's a relationship between sexual maturity and size/form (too old and they're not shaped as well and too young, you get the point). Because of this, many zoologists and evolutionary psychologists think they evolved out of sexual selection, just like a male peacock's feathers get in his way but say to the females, "Come here good looking!"

    On the other side of the coin, some opponents to sexual selection point out there's no relationship between bosom size and how likely a woman is to get married. They say that if it's sexual selection, then you'd expect it would give a woman an advantage in obtaining a mate. They say most of the time sexual selection is actually in the males in the animal kingdom, since most females who live long enough will mate, while quite a few of the males never get to score (mammals and birds). They also point out how the majority of human females who live long enough find some kind of partner.

    So what's your opinion so far? Any insights? Since bosoms are just fat and many social conversations are curious about the answer to this riddle, why do men like them, and why do women have them? Keep in mind there's no relationship between size/milk potential, and also getting married, and the other primates only have them when nursing rather than permanently.

    So, what if we were to go at this question from a different angle? I have an idea of my own and a way to make it scientifically falsifiable. I need some feedback here. Here goes .... Women tend to look for men with nice cars and lots of diamonds! Just kidding! I meant there's some interest in resources there. What if it's possible that there was a population bottleneck in the course of human history, some think there was? What if during times of famine having a male partner who had lots of resources had an evolutionary advantage for the woman and her kids? Maybe we could say "Women have permanent bosoms unlike other primates because they gave a distinct sexual selection advantage during times of severe famine because they could get the men with the better resources" rather than just sexual selection, since most who make it to the right age find a mate anyway?

    Just like someone tests their car/sink after fixing it, maybe we could test our theory? Any ideas? I think probably the easiest way to make it possible to be falsified would be to see if there's a relationship between bosom shape/size and how much money a woman's husband earns? Yes, I know you couldn't go around doing that. However, just like scientists say there's no relationship between size and milk, maybe those in the "medical field" who handle that could be bribed with research money into testing our idea by doing an extensive survey where they find out how much their patients' husbands make? Although correlation doesn't prove causation, we could control for as many third variables that seem reasonable, and see if there's still the relationship. Although we can't prove, do you think that would make it falsifiable and count as a logical consequence? I was also brainstorming the possibility of looking at genes responsible for permanent bosoms and seeing if the estimation for these certain genes evolving coincide with certain bottleneck/widespread famine dates scientists may be aware of.

    Enough about my thoughts, what does everyone else here think about our hypothesis? Any other ideas on why men are attracted to them and why women have them?
  2. jcsd
  3. Sep 10, 2009 #2
    The male has evolved to find the female form arousing to encourage reproduction. The female form evolved to have wide hips for child bearing and larger breasts (than males) for lactating. In response, males evolved an attraction towards larger breasts and wider hips. This then created a selective pressure for women to have even wider hips and larger breasts.
  4. Sep 10, 2009 #3
    Why do men have nipples?
  5. Sep 10, 2009 #4


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    Staff: Mentor

    So why do most men prefer small hips and butts?
  6. Sep 10, 2009 #5
    women with small boobs are usually unattractive.
  7. Sep 10, 2009 #6
    Did it occur to you that it might be related to the probability for them to feel unconfident ?
    Which men ? There are certainly places where this is not a true statement. For instance, Europe middle ages. Maybe our current societies placed a high value a while ago to taking care of one's own health, for instance not allowing oneself to become too fat. As time goes, some men may associate thin women with healthy women, or at least women who have enough free time to take care of themselves and exercise. I do not claim this is a true correlation, I claim it is possible that some men make the correlation in their head, possibly unconsciously.
  8. Sep 10, 2009 #7
    This, pretty much. Larger fuller breasts are a sign of health and fitness. Women who have aged(younger women are less likely to have fertility issues), suffered disease, ill health, or lack of nutrition will likely have withered breasts. While small breasts may not necessarily be any indication of lacking health or fitness neither do they indicate any greater health or fitness so they would be less likely to be selected for.
  9. Sep 10, 2009 #8
    I have heard of a more specific theory. When we were not standing yet, we were attracted by what we now could call "bottoms". The size of the female breasts developed (according to this theory) after we began to stand up. I unfortunately do not recall any reference, and I can not remember how credible this argument was. Maybe they did have bone quantitative indication to support this idea.
  10. Sep 10, 2009 #9
    Many women complain that having big boobs hurts their chest, and lower back. Some have even undertaken a breast reduction surgeries.
  11. Sep 10, 2009 #10
    I think women prefer small hips and butts. There have even been studies that show men prefer a lower waist to hip ratio.

    Edit: And if you look at most mens magazine covers you will see the evidence.
  12. Sep 10, 2009 #11
    desmond morris wrote about that. i don't know if he was the first to point that out or what
  13. Sep 10, 2009 #12
    Men still prefer large hips and butts relative to size of hips and butts of other males. You are using the word "small" in reference to the average modern women, which is much more overweight than what we would have evolved an attraction for.

    It is no surprise that when you take the ideal biological woman and replace her active lifestyle with a sedentary one, and make food a commodity that even the poorest person can afford in abundance, their resulting body shape is no longer the same as in the history of evolution.
  14. Sep 10, 2009 #13
    I think men like large bosoms because they're more noticeable - they stick out and men look at them. It could be that simple. Men react more to visual stimuli than women.

    As for small hips and butts (how shall I phrase this), the perfect female form (for many men) is the one with the "natural spread" as it's called. That is, when a woman stands with her legs straight and together at the knees, you can see between her thighs (from the front or rear) to the other side - just below her private areas. This is the aspect of "wider hips" that men may cite.

    On the other hand, if the female is full figured, it is not apparent. At that point, a different set of criteria is appreciated.
  15. Sep 10, 2009 #14
    Care to back-up that needlessly insulting commentary?
  16. Sep 10, 2009 #15
    I'm generally more attracted to smaller breasted women. It just gets to a point with the big ones where it's like enough is enough already.
  17. Sep 10, 2009 #16


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    Staff: Mentor

    I'm thinking of models and actresses, they all have no hips or butt, if they do, like Jennifer Love Hewitt, they are ridiculed.

    I have no hips or butt and men love it. Yes you can see between my legs because they are so thin. Nothing to do with the width of my hips. And I have large breasts.
  18. Sep 10, 2009 #17
    In "The Best Songs Ever" thread there is a rap video (by Drake - Best I Ever Had) smothered in big, bouncing breasts. Too much!
  19. Sep 10, 2009 #18
    I'd like to say "maybe you have for some reason not met the men who are not attracted by the features you describe" but for some reason, after what you've just said I agree with you anyway :tongue2:
  20. Sep 10, 2009 #19
    I can tell you for a fact that women with bigger breasts get more tips (including from me) at the strip club. Survival of the fittest.
  21. Sep 10, 2009 #20
    yeah, i am an *** man, and i just don't get this small butt thing. i think it's mostly a neurosis. some of it is hollywood- and other celebrity-driven. women tend to have excellent shape when they are young, fertile, and in excellent physical and hormonal condition. that can make for a short career as a sex-symbol. they get older and their boobs deflate and sag. they can do a lot of exercise now and bring the hips/thighs down, but this then requires a boob job to complete the look. they may not even have hips now because they're older, the hormonal situation is worse, and fat stores in other places that have to be slimmed down. so small butt, and big fake boobs.

    then there are other things. fewer women breastfeed now. breastfeeding has interesting effect: it pulls fat off the thighs.

    some also blame media types like Hugh Heffner for promoting more masculine female types, and claim that the women in his magazine have more masculine features now than in its early days. as further evidence, they observe that Heffner has now admitted that he has experimented with bisexuality. maybe that's an age-related thing, it certainly seems to happen to congressmen often enough.

    evolutionarily, i find the mimicry of the buttocks interesting. but more than that, it takes a lot of time and energy to raise up healthy human children. the breast makes a convenient place to store up extra reserves for lean times, and it's in a convenient place for the male to observe and make a mate selection. spread out across the body, it would be less obvious.
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