Sexual selection in humans.

[A trickle of science]

Most sexual selection between species consists of the female being choosy, to find the perfect mate to offer her offspring the best chances in life for survival and to reproduce.

 

However, in humans and other species the male also embarks into the parental offering resources, support increasing the child's chances to develop successfully.

 

So, my question is that due to most males carrying out a parental role, does this mean that males have evolved certain instincts to also become choosy looking for certain aspects and characteristics found in other females?

[Unity+]

Most sexual selection between species consists of the female being choosy, to find the perfect mate to offer her offspring the best chances in life for survival and to reproduce.

 

However, in humans and other species the male also embarks into the parental offering resources, support increasing the child's chances to develop successfully.

 

So, my question is that due to most males carrying out a parental role, does this mean that males have evolved certain instincts to also become choosy looking for certain aspects and characteristics found in other females?

I think all species evolved to have sexual attraction to mates that have the best features, or fit enough features, for going about reproduction. It goes both ways rather than females being the only "choosy" ones. Males may have less(or more, it depends on the individual) specification as to the strictness of such features, but both sides have their requirements.

[Delta1212]

I think all species evolved to have sexual attraction to mates that have the best features, or fit enough features, for going about reproduction. It goes both ways rather than females being the only "choosy" ones. Males may have less(or more, it depends on the individual) specification as to the strictness of such features, but both sides have their requirements.

I do think there is a greater selection pressure on males in many species, however, because the reproductive cost in terms of resources spent and time taken out of the reproductive cycle for each instance of reproduction is generally higher for females than it is for males.

 

There is less evolutionary cost to a male choosing a bad mate than there is for a female, because it's easier for a male to quickly move on to a more optimal one than it is for a female.

[Ken Fabian]

I think social/cultural mores have to play a big part with humans and expect those played a part through much of our hominid history - and they will work against any one universal criteria for sexual selection. Even notions of what is attractive can vary widely and I'm not sure that 'beautiful' people, advantaged as they clearly are, have been shown to be better breeders than 'ordinary' ones, even if there can be rejected 'ugly' people who do have poorer reproductive success. there are other criteria, like social status (which may equate to wealth) and thus better capability to provide for their young. Or proven ability - the woman who's dilly bag comes back fuller than others from a morning's foraging or the better hunter or better crafts person who's products are prized. Not that this excludes more direct and brutish competition - the forceful, dominating male that takes the women he wants and beats the crap out of any competitors; I've witnessed behaviour like that, with the woman involved having little say and, in hindsight, also subject to intimidation. I suspect that cultural rules that minimise or ritualise that more brutal competition led to more lasting success for the community.

 

Mate selection is often not a choice of young man or woman but of parents, community leaders, assigned matchmakers etc. Individuals choosing for themselves, much as we 'westerners' currently value such 'free' choice, may be the exception. Even though I expect there would still be competition it's not confined to individuals or personal attractiveness.

[Lyudmilascience]

yea I think both genders look for good traits or characteristics in each other. they are choosy in trying to find a woman who can take care of the young and is fertile.

[MEC1960]

Sexual selection is a major driver of evolution and was one of two mechanisms first put forward by Darwin (the other being Natural Selection). It manifests itself in hugely varied ways in all sexually reproducing organisms. Even in plants; orchids are the birds of the plant kingdom in this regard - where sexual selection can yield extreme differences.

 

In humans there is evidence of sexual selection. For example, most animals experience periods of estrus (sexually receptive behavior -called lordosis- accompanied by ovulation) that occurs often in very proscribed intervals. Humans (as well as our close cousins the orangutans and bonobos) undergo concealed ovulation - that is we do not show signs of estrus even when ovulating (though often the woman knows). This in humans and bonobos, though probably not in orangs, may be a sexually selected trait as concealed ovulation is a way to ensure that males stay around or it may be beneficial in group behaviors. Other possibly sexually selected traits in humans include large prominent mammaries in females, relative hairlessness in females, long hair on the head and face of men, facial structures, etc.

 

Here's the thing....it is difficult to disentangle most traits from sexual dimorphism. That is there may be other reasons, examples of natural selection, for some or all of these traits. The truth is likely that sexual differences in humans are driven by a spectrum of influences from primarily sexual selection to primarily natural selection. In many birds it is obvious; a peacock's tail is a strong negatively selected trait in terms of natural selection - they cannot easily escape predators when their tails are set for display. Peahens are not under that kind of selection. It is clear that it is very strongly sexually selected trait as peacocks are willing to risk their survival to enhance their chances of reproduction. Compare that to sexual traits in humans. Is the shape and robustness of the male jaw a sexually selected trait or is it an example of natural selection? It is difficult to come up with evidence in support of either (or rather, what evidence there is supports both).