How does evolution explain homosexuality?

[9-10ths_Penguin]

I would say yes, precisely because it is more accepted. Remember, we're talking incidence here, not some percentage of people who might have leanings that direction but can't act on them, which has been the case throughout history until now.

How exactly do you define homosexuality? I think the most common definition is attraction for someone of the same sex, not necessarily acting on that attraction.

Or, to approach it another way: if a man is attracted to other men, but keeps this secret and (despite his orientation) dates women, eventually marries a woman, and never has any sort of romantic or sexual experience with another man, would you consider that man homosexual or heterosexual?

Personally, I'd say he's homosexual. The fact that he's more likely to come out as a gay man now than he would've been a century (or even a few decades) ago doesn't change the fact that he was gay all along.

I can clearly see how societal acceptance would make it more likely for homosexual people to be more open about their orientation. I have much more difficulty in coming up with a mechanism that would allow societal acceptance to have an effect on what gender a person is attracted to in the first place.

 

[Francine]

Or, to approach it another way: if a man is attracted to other men, but keeps this secret and (despite his orientation) dates women, eventually marries a woman, and never has any sort of romantic or sexual experience with another man, would you consider that man homosexual or heterosexual?

I don't think your scenario is possible. Bisexual men are able to "perform" with both genders, and with store-bought lubes, women don't have to "perform" at all, but clearly a man needs a minimum sort of attraction to his sex partner in order to "perform" if you gather what I mean.

 

[9-10ths_Penguin]

I don't think your scenario is possible. Bisexual men are able to "perform" with both genders, and with store-bought lubes, women don't have to "perform" at all, but clearly a man needs a minimum sort of attraction to his sex partner in order to "perform" if you gather what I mean.

There's always fantasization.

And if that doesn't work... it is theoretically possible to have a sexless marriage.

 

[Autodidact]

I don't think your scenario is possible. Bisexual men are able to "perform" with both genders, and with store-bought lubes, women don't have to "perform" at all, but clearly a man needs a minimum sort of attraction to his sex partner in order to "perform" if you gather what I mean.

I don't know, ask Mrs. Haggard.

 

[Smoke]

I don't think your scenario is possible. Bisexual men are able to "perform" with both genders, and with store-bought lubes, women don't have to "perform" at all, but clearly a man needs a minimum sort of attraction to his sex partner in order to "perform" if you gather what I mean.

Not really, though it helps a lot. When having sex with women, I found it more enjoyable if I thought about men.

 

[Sunstone]

Not really, though it helps a lot. When having sex with women, I found it more enjoyable if I thought about men.

I can relate to that... When having sex with women, I find it more enjoyable if I think about latex.

 

[Soldano16]

This one makes no sense to me. Why is it that there are any homosexual tendencies in ANY species? Where do those instincts come from and why were they not weeded out by natural selection?

My readings came across a study that related homosexual behavior in mammals to conditions of overcrowding.

So it's s defence mechanism that has evolved for the community. It could have evolved so that the sex drive was reduced in those conditions but it obviously didn't work out that way. Somehow in nature, homosexual sex evolved as the solution.

 

[Rainbow Mage]

Homosexuality may be nature's overpopulation mechanism. If the test of showing what happens when rats are overcrowded is also true for all species.

 

[Valjean]

More studies of fuction: A function for "gay genes" after all?
This sort of selection is common. Consider a wolf pack. You might have a dozen animals, but only one couple reproduces. "Why haven't wolves died out?" -- I don't hear people asking that question.

There are pawns in Nature, even throwaways. They occur for the benefit of the species. Diversity is the key to adaptation and long-term success. A physically or behaviorally homogenous species is walking on thin ice.

Apparently dysfunctional features are common: a peacock's tail, an elk's antlers -- dangerous burdens on the individuals possessing them, yet they persist.

Keep in mind that evolution functions on populations, not individuals. Traits that appear dysfunctional in individuals often benefit the success of the group or the species, and are retained.

Consider neurotic, hypervigilant baboons or chimps. They're unhappy, nervous and have poor reproductive success, but they're also the first to spot an eagle overhead or a leopard in the bushes and raise the alarm.
Oddly, a similar function has been observed, albeit indirectly, in depressed chimps. They're unsociable, low-status, socially and physically marginalized. They appear to contribute nothing -- but when experimentally removed from the group the entire band died off.

Trade-offs: In parts of W. Africa a quarter of the populationhas sickle cell trait. Such people have a variety of medical problems and would normally be considered weak or defective, but the trait confers some resistance to malaria, so in regions where malaria is endemic these otherwise defective individuals have a selective advantage. Nature's made a trade-off. In epidemic years these "weakened" individuals ensure the survival of the tribe.

Throwaways: Breed two people with sickle cell trait and your likely to get offspring with sickle cell disease. These people are seriously ill and are unlikely to survive without periodic modern medical intervention. They're 'natural throwaways'.
In order to preserve the species Nature must produce a certain percentage of "defective" individuals. As a side effect, these defectives must inevitably produce a certain percentage of seriously ill, usually terminal, offspring who will make no genetic contribution the species.

 

[Autodidact]

Homosexuality may be nature's overpopulation mechanism. If the test of showing what happens when rats are overcrowded is also true for all species.

I believe this does not conform with evolutionary theory.

 

[Im an Atheist]

This one makes no sense to me. Why is it that there are any homosexual tendencies in ANY species? Where do those instincts come from and why were they not weeded out by natural selection?

Genetic mutation or gene expression during the development of the foetus.....

 

[RitalinO.D.]

However, the rams can't tell the difference between male and female and so each ram ends up with every colour on their back as they cannot, obviously, be fertilised

One report on sheep cited below states:
Approximately 8% of rams exhibit sexual preferences [that is, even when given a choice] for male partners (male-oriented rams) in contrast to most rams, which prefer female partners (female-oriented rams). We identified a cell group within the medial preoptic area/anterior hypothalamus of age-matched adult sheep that was significantly larger in adult rams than in ewes..

Source : Homosexual behavior in animals - Wikipedia, the free encyclopedia

That would indicate that Rams can indeed determine between males and females.

Researchers found that disabling the (fucose mutarotase) FucM gene – which influences the levels of estrogen to which the brain is exposed – caused the mice to behave as if they were male as they grew up. "The mutant female mouse underwent a slightly altered developmental programme in the brain to resemble the male brain in terms of sexual preference" said Professor Chankyu Park of the Korea Advanced Institute of Science and Technology in Daejon, South Korea, who led the research. His most recent findings have been published in the BMC Genetics journal on July 7, 2010

Found this a bit interesting. Not sure what to take from it tho.