How can gayness have a genetic basis?
 

I really hope no gay posters take offence at any of the ideas kicked around below. If you are offended, please accept at least that the offence is unintentional, and don't read too much into any one of them.

I find it difficult to accept that sexuality has a genetic basis, but I see that a lot of people seem to accept it. Has this been established firmly? I remember that experimenters bred fruit flies which appeared to exhibit homosexual behaviour, but I'm not sure that this is definitive. Can someone who does think it's genetic explain why they think this?

The problems as I see them with the genetic theory go like this: If it is genetic, it is 'genome-ubiquitous' (everywhere you go, every culture has at least a knowledge of the concept). To me this implies the gene (or geneplex) is very old - older than the gene for blue eyes, say.

Nothing too controversial so far, I don't think. But then we come to the idea of reproductive fitness. At first glance, homosexuality would appear to be a very definite barrier to successful reproduction. Admittedly, gay people can reproduce, and historically they often have, but this can be argued as a function of the stigma historically attached to gayness and the oppression it has frequently encountered.

It seems pretty clear to me that gayness, while not rendering reproduction impossible, very definitely makes it somewhat less likely. And given the assumption that the gene is very old, does it not seem that less and less 'unfitness' is required for the gene to go extinct? Think of the gene's frequency as 'bankroll', generations as spins of a roulette wheel, and the 'unfitness' of the gene as the 'house edge'... it may take a while, but even the largest bankroll will eventually go broke. And even this is ignoring the difficulty of the gene spreading in the first place... if we presuppose genetic variety, where is the selective pressure to favour gayness? What kind of 'mixed strategy' could incorporate gayness as part of a successful genetic dynasty? I'm unfamiliar with any model save the 'sneaky male' hypothesis outlined briefly by Dawkins, and I'm unconvinced. Does anyone know of a better model?

I'm not satisfied with the argument that says that since gayness is alive and well, it must de facto be evolutionarily fit - this may be so if the genetic basis can be (or is) proven, but as oultined above I can't for the life of me see how.

We can, I think, dismiss recurrent mutation - current estimates vary from 5 - 15% of the population, usually hovering around ten - far too high a frequency, it would surely be unique among such mutations. And yet I've read studies correlating left-handedness with gayness; apparently one is 'ten times more likely' to be gay if left-handed, whatever exactly that figure may mean. Which of course strongly implies that there is a genetic basis...

Could it be a genetic aberration that ironically has survived precisely because of the stigma historically attached to it? (Gays disguising their gayness and thus passing on their gay genes.) Amusing to think that if Falwell and similar monsters really wanted rid of gayness, maybe they should embrace it and hope that it dies out!

The best model I could come up with for gayness having an evolutionary niche was a bit of a Goldberg, involving separate genes for male and female gayness, finding evolutionarily fit phenotypic expression in opposite genders - the gene for male gayness increasing some facet of fitness or other in women, and vice versa for the female gayness gene. The best excuse for this model I could find was the popularly-repeated notion that women are more given to gay behaviour (without necessarily being exclusive lesbians) than males... this I attributed to women lacking a Y chromosome, thus leading the 'lesbic' gene to find 'gay expression' somewhat more frequently than its male counterpart. And I have read of a theory involving genes increasing female fertility to foster gayness in men - but this I'm suspicious of. It seems to just swap the phenotypes across genders, and hey - girly-men! One thing gay men appear to be unanimous on is that they are not 'women with penises' - they are a breed apart. And while this is not strictly evidence against such a theory, I'm uncomfortable with such 'neatness' - the answer feels simple in a way that experience has led me to regard with suspicion.

So basically, after all this thinking and armchair theorising, I can't find a way to see how gayness could be evolutionarily fit, and hence can't quite accept its genetic basis - can anyone offer further insight?

Re: How can gayness have a genetic basis?
 

What if being gay happens to be a highly probable mutation for the offspring of the most evolutionarily fit?

Re: How can gayness have a genetic basis?
 

Feels like special pleading to be honest. And if gayness is accepted as an inhibitor of reproduction, in the long term, that brand of evolutionary fitness isn't all that fit. If not, then that could be a plausible model - though I'd be curious as to how.

Re: How can gayness have a genetic basis?
 

It could also be an unavoidable, rare by-product of something else. Not everything is fit. Do you think Tay-Sachs has a genetic basis?

A better question is, how could it possibly NOT have a genetic basis? I can't think of a single way besides mass global conspiracy spanning thousands of years and various species. That seems pretty unlikely to me.

Re: How can gayness have a genetic basis?
 

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the gene (or geneplex) is very old - older than the gene for blue eyes, say.

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Don't assume that something has to be selected for in order to exist. We can do calculus, even though that obviously was not selected for. Nor would there necessarily be strong negative selective pressure, since critters can both reproduce and have gay sex. Possibly, or rather, likely, some important trait that was selected for has a side effect of sometimes causing same sex attraction.

Birth order effects odds of being gay, suggesting it's not genes per se, but the womb environment, and therefore still of biological origin.

There is not a clear explanation for WHY homosexuality would emerge from genes, but there are strong indications that it does.

If I remember right, identical twins raised apart have a tendency towards having the same sexual orientation.

Oral histories of gays are very telling. Time after time in coming out stories people describe their desperate attempts to be straight, often lasting for decades. For them, it's clearly of biological origin.

Wiki on Penguins: "Male penguin couples have been documented to mate for life, build nests together, and to use a stone as a surrogate egg in nesting and brooding. In 2004, the Central Park Zoo in the United States replaced one male couple's stone with a fertile egg, which the couple then raised as their own offspring."

The Wiki entry has some interesting ideas:

http://en.wikipedia.org/wiki/Homosexuality

Re: How can gayness have a genetic basis?
 

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A better question is, how could it possibly NOT have a genetic basis

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Do scat and waddle fetishes have a genetic basis? How about strong preferences for the female beauty determined by the prevailing culture? Your ancestors used to like fat chicks.

Much of specific human behavior doesn't have a genetic basis. I'm not talking about general traits, like aggressiveness, intelligence, language ability, reflectiveness, and so on, which are largely the result of brain architecture. I'm talking about being attracted to things which have emotional and cultural significance, such as scat or waddles or beefy males.

Re: How can gayness have a genetic basis?
 

I think Our Omnipotent Lord was well aware of this problem, that's why he told to hate the Gays in the Bible.
This stigmatization forced gays to hide and marry, and have offspring.
This was only the only way to preserve the gayness gene. This plot was vrucial in human evolution, as Gays are betterlooking and much better artists.
Unfortunately, the moral decadence of our society is endangering this plan. What gay haters don't realize, is as was correctedly hinted in OP post, the tolerance for gayness in our societies will eventually lead to the demise of gayness, and consequently of fashion sense.
The future of humanity is bleak. God is punishing us again for our sins.

Re: How can gayness have a genetic basis?
 

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Not everything is fit. Do you think Tay-Sachs has a genetic basis?

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basically sums up what i was going to say.

Re: How can gayness have a genetic basis?
 

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A better question is, how could it possibly NOT have a genetic basis

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Do scat and waddle fetishes have a genetic basis? How about strong preferences for the female beauty determined by the prevailing culture? Your ancestors used to like fat chicks.

Much of specific human behavior doesn't have a genetic basis. I'm not talking about general traits, like aggressiveness, intelligence, language ability, reflectiveness, and so on, which are largely the result of brain architecture. I'm talking about being attracted to things which have emotional and cultural significance, such as scat or waddles or beefy males.

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Being attracted to fat chicks definitely has a genetic basis, at least the type of fat chicks you are talking about.

But homosexuality isn't really a specific human behavior, its more of a general one. I wonder what would happen if we did twin studies on people into scat? Not sure, but the ones we've done on homosexuality show a genetic component. We've had many discussions on these forums about the FITNESS of homosexuality, and I think that is still a controversial topic that I have no strong opinions about. But the genetic basis for it seems pretty hard to argue with.

Re: How can gayness have a genetic basis?
 

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Oral histories of gays are very telling.

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No, not really. Few people can understand and control the basis of their urges, many of which arise from something as simple a childhood experience, or wiring that gets crossed during childhood between affection and sexual attraction toward males. Why do you think it's often stated that males tend to be attracted to people like their mothers? Conditioning. And that's in normal individuals.

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Time after time in coming out stories people describe their desperate attempts to be straight, often lasting for decades. For them, it's clearly of biological origin.

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By this reasoning, child molesting is also biologically based. Yet you don't hear many people advocating that idea, even though it would be significantly more "evolutionary fit" than gayness.

The fact is that our brains are so advanced, and go through such a long period of haphazard development, that all kinds of things can get screwed up and crossed and confused, regardless of your genes. Putting it down entirely or mostly to genes (which the evidence does not support) is taking away from where the responsibility usually lies - which is with the individual.

Re: How can gayness have a genetic basis?
 

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twin studies...show a genetic component

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Sure. Many behavioral traits are partly genetic. But how large is the effect? Can you get me a %? The studies I've read only show partial correlation.

Re: How can gayness have a genetic basis?
 

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Why do you think it's often stated that males tend to be attracted to people like their mothers? Conditioning. And that's in normal individuals.

Putting it down entirely or mostly to genes (which the evidence does not support) is taking away from where the responsibility usually lies - which is with the gay.

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Or with the very ugly mother.

Re: How can gayness have a genetic basis?
 

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It could also be an unavoidable, rare by-product of something else. Not everything is fit. Do you think Tay-Sachs has a genetic basis?

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~10% = not 'rare' by my standards... The (possible) unfitness of gayness only becomes a problem if you believe the gene to be very old, which I've already said I do. My thinking is that if it is that old, it can't be unfit. Yet I can't see how it could be fit. Show gayness as a recent emergence and the problem goes away. Get me?

And while I'm not a doctor, Wikipedia certainly thinks Tay-Sachs is genetic...

"Most HEXA mutations are rare, and do not occur in genetically isolated populations..." so as a counterexample for gayness it's apples and oranges (Tay-Sachs for Gay Sex, Homosexual unfitness for Hexosaminidase A deficiency [img]/images/graemlins/laugh.gif[/img])

But the problem with the by-product theory is that the correlation needs to be weak or otherwise rare - if the link between catalyst and catamite is too strong, I don't see how the trait could spread to become ubiquitous - gayness seems to be too strong a disincentive to successful reproduction.

Forgive the puns please.

Re: How can gayness have a genetic basis?
 

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We can do calculus, even though that obviously was not selected for.

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The intellectual 'software' we use to perform those tasks very definitely was selected for, however.

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Nor would there necessarily be strong negative selective pressure, since critters can both reproduce and have gay sex.

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Indeed they can, but I don't see that they would inevitably tend to.

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Possibly, or rather, likely, some important trait that was selected for has a side effect of sometimes causing same sex attraction.

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How often would this trait occur? How could it occur with this ~10% figure we see today and still be evolutionarily fit? Even a 0.5% impedance of reproduction would have significant impact in the fulness of evolutionary time.

Re: How can gayness have a genetic basis?
 

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Why do you think it's often stated that males tend to be attracted to people like their mothers? Conditioning. And that's in normal individuals.

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Putting it down entirely or mostly to genes (which the evidence does not support) is taking away from where the responsibility usually lies - which is with the gay.

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So... due to our conditioning, we're all to blame for wanting to [censored] our mothers? I don't follow...

Re: How can gayness have a genetic basis?
 

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Oral histories of gays are very telling. Time after time in coming out stories people describe their desperate attempts to be straight, often lasting for decades. For them, it's clearly of biological origin.

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No, not really. Few people can understand and control the basis of their urges, many of which arise from something as simple a childhood experience, or wiring that gets crossed during childhood between affection and sexual attraction toward males.

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Are you conflating biological and genetic? I purposefully specified a biological basis, not a genetic. "a childhood experience, or wiring that gets crossed" are exactly the sorts of things I wanted to allow for as possible causes. By biological, I mean a powerful trait beyond choice. It might be genetically "intended," or it might be a variant in development after conception ("childhood experience" or "crossed wires"). Or both. There has to be a genetic element, but I think the post-conception explanations have momentum.

The oral histories demonstrate there is something inexorable about homosexuality, for at least many gays. This means the OP has to inquire about the biology (whether genetic or developmental or both), even though evolution makes it confusing. That was my point.

And I would say that foot fetishes and the like are also biological, in that they are intense urges emanating from brain structure, not the result of a fad or a weak, sinful will. But I think we can safely say that foot fetishes were not selected for, yet there they are.

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Many behavioral traits are partly genetic. But how large is the effect? Can you get me a %?

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Asked and answered. I'm not suggesting specific coding as the explanation.

Re: How can gayness have a genetic basis?
 

Humans evolved in largely polygynous social structures. This structure leaves most males without sexual outlets in the form of females. And most female with not enough of their male to go around for purposes other than reproduction. Homosexual tendencies would relieve a lot of social tensions in this situation.

Re: How can gayness have a genetic basis?
 

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twin studies...show a genetic component

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Sure. Many behavioral traits are partly genetic. But how large is the effect? Can you get me a %? The studies I've read only show partial correlation.

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Also consider that being in the womb together may alter or even "synchronize" their behaviours.

Re: How can gayness have a genetic basis?
 

Perhaps they would, but by the very theory you lay out, any gene causing such would inevitably fail to take hold. It's not as though there's a separate 'loser' dynasty that evolves gaynesss to cope with its inability to reproduce - if it's unable to reproduce, it dies out.

Re: How can gayness have a genetic basis?
 

I thought it was believed that the gene that caused women to be very fertile could cause men to be gay.

Re: How can gayness have a genetic basis?
 

Mmmm. You didn't read my whole post, did you?

Re: How can gayness have a genetic basis?
 

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Oral histories of gays are very telling.

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No, not really. Few people can understand and control the basis of their urges, many of which arise from something as simple a childhood experience, or wiring that gets crossed during childhood between affection and sexual attraction toward males. Why do you think it's often stated that males tend to be attracted to people like their mothers? Conditioning. And that's in normal individuals.

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Time after time in coming out stories people describe their desperate attempts to be straight, often lasting for decades. For them, it's clearly of biological origin.

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By this reasoning, child molesting is also biologically based. Yet you don't hear many people advocating that idea, even though it would be significantly more "evolutionary fit" than gayness.

The fact is that our brains are so advanced, and go through such a long period of haphazard development, that all kinds of things can get screwed up and crossed and confused, regardless of your genes. Putting it down entirely or mostly to genes (which the evidence does not support) is taking away from where the responsibility usually lies - which is with the individual.

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Phil, I don't want to get too far off track, but based on our discussions the above statements seem very much at odds with your views on neurobiology and human behavior. For example, I'm very interested in why you attribute a big role for environmental influences in development of sexual attraction and none (or close to it) for intelligence, brain size, etc.

Re: How can gayness have a genetic basis?
 

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Perhaps they would, but by the very theory you lay out, any gene causing such would inevitably fail to take hold. It's not as though there's a separate 'loser' dynasty that evolves gaynesss to cope with its inability to reproduce - if it's unable to reproduce, it dies out.

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No they wouldn't. I am sure it is all some game theory puzzle. The societies that had less internal strife due to lessened sexual tension would outcompete those that did not.

This could be passed by the lesbians, who still had to procreate with their male. Which would be likely in this scenario because polygyny is heavily tilted in reproductive favor of the female.

Also the dominant males could easily be queer as hell and still desire to reproduce with their stable of females.

For all we know we come from a species that was primarily homosexual, yet would still copulate for reproduction, and are evolving into heteros.

More likely we come from a species that would stick it in anything because their hormones raged so hard. (that sentence is so gay it proves it!)

Re: How can gayness have a genetic basis?
 

Sickle-cell anemia is a simple example of how a "bad" gene can persist. 2 copies are clearly bad, but 1 copy confers a degree of resistance to malaria. The gene actively kills some people and stops them from reproducing, but it actively helps others reproduce, so it survives.

Note: The next paragraph is pure speculation to provide an example- I have no evidence that the genetic basis of homosexuality fits this model.

Since the genetic component of homosexuality is definitely more complicated (and studies of identical twins separated at birth confirm a genetic component), let's assume we have multiple genes that come together to give a degree of predisposition toward homosexuality. If each of these genes, in the absence of the others (or the absence of enough of the others) confers an advantage, then just like the sickle cell gene, it will propagate and multiply in spite of the fact it directly causes some offspring to be unable to reproduce.

If there were exactly 1 gene for homosexuality, and it had no other effect besides a gay/straight switch, you would be correct that the trait is most likely not old (it could still get lucky and propagate for awhile), but homosexuality is obviously not the sole result of one gene with no other side effects, so your conclusion does not follow, as the two examples above show.

Re: How can gayness have a genetic basis?
 

As I suspected, this is group-selectionist thinking.

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Also the dominant males could easily be queer as hell and still desire to reproduce with their stable of females.

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Maybe you and I have different views of what constitutes 'queer as hell' - how could they be 'extremely gay' (leaving aside the problem of defining that) and still desire to have sex with the wimmens?

Your polygyny theory and the 'loser male' hypothesis would be far more likely to lead to a 'rape gene' than a 'gay gene'. I can see how it would be more successful.

Re: How can gayness have a genetic basis?
 

Interesting. I should make clear that I'm not hostile to the idea of a genetic basis, just sceptical. I am in fact surprised that this seems to be under-discussed - it cries out for an explanation.

So we accept that each element in this 'geneplex' confers a specific advantage to the organism - doesn't the ~10% figure imply (it does to me) that we're looking at a fairly small group of genes (probability people please comment if possible)? Seems likely as too large a group would probably make gayness much rarer than it appears... or it could be due to the convergence of separate geneplexes...

Does anyone have links to research on this subject?

Re: How can gayness have a genetic basis?
 

Focus more on this part:

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This could be passed by the lesbians, who still had to procreate with their male. Which would be likely in this scenario because polygyny is heavily tilted in reproductive favor of the female.

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As for the part you quoted. You are assuming its binary with your reply. There is no reason for this assumption. Could be non-exclusive genetic states for both a) want to do womens, and b) want to do mens.

As for group selection thinking I stated it wrong. It actually would work that the homosexuals would get a long better in the polygynous society because they are less sexually frustrated. The frustrated strictly hetero female may be selected against due to her behavior not being tolerated.

Re: How can gayness have a genetic basis?
 

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It actually would work that the homosexuals would get a long better in the polygynous society because they are less sexually frustrated.

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'Getting along better' is not the same as 'successfully reproducing'. As I edited above before I read this, a 'rape gene' could well do far better in your scenario. Or consider a 'wanking gene' whereby the loser males relieve their frustration by shaking hands with the unemployed... all masturbation = no frustration, but no copulation = no next generation!

Re: How can gayness have a genetic basis?
 

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Maybe you and I have different views of what constitutes 'queer as hell' - how could they be 'extremely gay' (leaving aside the problem of defining that) and still desire to have sex with the wimmens?

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You have a very very inaccurate perception of homosexuality. There are innumerable cases of gay men getting married, having children and then 'realizing' they are gay. The societal pressures to conform and raise children are immense. Not to mention the biological pressure to procreate. It is anything but hard to find gay men with biological children.

Re: How can gayness have a genetic basis?
 

Stop selectively quoting me. The unsuccessful males are irrelevant. The females dominate reproductive success in polygyny. If you don't believe me do some reading on polygyny.

Ignore the males. Males are reproductive failures in polygyny.

Females get emotional support, happiness, and sexual relief due to their lesbian relationships. Less stress and increases human longevity in all manner of ways. Therefore lesbians who tolerate, or even embrace procreation with their male are more fit in a polygynous society, than either strict heterosexuals, or lesbians who won't have reproductive sex.

Edit: and I do realize my first post explained this terribly.

Re: How can gayness have a genetic basis?
 

Capturing the Friedmans

I recommend this movie, assuming you are not going into it with even a slightly depressed state of mind. It's not just the homosexuals that are capable of chameleon-izing themselves socially and procreating.

Re: How can gayness have a genetic basis?
 

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Maybe you and I have different views of what constitutes 'queer as hell' - how could they be 'extremely gay' (leaving aside the problem of defining that) and still desire to have sex with the wimmens?

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You have a very very inaccurate perception of homosexuality. There are innumerable cases of gay men getting married, having children and then 'realizing' they are gay. The societal pressures to conform and raise children are immense. Not to mention the biological pressure to procreate. It is anything but hard to find gay men with biological children.

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There is also no reason to assume that gay is the opposite of hetero, or at a minimum no reason that gay = reproductive sexual aversion. Which seems to be the entire premise of OPs declaration of gays' unfitness.

Re: How can gayness have a genetic basis?
 

Anticipated in OP, to be honest. What I'm talking about is small tendencies, over evolutionary time-scales, will magnify effects in the genome. Suppose that gayness renders a male only 5% less likely to procreate - in the fulness of evolutionary time, this will have a profound effect. Do you doubt that gayness would tend to make a male compete with less vigour for the right to copulate with a female? Do you believe his competitors would not welcome this? Would they force their own rivals to compete all the harder? I am talking here about pre-civilisation, before codified laws and before all but the most rudimentary concepts of 'social norms' (group-selectionists note: the existence of homophobia argues strongly against the 'loser male' hypothesis, I'll explain why I think so if anyone cares).

Again, clearly there are countless examples of gays procreating - but undeniably (I think) they are somewhat less likely to - and that is what concerns me here. What I'm getting at is that if there's a genetic basis, it's emphatically not of the simple, two blue-eyed parents = blue-eyed baby type.

As to the supposed 'very very inaccurate view' of gayness - I'm not presuming to speak for or dictate the motives or feelings of contemporary gays - like contemporary straights, they are not the same as the relatively distant ancestors I'm discussing.

Re: How can gayness have a genetic basis?
 

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I am talking here about pre-civilisation, before codified laws and before all but the most rudimentary concepts of 'social norms'

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You are focusing on the male again.

For the female to win the breeding competition she merely had to look fertile and desirable enough to pass the bar for one of the breeding males who controlled all the females. Which could make her desire to have lesbian relationships lead to 0% less chance at reproduction.

Re: How can gayness have a genetic basis?
 

OK slow down. Please don't put words in my mouth.

I have not said that gay is 'the opposite' of hetero.

I have not said that gayness is unfit - I have said I do not see how it can be.

As to "no reason that gay = reproductive sexual aversion" I have to wonder who it is who actually has the 'very very inaccurate view' of gayness. I imagine (I imagine, as in, I do not know, and I doubt whether any one person, even a gay one, could provide a definitive answer one way or another) that gay people do not find, or tend strongly not to find, members of the opposite sex attractive sexually.

(5 minute pause)

Now that the gasps of shock have finally died down, can we move on from this, and away from the idea that once you find a gay man who had a kid, a lesbian who had a kid, then any curiosity about the reproductive fitness of gayness is irrefutably silenced? Because that's absolute bollocks. I am talking about tendencies over very long periods of time and I have made that about as clear as I possibly can.

I think a lot of people here are allowing the (potential) political dimension of this issue to cloud their judgement. To throw my hat into the ring, one of my best beloved aunts is a lesbian. I do not have a problem with gays. I am not trying to construct some 'reason' to hate them or look down on them or in any way impugn or call into question their right to life and liberty and all that jazz - I'm just talking about genetic theory. I sense hostility behind your words and I hope this will allay it.

Re: How can gayness have a genetic basis?
 

My only point thus far here was to make sure you were aware of where your argument was going and realize the 'homosexuals do not procreate' argument has no foundation (your statement being, "how could they be 'extremely gay' and still desire to have sex with the wimmens? [sic]").

I personally don't think we have a good enough understanding of human behavior to characterize homosexuality as an effect exclusively of either nature or exclusively nurture. The fact that straight couples produce the large majority of gay offspring is a better way to start your argument in my opinion.

Re: How can gayness have a genetic basis?
 

{Edit: It's so late it's early where I am, so I won't bother revising what follows - just bear in mind that I hadn't seen your post at the bottom of page 3 when I wrote this]

I seem to recall studies by Helen Fischer (sp?) indicating that it may be women who determine with whom they will mate - selecting the most desirable male. This could plausibly render lesbianism a genetic non-starter - as to the males, it again seems plausible that a gay male would be less likely to compete with the same vigour as a straight counterpart.

Yes the conditions are not binary, and I personally subscribe to a 'spectrum' theory of sexuality, but I find it difficult to reconcile this with a genetic basis for gayness.

Re: How can gayness have a genetic basis?
 

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I have not said that gayness is unfit - I have said I do not see how it can be.

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Fair enough.

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that gay people do not find, or tend strongly not to find, members of the opposite sex attractive sexually.

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I haven't known a lot of gay folks well enough to ask them about this. All four that I have admitted that they found the opposite sex attractive in their youth (reproductive prime). I have no idea if this is common or not.

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Now that the gasps of shock have finally died down, can we move on from this, and away from the idea that once you find a gay man who had a kid, a lesbian who had a kid, then any curiosity about the reproductive fitness of gayness is irrefutably silenced? Because that's absolute bollocks. I am talking about tendencies over very long periods of time and I have made that about as clear as I possibly can.

I think a lot of people here are allowing the (potential) political dimension of this issue to cloud their judgement. To throw my hat into the ring, one of my best beloved aunts is a lesbian. I do not have a problem with gays. I am not trying to construct some 'reason' to hate them or look down on them or in any way impugn or call into question their right to life and liberty and all that jazz - I'm just talking about genetic theory. I sense hostility behind your words and I hope this will allay it.

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I don't know why you said this in a reply to me. I haven't said anything of the sort in any of my replies.

I am saying we evolved in polygyny. In polygyny women are reproductively dominant. In polygyny it is plausible that women could be lesbian and not be any less reproductively successful. In polygyny it is plausible lesbianism would confer advantages.

If this theory were correct it would mean current society should eventually breed gayness out if it can be bread out. Hardly seems politically motivated to say that.

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I sense hostility behind your words and I hope this will allay it.

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I am not hostile. I am frustrated that I keep talking about women and you keep replying about men. But that is partly my fault for my first post which was a mess.

Re: How can gayness have a genetic basis?
 

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In polygyny it is plausible that women could be lesbian and not be any less reproductively successful.

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Again, don't see how this could be so, unless we insist either that there is absolutely no such thing as 'entirely gay' or at least that women tend to be more 'moderately' gay. Yes, I'm just going to go ahead and assume that gayness tends to reduce the desire, not necessarily to procreate (what urge are gays following when they get their gay sex on? Surely the same as the rest of us.), but to have sex with members of the opposite gender - which leads to procreation.

Your account of gays finding members of the opposite sex attractive in youth is interesting... though there are so many accounts (even of people that I know) of a child being 'unmistakeably gay' (not my phrase) from very early childhood. Seems to fuel the 'spectrum' theory.

I'm tired. Hope this will still be going tomorrow, it's an interesting discussion.

[Edit: the second half of my previous post was aimed at m_the0ry].

Re: How can gayness have a genetic basis?
 

Flynn-

Same sex preference is observed in pretty much EVERY vertebrate animal, from fish to chickens, from horses to chimpanzees. It occurs in approximately the same ratio to general population as in humans.

Yes, sexuality and gender are traits defined by, or heavily influenced by, genes. It would take a couple semesters worth of posts for me to explain all this to you. I am not saying you are unable to understand or anything like that, just that this is a very complex topic, much moreso than the blue-eyed/brown-eyed examples from high school.