[IceFire]

The second one is more Darwinistic, I'm not a biologist so I'm not really familiar with this, but what advantages could there be for any species to turn a certain amount of its population to homosexuals?

Darwinistic discussions are always interesting if you take it at a strictly academic level which I hope remains in this thread.

I have read it postulated that homosexual behavior is an "advantage" because a certain proportion of the society is "less inclined" to breed offspring and therefore keeps the population levels in check.  I don't remember all of the rationale but on some levels that could make sense.  Its probably far more complicated than that and as I said thats a strictly academic view of things.

[MP-Ryan]

I'm quoting two separate posts because the reply applies to both:

now given that this behavior/personality trait is incompatible with, or at the least a hinderence to, sexual reproduction, in the long run fewer people with the "gay gene" will be having children and thus fewer still being born.

I have read it postulated that homosexual behavior is an "advantage" because a certain proportion of the society is "less inclined" to breed offspring and therefore keeps the population levels in check.  I don't remember all of the rationale but on some levels that could make sense.  Its probably far more complicated than that and as I said thats a strictly academic view of things.

Homosexuality persists mainly because it is not subject to strict Mendelian inheritance patterns.  For those of you who have forgotten high school biology, that means that homosexuality is NOT a single-gene phenomenon, and it is NOT confined to autosomes (everything but X and Y).

Quantitaive trait locus study for homosexuality-related genes have highlighted at least 4 different chromosomes in humans, including the X chromosome.  Note that these studies are thus far confined to male homosexuals only.  There are multiple regions containing multiple genes on each of these chromosomes that appear to be involved.

What that means is that homosexuality is not strictly inherited.  The complexity also means that normal genotypic variation and mutation during the course of reproduction will produce new mutations that result in homosexual phenotypic traits.

Homosexuality really provides no selective advantage - it's just a spontaneous condition that emerges as a result of the way sexual reproduction occurs.  A certain proportion of homosexuals can be expected purely due to random chance in any given population.  Resource scarcity and other explanations that bring in evolutionary arguments aren't really relevant.  It's like asking why Tay Sachs disease still exists if every individual born with it dies (and we'll ignore the fact that tay Sachs is also recessive, which complicates it further) - you always have a certain number of new mutations that can produce a disorder, and you'll always have carriers that are susceptible to but not affected by a genetic condition.

Please note I'm not medicalizing homosexuality either - it's normal phenotypic variation in any population.

As an aside, from the research out there my personal theory is that homosexuality arises in humans from errors with gene silencing, particularly on the X chromosome, which directly affects neuronal development.

[Bobboau]

'gay gene' was in quotes because I was makeing an extreme simplification to make my point clearer.

[Edward Bradshaw]

Please note I'm not medicalizing homosexuality either - it's normal phenotypic variation in any population.

As an aside, from the research out there my personal theory is that homosexuality arises in humans from errors with gene silencing, particularly on the X chromosome, which directly affects neuronal development.

Isnt it also true that homosexuality has been linked to chemical imbalences in the womb during pregnancy? Which might also account for some cases.

[TrashMan]

Meh...I'm not getting dragged into another debate like this. I netiher have the time nor the will. There was a time I would defend my views over the internet vigorously...but I just don't care anymore. Maby I'm just geting old.

Think of me what you wish, write about me what you wish, call me by whatever name you fancy...

[Flipside]

On a slightly different tangent, I've always wondered about the 'Far Right Dilemma', i.e. if it was discovered that homosexuality could be discovered before birth, but could not be reversed, where would the far right stand on abortion?

I get visions of heads exploding over that one.

[MP-Ryan]

Isnt it also true that homosexuality has been linked to chemical imbalences in the womb during pregnancy? Which might also account for some cases.

I don't think so.

What you're probably thinking of is gender identity.  The type of brain that develops in a fetus (be it male, or female) depends on the hormones its exposed to... androgens or estrogens.  It is possible for a female brain to accidentally be exposed to androgens, and vice versa.  It is also possible that while the brain is exposed to the right hormones, the rest of the body isn't.  The end result is sexual characteristics that do not agree with either (1) genotype (e.g. XX males, XY females), or (2) personality.

Transsexuality is a developmental condition where you get a brain that is sexually opposite in identity from the body, for whatever reason.  It happens surprisingly often.  It's also in part due to there being no male or female threshold - we don't really have two sexes, but rather variation between two sex extremes, so we develop on a sex continuum rather than a dichotomy.

What's interesting is that sexual orientation is not linked to sexual identity - you get female-to-male transsexuals that are still attracted to men.  You also get female-to-male transsexuals that are attracted to women.  The same holds true for male-to-female.

While all that is very interesting from an inquisitive biological point of view, the end result is that everyone has a different personal sexual identity and different personal sexuals attractions.  So long as it doesn't actually harm anyone, who am I to tell someone who they can do what with?

Of course, the minute you throw moral dogma courtesy of religion into the mix, some people start making claims that its unnatural, but the fact of the matter is its perfectly natural and perfectly normal, and its been with us since mammals evolved, possibly even before.

[Flipside]

Oddly enough, even the Fox News site states that several animals engage in homosexuality, and they, I would have thought, would have been loathe to admit something like that....

http://www.foxnews.com/story/0,2933,316316,00.html

[Agent_Koopa]

On a slightly different tangent, I've always wondered about the 'Far Right Dilemma', i.e. if it was discovered that homosexuality could be discovered before birth, but could not be reversed, where would the far right stand on abortion?

I get visions of heads exploding over that one.

I think that the far right would still disallow abortion. You see, they don't actually advocate killing gays, they just want gays to have sex with women.

[Fearless Leader]

...
This is something you usually hear from homophobes.
...

usually they say "Stay away from me you homo"
or "Im going to f****** stab you"
or "IF YOU HUG ME AGAIN IM GOING TO KILL YOU"

but hey, everyone has a different experience, right?

[Hazaanko]

...
This is something you usually hear from homophobes.
...

usually they say "Stay away from me you homo"
or "Im going to f****** stab you"
or "IF YOU HUG ME AGAIN IM GOING TO KILL YOU"

but hey, everyone has a different experience, right?

Hay!  Those are things I say on a day-to-day basis!

[karajorma]

That's what alcoholics refer to as "A moment of clarity"

Make of it what you will.

[Macfie]

There are indications from some statistical studies that alcoholism is genetic.  Just because there is a genetic tendency does not mean it is not a choice.

[Edward Bradshaw]

There are indications from some statistical studies that alcoholism is genetic.  Just because there is a genetic tendency does not mean it is not a choice.

Yes it is, its the very opposite of choice. You dont choose to be genetically predisposed to getting hooked on alcohol. You can choose not to let yourself get hooked in alcohol by not drinking, and in the same way you can choose not to have sex with someone of your own sex, but that doesnt mean you arent homosexual. People choosing to be celibate doesnt mean they arent hetrosexual either.

[Flipside]

On a slightly different tangent, I've always wondered about the 'Far Right Dilemma', i.e. if it was discovered that homosexuality could be discovered before birth, but could not be reversed, where would the far right stand on abortion?

I get visions of heads exploding over that one.

I think that the far right would still disallow abortion. You see, they don't actually advocate killing gays, they just want gays to have sex with women.

Good answer, though, I hope this situation never arises, I've heard vague stories about attempts to 're-educate' homosexuals in facilities, kind of brings up images of Psi-Corp for some reason.

[MP-Ryan]

There are indications from some statistical studies that alcoholism is genetic.  Just because there is a genetic tendency does not mean it is not a choice.

Alcoholism is a genetic predisposition to respond in certain ways to the physiological effects of alcohol.  It's not a personality trait.  Different proposition altogether.  Alcoholism is reinforced by neural pathways - the genetic correlates of alcoholism are in brain chemistry, not behaviour.  Homosexuality, by contrast, exists before reinforcement.

Substance abuse predispositions, much like certain disease predispositions, function in an entirely different way from personality traits.  Substance abuse issues and degenerative conditions based on external stimuli require reinforcement to become a problem.  Personality traits require no reinforcement whatsoever to develop.

[Edward Bradshaw]

It's a genetic fluke, and nothing to be encouraged. I don't have to explain further.. take it as you wish

You said your dislike of homosexuality has little to do with your religion. So, what other reasons are there? Figures you couldnt come up with any argument against homosexuality at all.

[Mika]

Regarding Darwinism and random mutations causing homosexuality, I find it a little hard to believe at the first time. Why? Because when you think about different defects (what is actually the correct word?), one might get something like toes grown together, extra fingers, the eyes with different colors, intestines being flipped horizontally (mirror image) and things like these. But they are relatively rare on grand scale. If the reason for homosexuality is a misread gene, why is it so sensitive (10% of population being homosexuals?), while other genes are not?

According to my understanding, most of animals have their sexual organs quite well protected and all animals go to extreme lengths to reproduce. It seems quite strange to have a mutation in the most important thing of the species, namely reproduction, while other bodily functions are genetically cross-checked.

If the percentage is lower, say 2-3 %, then I might believe mutation as a explanation.

Mika

[MP-Ryan]

Regarding Darwinism and random mutations causing homosexuality, I find it a little hard to believe at the first time. Why? Because when you think about different defects (what is actually the correct word?), one might get something like toes grown together, extra fingers, the eyes with different colors, intestines being flipped horizontally (mirror image) and things like these. But they are relatively rare on grand scale. If the reason for homosexuality is a misread gene, why is it so sensitive (10% of population being homosexuals?), while other genes are not?

First off, everything you listed there except eye colour isn't caused by genetic mutation, it's caused by developmental defects - in essence, gene expression goes awry in particular tissues during development resulting in the visual effects we see.  It's not heritable.

According to my understanding, most of animals have their sexual organs quite well protected and all animals go to extreme lengths to reproduce. It seems quite strange to have a mutation in the most important thing of the species, namely reproduction, while other bodily functions are genetically cross-checked.

If the percentage is lower, say 2-3 %, then I might believe mutation as a explanation.

Homosexuality isn't a result of a genetic alteration of the reproduction system - it's misdirection of the reproductive impulse.  In short, your sex drive is reprogrammed to respond to a different stimulus.  It's not surprising considering the plasticity of the human sex drive anyway - most people have quite a range of sexual stimuli; that range differs by individual.  Some people get turned on by members of the opposite sex; some people get turned on by shoes the opposite sex wears; some get turned on by cars; still others get turned on by people of the same sex.  Sexual urges aren't by any means static even psychologically.

Now, homosexuality is something that probably results from disruption of neural pathways in multiple locations; in short, someone with a normal variable genotype gets a mutational hit in a critical neural pathway and now their intepretation of sexual stimuli shifts to the other sex.  It may also result from erroneous gender identification.

Consider that, biologically speaking, homosexuality is just a misdirection of a correct sexual response to a biologically incorrect sex.  There are all kinds of neural pathways that could mess that system up.

Homosexuality is probably a two-hit phenomenon; meaning that you have natural carriers in the population that carry a genotype very close to that which results in homosexuality, and all it takes is a single mutation to knock the system out of whack.  This happens with cancer all the time, and many immune disorders, so it's really not rare.

Any condition should result from spontaneous mutation roughly 1/100,000 times; if the condition is not mal-adaptive, it can quite easily be passed dormant through generations and spread in carrier populations before being reactivated by another mutation much later.

Homosexuals don't lose the ability to reproduce; they merely have a misdirected (biologically) sexual drive.  That's not something that's going to undergo a lot of selection pressure in evolution, especially considering that it hasn't weeded out of lower taxa of mammals long before now.

[Mefustae]

Good answer, though, I hope this situation never arises, I've heard vague stories about attempts to 're-educate' homosexuals in facilities, kind of brings up images of Psi-Corp for some reason.

Pray the gay away?