Natural Selection and Homosexuality

[Indecent]

I'm pretty firm in my belief that homosexuality, is, in someway, genetic. I've read a few studies that lean this way as well, and I also think that the documentation of over 1,500 species exhibiting homosexual lifestyles is not something that can be ignored.

Some theories include:
-It is a widespread gene which gets activated in a proportion of people randomly but nearly everyone is a carrier, including the heterosexuals.
-There are a lot of genetically bisexual people who de facto live heterosexual lives for social reasons.

We already know that sometimes our sex organs don't completely develop before we're born; some people are "assigned" the wrong sex. What if its similar with a sexual orientation gene? What if our bodies got mixed signals in sexual orientation the same way it can get mixed signals in the sex a baby should be?

For example - if your DNA can give you ovaries and then somehow "forget" and give you a penis to go along with it, why can't it give you a penis and then "forget" and give you an attraction towards men?

*****I also like to remind those of us who've forgotten their high school biology course of the Hardy-Weinberg equilibrium: Even if a gene is completely lethal (to either the species or the individual animal/plant), so long as it is recessive, it will remain.
I see this often, as our family owns a horse farm. There is a type of horse called the "lethal white". Many, many horses carry the lethal white gene, and they live perfectly normal, healthy lives as the gene is recessive. Mate a stallion and a mare that both carry it, though, and you'll have a foal that dies within the week because they are missing a crucial part of their intestines.

This gene will not further the species, but it exists, and will continue to exist because it is recessive. I think with a better understanding of DNA in the future, that we'll hit upon the answer that will prove to everyone that discrimination against sexual orientation is no different from discrimination because of race or gender.

 

[rivrrat]

Well, it's certainly not a choice, but I'm not sure it's genetic either. Unless our sexual preferences in general are genetic... like, a preference for tall partners, or dark hair, or blondes, etc, etc. Or just what we find attractive *period*. We like what we like.. I can't really see how that could be genetic, but maybe it is.... I dunno.

 

[Just Me 2]

I don't believe that it is a choice I'm not so sure about a gene though. I tend to lean more towards receiving either to much testosterone or progesterone before birth. Every person's male/female chromosomes are there from the moment of conception and as the baby grows the mothers body sends hormones to the baby based on the sex. If the child is male it will receive more testosterone if female more progesterone. I think what happens is the body of the mother may be confused and sends to much of the opposite hormone to the baby. I have zero proof of this it is just my theory. .

 

[Indecent]

I hardly think making a lifetime commitment to another person (whether of the same sex or different sex) can be based on a proliferance of hormones.
Not only is that not giving the person enough credit ("you dont really love your partner, you just have too much estrogen"), it just isn't realistic in a scientific way. Women and men on high doses of steroids or hormonal supplements then would suddenly change sexual preference, and there are also no studies that show that gays have different hormone levels from the next straight individual, either.

 

[Just Me 2]

I hardly think making a lifetime commitment to another person (whether of the same sex or different sex) can be based on a proliferance of hormones.
Not only is that not giving the person enough credit ("you dont really love your partner, you just have too much estrogen"), it just isn't realistic in a scientific way. Women and men on high doses of steroids or hormonal supplements then would suddenly change sexual preference, and there are also no studies that show that gays have different hormone levels from the next straight individual, either.

I guess you missed the part where I said I have zero proof of this it is just my theory.

I do think it is something that happens during the development of the baby but as I said I am not sure. I don't think it is a gene.

 

[Indecent]

I guess you missed the part where I said I have zero proof of this it is just my theory.

I do think it is something that happens during the development of the baby but as I said I am not sure. I don't think it is a gene.

I wasn't haranguing you for proof, for pete's sake. I don't have proof one way or another either, and was just offering an opinion on your theory, as I was asking for on mine. Which would be the reason I posted this in the first place.

 

[Gunface]

Well, it's certainly not a choice, but I'm not sure it's genetic either. Unless our sexual preferences in general are genetic... like, a preference for tall partners, or dark hair, or blondes, etc, etc. Or just what we find attractive *period*. We like what we like.. I can't really see how that could be genetic, but maybe it is.... I dunno.

I do believe that physical attractiveness is governed genetically to an extent. I've read a lot about it, please correct me if I'm wrong.

Richard Dawkins explains sexual selection (which has very much to do with this) very well. Basically, if a male animal with red feathers and a female that prefers red feathers mate, the child will likely be either red feathered (if it's a male) or prefer red feathers (if it's a female). So basically, as soon as red feathered animals become even slightly more populous than blue-feathered ones, they'll continue to be the majority.


But yeah. It's a fun idea.

Obviously homosexuality isn't a choice. I mean, come on. Who would choose this? It's not so fun most of the time. Who would be like "Hmm. I feel like being a homosexual today!"? No one. I'm not quite sure what it is that "decides" it, though. I don't actually care too much. I know it's not a choice, so I don't care much more than that. It's not actually something that interests me too much: Why am I gay? All I really care about is that I *am*.

 

[Australianlibertarian]

I would have to say that in part homosexuality is most likely genetic. But I wouldn't put a bet that you are going to see a single gay gene isolated by scientists. The most likely explanation will be that in some individuals, genes that influence sex-preference and or brain development will show different expression patterns to heterosexual individuals. The big question is when will these expression patterns occur? Is it during puberty, during development during the womb?

I suppose from an evolutionary stand point, many of us are wondering how homosexuality could be genetic, when by definition homosexuals can't reproduce..... Well my argument would be that genetics of homosexuality survived because homosexuals throughout the millenia pretended to by hetrosexual to avoid persecution. Resulting in offspring that may have been homosexual themselves, or possible carriers of homosexual influencing genes. There is another part of me that thinks that the influence could be environmental, because what we see as people, or animals is the interaction between the organism's genes and their environment (phenotype). So maybe there are certain genes that can increase the probability of homosexuality, but you need certain environmental factors to actually be homosexual or bi-sexual (refer to Freud).

What I love most is that the agrument for either genes, or environment (or a combination of both) really puts cold water on religious fundementalists......

Think about it.... If God hates homosexuals so much, why did he design organisms that can easily become homosexual via mutations in their genetic make up, or due to influences in their environment (or a mixture of both)? It seems that the creator that hates gays so much, was pretty crap at preventing his organisms form becoming the very abimination that he so despises.......

 

[Thinker]

I suppose from an evolutionary stand point, many of us are wondering how homosexuality could be genetic, when by definition homosexuals can't reproduce.

They can and do - just not with others of their sex.

Well my argument would be that genetics of homosexuality survived because homosexuals throughout the millenia pretended to by hetrosexual to avoid persecution.

I think that's unlikely. While homosexuality has been observed in natural
conditions in an ever-increasing number of species, I know of only one that
persecutes homosexuals: humans.

It seems far more likely that homosexuality has either an evolutionary benefit
of which we are not aware or is a side-effect of some other useful genetic
trait (perhaps increased female fertility).

What I love most is that the agrument for either genes, or environment (or a combination of both) really puts cold water on religious fundementalists......

You don't need sex to do that. They spout so much utter nonsense almost
anything they say shows them to be deluded.

 

[rivrrat]

I do believe that physical attractiveness is governed genetically to an extent. I've read a lot about it, please correct me if I'm wrong.

Richard Dawkins explains sexual selection (which has very much to do with this) very well. Basically, if a male animal with red feathers and a female that prefers red feathers mate, the child will likely be either red feathered (if it's a male) or prefer red feathers (if it's a female). So basically, as soon as red feathered animals become even slightly more populous than blue-feathered ones, they'll continue to be the majority.


But yeah. It's a fun idea.

Obviously homosexuality isn't a choice. I mean, come on. Who would choose this? It's not so fun most of the time. Who would be like "Hmm. I feel like being a homosexual today!"? No one. I'm not quite sure what it is that "decides" it, though. I don't actually care too much. I know it's not a choice, so I don't care much more than that. It's not actually something that interests me too much: Why am I gay? All I really care about is that I *am*.

This makes sense and while I can't really argue with it I do have a question. Is Dawkins suggesting that there's a "red feather gene", per se?

For instance, is there a gene that gives me my proclivity towards tall partners?

I'm not a geneticist by any stretch of the imagination. All I know about genes is what I was taught in Advanced Biology regarding dominant and recessive genes, etc. But I find it difficult to believe that there's an actual gene responsible for my sexual preferences. However, I do think that most of them I was born with. (One I definitely know I was ) If there's not a specific gene responsible, could it still be genetic? This is a question based solely on genetic ignorance. LOL

It seems far more likely that homosexuality has either an evolutionary benefit
of which we are not aware or is a side-effect of some other useful genetic
trait (perhaps increased female fertility).

Or male fertility. It's an observed scientific fact that (heterosexual) male desire and possibly fertility increases when watching lesbians. *nods*

 

[rivrrat]

It seems far more likely that homosexuality has either an evolutionary benefit
of which we are not aware or is a side-effect of some other useful genetic
trait (perhaps increased female fertility).

Or male fertility. It's an observed scientific fact that (heterosexual) male desire and possibly fertility increases when watching lesbians. *nods*

 

[rivrrat]

It seems far more likely that homosexuality has either an evolutionary benefit
of which we are not aware or is a side-effect of some other useful genetic
trait (perhaps increased female fertility).

Or male fertility. It's an observed scientific fact that (heterosexual) male desire and possibly fertility increases when watching lesbians. *nods*

 

[Gunface]

This makes sense and while I can't really argue with it I do have a question. Is Dawkins suggesting that there's a "red feather gene", per se?

For instance, is there a gene that gives me my proclivity towards tall partners?

I'm not a geneticist by any stretch of the imagination. All I know about genes is what I was taught in Advanced Biology regarding dominant and recessive genes, etc. But I find it difficult to believe that there's an actual gene responsible for my sexual preferences. However, I do think that most of them I was born with. (One I definitely know I was ) If there's not a specific gene responsible, could it still be genetic? This is a question based solely on genetic ignorance. LOL

I'm supposing there has to be a "red feather" gene, as well as a "prefers red feathers gene" for the female. Of course, this is oversimplified.
It could be a whole network of genes, all interrelated, but the effect is the same.

 

[Indecent]

I suppose from an evolutionary stand point, many of us are wondering how homosexuality could be genetic, when by definition homosexuals can't reproduce.

This would be addressed from the genetic theory I posted in the start of the thread.
That even if a gene would kill off a species, it will continue to exist if it is recessive:

Hardy-Weinberg equilibrium: Even if a gene is completely lethal (to either the species or the individual animal/plant), so long as it is recessive, it will remain.
I see this often, as our family owns a horse farm. There is a type of horse called the "lethal white". Many, many horses carry the lethal white gene, and they live perfectly normal, healthy lives as the gene is recessive. Mate a stallion and a mare that both carry it, though, and you'll have a foal that dies within the week because they are missing a crucial part of their intestines.

 

[rathi]

Twin studies show that homosexuality is most likely genetic. Concepts like homosexuality are difficult to study in humans though, as controlling for societal factors is very difficult. Even getting accurate data on a person's actual feelings is hard.

 

[Duke]

I'm pretty firm in my belief that homosexuality, is, in someway, genetic. I've read a few studies that lean this way as well, and I also think that the documentation of over 1,500 species exhibiting homosexual lifestyles is not something that can be ignored.

Some theories include:
-It is a widespread gene which gets activated in a proportion of people randomly but nearly everyone is a carrier, including the heterosexuals.
-There are a lot of genetically bisexual people who de facto live heterosexual lives for social reasons.

We already know that sometimes our sex organs don't completely develop before we're born; some people are "assigned" the wrong sex. What if its similar with a sexual orientation gene? What if our bodies got mixed signals in sexual orientation the same way it can get mixed signals in the sex a baby should be?

For example - if your DNA can give you ovaries and then somehow "forget" and give you a penis to go along with it, why can't it give you a penis and then "forget" and give you an attraction towards men?

*****I also like to remind those of us who've forgotten their high school biology course of the Hardy-Weinberg equilibrium: Even if a gene is completely lethal (to either the species or the individual animal/plant), so long as it is recessive, it will remain.
I see this often, as our family owns a horse farm. There is a type of horse called the "lethal white". Many, many horses carry the lethal white gene, and they live perfectly normal, healthy lives as the gene is recessive. Mate a stallion and a mare that both carry it, though, and you'll have a foal that dies within the week because they are missing a crucial part of their intestines.

This gene will not further the species, but it exists, and will continue to exist because it is recessive. I think with a better understanding of DNA in the future, that we'll hit upon the answer that will prove to everyone that discrimination against sexual orientation is no different from discrimination because of race or gender.

I believe that this is a possibility, but for lack of any real evidence support it, I don't necessarily believe it's true. Good food for thought, though.

There's so much we don't know about behaviorial genetics and the causes of behaviors anyway, it's really hard to speculate.


Duke

 

[paulmarkj]

I suppose from an evolutionary stand point, many of us are wondering how homosexuality could be genetic, when by definition homosexuals can't reproduce.....

This isn't true, in fact you answer, in part, yourself:

Well my argument would be that genetics of homosexuality survived because homosexuals throughout the millenia pretended to by hetrosexual to avoid persecution.

We talk of homosexuality in terms of lifestyle, but in evolutionary terms all that matters is whether you reproduce or not - your sexual preference may not alter this much. Oscar Wilde had two children, so do many hetrosexual men. Those two times Oscar had sex with a woman were the only ones that counted (for evolution).

A man may have hetrosexual sex 10,000 times with 100s of women, but if he only has one child, then compared to Oscar Wilde, he is less successful.

 

[rivrrat]

Twin studies show that homosexuality is most likely genetic. Concepts like homosexuality are difficult to study in humans though, as controlling for societal factors is very difficult. Even getting accurate data on a person's actual feelings is hard.

Do you think that sexual preferences are nutured? (re: the "societal factors")

I'm not talking about *just* homosexuality, IMO that's only a part of the equation. I'm applying this hypothesis (possibily incorrectly) to all or most sexual preferences. Liking blondes, or red-heads.... preferring large breasts, or small.... preferring a muscular build, or a non-muscular build... so on and so forth. We all know what gets our juices flowing as far as *physical* characteristics go. We all have our preferences of what we find attractive, what draws us toward someone, what makes our head turn in the middle of that crowded bar. Even after that, we have preferences in attitudes too... what kind of attitude we find sexy and appealing. And further than that, we have preferences in how we enjoy sex.... slow and gentle, fast and rough, so on and so forth.

Are those preferences nature or nuture, do you think? And, do you separate such preferences from homosexuality in general?

I'm not picking on you, rathi... it's just that you implied a "nuture" possibility to homosexuality. I'm just curious what folks think about all sexual preferences and if folks feel homo/heterosexuality falls in a completely different category than other sexual preferences.

 

[Thinker]

Do you think that sexual preferences are nutured? (re: the "societal factors")

Social pressures clearly do influence behaviour, but I view this as a relatively
minor effect on top of the basis provided genetically. This is similar to the
particular language one speaks being less important in evolutionary terms than
the physical attributes that allow speech of any sort.

 

[Indecent]

Do you think that sexual preferences are nutured? (re: the "societal factors")

I'm not talking about *just* homosexuality, IMO that's only a part of the equation. I'm applying this hypothesis (possibily incorrectly) to all or most sexual preferences. Liking blondes, or red-heads.... preferring large breasts, or small.... preferring a muscular build, or a non-muscular build... so on and so forth. We all know what gets our juices flowing as far as *physical* characteristics go. We all have our preferences of what we find attractive, what draws us toward someone, what makes our head turn in the middle of that crowded bar. Even after that, we have preferences in attitudes too... what kind of attitude we find sexy and appealing. And further than that, we have preferences in how we enjoy sex.... slow and gentle, fast and rough, so on and so forth.

Are those preferences nature or nuture, do you think? And, do you separate such preferences from homosexuality in general?

I'm not picking on you, rathi... it's just that you implied a "nuture" possibility to homosexuality. I'm just curious what folks think about all sexual preferences and if folks feel homo/heterosexuality falls in a completely different category than other sexual preferences.

I guess, for me anyway, there is a large difference between gender preference and other sexual preferences.
For example, my roommate has a huge thing for blondes, but has been dating a redhead for three years - they're sure to get engaged recently. He has a preference, but it doesn't overcome "love" and real relationships.
Hetero vs Homo, though, is a far different ballpark from blonde vs brunette. I know its rather simplifying things in that sense, but I don't have the werewithal today to delve into it.
The gays I know have no interest in the opposite gender sexually anymore than a stout straight does. But having a sexual preference for blondes doesn't mean they _only_ date blondes. The two, to me, are apples and oranges. Faint similarities, but very different.

 

[rathi]

Are those preferences nature or nuture, do you think? And, do you separate such preferences from homosexuality in general?

You horribly oversimplify behavioral genetics. Almost every single trait has multiple causes. Sex is significantly influence by genetic and environmental influences. And there is no reason to separate homosexuality from any other sexual preference, at least genetically speaking.

Social pressures clearly do influence behaviour, but I view this as a relatively
minor effect on top of the basis provided genetically.

Society has extremely powerful influences on sex. American society frowns upon 24 year olds having sex with 14 year olds. Thus such instances are fairly rare. However, we are biologically designed so that such an act is normal and highly beneficial. Society clearly overrides genetics in this case.

The gays I know have no interest in the opposite gender sexually anymore than a stout straight does. But having a sexual preference for blondes doesn't mean they _only_ date blondes. The two, to me, are apples and oranges. Faint similarities, but very different.

Societal pressure has significant impact on gender choices. Strong messages are sent to pick one gender or the other. For example, girls in America, especially the college students , have relaxed standards for gender preference. Making out with other girls doesn't mean that the girl is treated as a lesbian. They still primarily choose men, but still kiss other girls, sometimes in attempt to get more attention from men. However, most other societies would conclude that making out with other girls would make that girl a lesbian.

 

[rivrrat]

Society has extremely powerful influences on sex. American society frowns upon 24 year olds having sex with 14 year olds. Thus such instances are fairly rare. However, we are biologically designed so that such an act is normal and highly beneficial. Society clearly overrides genetics in this case.

Societal pressure has significant impact on gender choices. Strong messages are sent to pick one gender or the other. For example, girls in America, especially the college students , have relaxed standards for gender preference. Making out with other girls doesn't mean that the girl is treated as a lesbian. They still primarily choose men, but still kiss other girls, sometimes in attempt to get more attention from men. However, most other societies would conclude that making out with other girls would make that girl a lesbian.

Ah.. but in these cases you are talking about sexual actions, not desires. Two very different things. I cannot control my attraction to someone, but I can control what I do or do not do with regard to that attraction.

In the case of a 24 yr old and a 14 yr old. Society may frown on it, so the elder chooses not to act on his/her desire. But the desire itself is still present.

Do you believe that the desire itself is socially influenced?

 

[rathi]

Do you believe that the desire itself is socially influenced?

Of course. Different culture can influence what people desire. For example, in Victorian times, the ideal sexy women had far more fat than the current standards of today. Also, things like schoolgirl or nurse uniforms also clearly come from society.