the gay gene?

[iamthedinger]

Recently an intolerant cunt by the name of victoria jackson has been featured on different media outputs because of her comments against any and all things "gay". all of her comments seemed to be geared towards the bible. this american woman seems to have forgotten about what america was founded on in regards to religious freedom and seems to want to persecute people that don't fit into what she sees as "gods plan". i think she should just take the step towards extremist and join the westboro baptist church where she'll undoubtably be welcomed with open arms as she is um a...celebrity...ish. but this post isn't all about this intolerant biotch and more about what thought process her comments seemed to have triggered in my uneducated brain. so here goes..

more often then not, people that speak out against homosexuals always seem to refer to it as a lifestyle choice. since i'm lazy and tend to not look up references to the areas i will try to address i will just express this as a theory that i've developed in my..again uneducated brain..without any actual scientific influence from any study that may have already addressed what i'm thinking.

my thoughts on the matter are this. male and females of presumably all species are attracted to each other through a seemingly complicated process that tends to initially support natural selection. we first see a woman or man that we find attractive. whether it be symmetry of bodily features, or features that we tend to find favorable. i seem to be attracted to women with blonde hair and blue eyes for some reason. after the initial attraction between two individuals, other factors play a role in whether the two end up together or repel each other. these factors can include personality, a pleasing voice, at home lifestyles. i'll use my relationship with my wife as an example of how i became attracted to her.

when i met my wife i found her physically attractive. this wasn't based on her overall physical appearance though, as i met her in basic training, the wear and fit of a military uniform isn't exactly complimentary to a woman's looks...unless you're into that kind of thing. once we started talking to each other, we seemed to pit our personalities against one other and found that we were attracted to each other's dispositions and outlooks on life in general. another thing that i found attractive is her desire to provide and take care of the people she loves. knowing this i knew that she would make a great mother and would take great care in raising a child. this she has proven exponetially (sp?) as she is raising our son while i've been deployed to kuwait. all of these attractions are measurable to anyone who pays attention to them. i paid attention during the entire process of our courtship and our marriage that followed. (5 year anniversary was 3 days ago as of this posting btw) but what isn't measurable is the chemical attraction towards one another.

we know that our bodies give off a natural scent. we use this knowledge to make ourselves smell better through the use of cologne, perfumes, lotions, deoderant, and so on. although we try to mask our natural scent with what we perceive to be more pleasing, we can't ignore the underlying chemicals and how we react to them. of course i'm referring to pheromones. so where the hell am i going with this you might ask? well if you're still following along, please continue to read. and if you have any input for any of this information..references to studies done on the subject, please let me know. i would love to know if my half baked theory actually holds merit.

there must be something in our dna that controls both the output, and reaction to, the pheromones that our bodies omit. so on a genetic level, would a mutation of the gene that controls how we react pheromones cause a person to be attracted to a member of the same sex, not only on a physical level, but a chemical level as well? this whole idea is to understand that not all homosexuals have chosen a lifestyle that makes them favor the same sex. are some people just born with it? i do understand that some people may favor same sex relationships based on prior experience, but if on a genetic level, if someone has a mutation of the gene that controls how are bodies react to members of the opposite sex, that would cause them to be attracted to a member of the same sex.

i almost feel like i'm rambling incoherently...and i blame adhd for that.

basically i'm saying that there has to be something in the bodies chemistry that controls our chemical attraction to other people. some people are born with the reactions that would be seen as typical, meaning attracted to the opposite sex. some people may be born with the reaction of being attracted to the same sex.

i'm not sure how to explain it further...please see my above statement of me being uneducated and lazy. if you understand what i'm trying to say then kudos to me.

where would this fit into natural selection?

well, that's simple enough. if two members of the same sex are attracted to each other and have no interest in the opposite sex, well they won't reproduce under normal circumstances will they? in todays world that doesn't have to be the case as children can be conceived through no sexual contact but in the animal kingdom, this gene wouldn't be passed on to any next generation since gay dogs, for instance, don't have the capability to reproduce through homosexual activities (btw i've seen a gay dog before. the gay dog tries to mount a straight dog and it usually ends with a doggy hate crime...or a hose).

and i'll also say that gay people seem to make great parents. i think this stems from a better understanding of what human love is and better care and love is given to children that are raised by gay parents. at least that's how i've seen it in my experience. if a gay couple does not want to conceive a child through natural or unnatural means, adoption is a popular choice and one that i back completely, since as i stated above, there seems to be a better understanding of our human emotions that control our love and care.

if you've made it this far i'll say in closing..there's nothing wrong with being attracted to members of the same sex...it may even be encoded in your dna.....just don't try to hit on me please :lol: i am very happily married.




oh and if you want jokes...i got jokes.
let them get married! they should have every right to be as miserable as any other married couple in the world! :facepalm:



for references to my education please see the requirements for your state for a GED. i will be attending college but umm...i'm a late bloomer? (also see: doesn't use proper grammar, punctuation, spelling, or capitalization)

and again any input into any type of study that may have been done on this subject is very welcome.

 

[Sparky]

where would this fit into natural selection?

I personally find it a little bizarre that people try to see where natural selection comes into homosexuality. To me this seems like asking how Down's Syndrome is beneficial to someone's reproductive chances. Quite frankly it isn't (as far as I know). This doesn't prevent people from continuing to be born with the Syndrome though does it?

Anyhow if someone can point out why people try to find some benefit of homosexuality in terms of natural selection then I would be interested to know the reason.

Here is the Wikipedia article on the subject. Whether it is of any relevence - well I'm not entirely sure:

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

 

[iamthedinger]

where would this fit into natural selection?

I personally find it a little bizarre that people try to see where natural selection comes into homosexuality. To me this seems like asking how Down's Syndrome is beneficial to someone's reproductive chances. Quite frankly it isn't (as far as I know). This doesn't prevent people from continuing to be born with the Syndrome though does it?

Anyhow if someone can point out why people try to find some benefit of homosexuality in terms of natural selection then I would be interested to know the reason.

Here is the Wikipedia article on the subject. Whether it is of any relevence - well I'm not entirely sure:

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

natural selection, the process in which favorable traits are passed on to future generations. down syndrome, a defect where a child is born with an extra chromosome, number 21 i believe, would be pretty difficult to pass on. if you know someone with down syndrome you may find that they don't function on the same social level as people that were not born with the disease. they may not have any type of understanding of reproduction, depending on how severely they're effected. they may have sexual urges that they do not understand and i'm sure that in today's society, if they are biologically able to reproduce, it just might happen. before modern understanding of disorders, people with down syndrome would simply be branded as retarded and would either be destroyed or ostricized from normal society. either way, their chances of passing on any type of genes is pretty slim.
when people think of homosexuality, i don't know if they feel that this is only a human occurance. i can safely assume that it is not. it may not always be a choice made by the individual. like my reference to having seen a gay dog...it happens in nature. not just to humans. why would i point out how a possible mutation in a gene that would control individual attraction to other members of the same species apply to natural selection? i don't know, maybe i was just trying to point out the validity of the argument of what could possibly be a mutation that i obviously stated that i have done no personal research on and had just formulated the thoughts based on what i know about basic life functions.

i actually find it kind of insulting that you would try to compare homosexuality and down syndrome in how they would relate to natural selection.

two members of the same sex find each other attractive, they have no intention on conceiving a child with a member of the opposite sex, they don't pass on any of their genes to a future generation, whether there actually is a mutation or not. i'm just saying that if there is a mutation of a gene that controls attraction....well gosh they're less likely to pass that mutation on...and take into consideration that i'm not just talking about humans. humans are not the only species that are attracted to one another through chemical reactions from pheromones.

and thanks for the link...

 

[iamthedinger]

Sexual practices that significantly reduce the frequency of heterosexual intercourse also significantly decrease the chances of successful reproduction, and for this reason, they would appear to be maladaptive in an evolutionary context following a simple Darwinian model of natural selection,on the assumption that homosexuality would reduce this frequency. Several theories have been advanced to explain this contradiction, and new experimental evidence has demonstrated their feasibility.[43]



This paragraph was taken out of the link you just sent me....btw

 

[Laurens]

Is homosexuality found in reptiles, and other less social animals? Or is it something unique to social mammals?

 

[iamthedinger]

Is homosexuality found in reptiles, and other less social animals? Or is it something unique to social mammals?

LizardsWhiptail lizard (Teiidae genus) females have the ability to reproduce through parthenogenesis and as such males are rare and sexual breeding non-standard.[74] Females engage in sexual behavior to stimulate ovulation, with their behavior following their hormonal cycles; during low levels of estrogen, these (female) lizards engage in "masculine" sexual roles. Those animals with currently high estrogen levels assume "feminine" sexual roles.

Lizards that perform the courtship ritual have greater fertility than those kept in isolation due to an increase in hormones triggered by the sexual behaviors. So, even though asexual whiptail lizards populations lack males, sexual stimuli still increase reproductive success.

From an evolutionary standpoint, these females are passing their full genetic code to all of their offspring (rather than the 50% of genes that would be passed in sexual reproduction). Certain species of gecko also reproduce by parthenogenesis.[75]

this paragraph was taken from the wikipedia article found here:
http://en.wikipedia.org/wiki/Homosexual_behavior_in_animals

 

[Laurens]

Is homosexuality found in reptiles, and other less social animals? Or is it something unique to social mammals?

LizardsWhiptail lizard (Teiidae genus) females have the ability to reproduce through parthenogenesis and as such males are rare and sexual breeding non-standard.[74] Females engage in sexual behavior to stimulate ovulation, with their behavior following their hormonal cycles; during low levels of estrogen, these (female) lizards engage in "masculine" sexual roles. Those animals with currently high estrogen levels assume "feminine" sexual roles.

Lizards that perform the courtship ritual have greater fertility than those kept in isolation due to an increase in hormones triggered by the sexual behaviors. So, even though asexual whiptail lizards populations lack males, sexual stimuli still increase reproductive success.

From an evolutionary standpoint, these females are passing their full genetic code to all of their offspring (rather than the 50% of genes that would be passed in sexual reproduction). Certain species of gecko also reproduce by parthenogenesis.[75]

this paragraph was taken from the wikipedia article found here:
http://en.wikipedia.org/wiki/Homosexual_behavior_in_animals

That's interesting, I'd always assumed that homosexual behaviour had something to do with the social and also perhaps maternal tendencies of mammals, and that it would be less frequent, if at all found in reptiles.

 

[Andiferous]

To the best of my understanding, the function of sex and its role in general becomes broader and more political in more complex societies - or at least as I have learned within primate cultures. So I suppose we could guess that the psychological role of sex may increase in proportion to higher thinking abilities and complex social orders.

To my limited understanding there is no difference in physical drive between mammals, but I've no evidence on hand to back that up. They have found an obvious correlation between hormones and pheromones and sexual attraction; I seem to remember a study in which testosterone smears on either sex sometimes repulsed male chimps, estrogen smears on either likewise attracted some regardless of sex. There is a biological thing but as thinking creatures, I don't think we're driven by instinct or biological imperative alone...

To assume so would have really awful moral implications.

 

[iamthedinger]

To the best of my understanding, the function of sex and its role in general becomes broader and more political in more complex societies - or at least as I have learned within primate cultures. So I suppose we could guess that the psychological role of sex may increase in proportion to higher thinking abilities and complex social orders.

To my limited understanding there is no difference in physical drive between mammals, but I've no evidence on hand to back that up. They have found an obvious correlation between hormones and pheromones and sexual attraction; I seem to remember a study in which testosterone smears on either sex sometimes repulsed male chimps, estrogen smears on either likewise attracted some regardless of sex. There is a biological thing but as thinking creatures, I don't think we're driven by instinct or biological imperative alone...

To assume so would have really awful moral implications.

i absolutely agree that in humans, environment would play a large role in sexual preference. the article that was referred to in earlier posts shows a 60% greater impact from environment over biological sources. there may be an increase within complex societies but studies have shown that humans are not the only animal that have shown homosexual behaviour.

 

[Andiferous]

To the best of my understanding, the function of sex and its role in general becomes broader and more political in more complex societies - or at least as I have learned within primate cultures. So I suppose we could guess that the psychological role of sex may increase in proportion to higher thinking abilities and complex social orders.

To my limited understanding there is no difference in physical drive between mammals, but I've no evidence on hand to back that up. They have found an obvious correlation between hormones and pheromones and sexual attraction; I seem to remember a study in which testosterone smears on either sex sometimes repulsed male chimps, estrogen smears on either likewise attracted some regardless of sex. There is a biological thing but as thinking creatures, I don't think we're driven by instinct or biological imperative alone...

To assume so would have really awful moral implications.

i absolutely agree that in humans, environment would play a large role in sexual preference. the article that was referred to in earlier posts shows a 60% greater impact from environment over biological sources. there may be an increase within complex societies but studies have shown that humans are not the only animal that have shown homosexual behaviour.

I can't see any way to use scientific methology to create a statistic here, especially about the effects of environment, though I agree the both probably affect sexuality. Also, I can't see an easy way to simplify sexual desire and such; it's certainly not darwinian. That's almost to say weak females are raped by strong males and we go without medical intervention, and I think we're pretty much past that. Additionally, I guarantee in most cases men and women have a different stimulus and motivation on this, and this varies even between various members of either group. There is no easy statistic imo.

 

[iamthedinger]

I can't see any way to use scientific methology to create a statistic here, especially about the effects of environment, though I agree the both probably affect sexuality. Also, I can't see an easy way to simplify sexual desire and such; it's certainly not darwinian. That's almost to say weak females are raped by strong males and we go without medical intervention, and I think we're pretty much past that. Additionally, I guarantee in most cases men and women have a different stimulus and motivation on this, and this varies even between various members of either group. There is no easy statistic imo.

the statistics that are shown here http://en.wikipedia.org/wiki/Biology_an ... rientation are from studies involving twins. the statistical data is generated from these studies

 

[Sparky]

natural selection, the process in which favorable traits are passed on to future generations. down syndrome, a defect where a child is born with an extra chromosome, number 21 i believe, would be pretty difficult to pass on. if you know someone with down syndrome you may find that they don't function on the same social level as people that were not born with the disease. they may not have any type of understanding of reproduction, depending on how severely they're effected. they may have sexual urges that they do not understand and i'm sure that in today's society, if they are biologically able to reproduce, it just might happen. before modern understanding of disorders, people with down syndrome would simply be branded as retarded and would either be destroyed or ostricized from normal society. either way, their chances of passing on any type of genes is pretty slim.
when people think of homosexuality, i don't know if they feel that this is only a human occurance. i can safely assume that it is not. it may not always be a choice made by the individual. like my reference to having seen a gay dog...it happens in nature. not just to humans. why would i point out how a possible mutation in a gene that would control individual attraction to other members of the same species apply to natural selection? i don't know, maybe i was just trying to point out the validity of the argument of what could possibly be a mutation that i obviously stated that i have done no personal research on and had just formulated the thoughts based on what i know about basic life functions.

i actually find it kind of insulting that you would try to compare homosexuality and down syndrome in how they would relate to natural selection.

two members of the same sex find each other attractive, they have no intention on conceiving a child with a member of the opposite sex, they don't pass on any of their genes to a future generation, whether there actually is a mutation or not. i'm just saying that if there is a mutation of a gene that controls attraction....well gosh they're less likely to pass that mutation on...and take into consideration that i'm not just talking about humans. humans are not the only species that are attracted to one another through chemical reactions from pheromones.

and thanks for the link...

First off: I didn't intend to be offensive in my comparison. I was just on the cusp of leaving for a lecture and was writing quickly and it was the frst thing to come to mind - this is also the reason I didn't check the Wiki page which I normally would do.

Also, I just realised how homosexuality could be selected for (to some extent).

If a couple (1st Gen) have a slight propensity to produce offspring who will not produce children themselves then their offspring (2nd Gen) who DO reproduce will possibly have some other 2nd Gen relatives (brother/sister equivalents) who could help out with food gathering or nuturing requirements, thus increasing the chance of the survival of the 3rd Gen offspring.

Thus it would be of benefit for couples to be able to produce some offspring who would not wish to reproduce in order to increase survival chances of their family further down the line.

Is this reasonable? I am not a biologist so there isn't a huge amount of weight behind my reasoning necessarily

 

[he_who_is_nobody]

The thing everyone seems to be forgetting is that we have sex because it is pleasurable. Producing offspring is a side effect. Granted, this probably was not always the case, but it seems that at least for most mammals, we have sex because we enjoy it. Offspring are an after thought. Of course, homosexual relationships are natural, just like masturbation, multiple partners, and heterosexual relationships.

I am not sure about orangutans, but all the African apes (chimpanzees, bonobos, and even gorillas) have been commonly documented in having homosexual relationships. Other primates have been seen to have homosexual relationships too.

To be perfectly honest, I think we are looking at this problem with our modern values (i.e. male/female pair bonding as the norm, when we are not sure that was the norm). There is a lot of evidence from modern hunter/gatherer societies that show male/female pair bonding is the most likely for our recent ancestors, but even within those studies, we find a lot of cheating on partners. Look at some ancient societies (e.g. Rome, Greece, etc"¦) we see many homosexual relationships and no real emphasis on virginity. Looking at other ancient societies (e.g. Hebrews and other Arab groups), we see bigamy and a large emphasis on virginity.

Therefore, the real question should be is male/female pair bonding for life (forsaking all others) natural? It seems rare in the animal kingdom and human history. Nevertheless, for some reason in western cultures we seem to think it is the norm.

If you ask me, humans are just like any other animal. We like to have sex, and if we can find someone else to have sex with, well all the better. However, asking a question about whether natural selection would select for homosexuality is the wrong question. The better question is why do we have these social constructs in the first place? Why did we create them and what purpose did it serve and might still be serving?

As for the question, would natural selection select for homosexual relationships? Well, as iamthedinger has already pointed out, it already has selected for it in the Whip-tailed Lizard (New Mexico's State Lizard) in a manner of speaking. Natural selection works on variation within a group, thus if the variation is already there (or comes about through a mutation), than deemed fit by nature, it will evolve as such. Moreover, you have to remember that there are nearly 7 billion people on earth right now, which is a lot of variation and possible mutations for natural selection to work with. Furthermore, trying to shoe horn 7 billion people into one archetype seems a little ridiculous to me.

 

[Giliell]

However, asking a question about whether natural selection would select for homosexuality is the wrong question.

As far as I know there is data that suggests that homosexuality is beneficial and thereby selected for under certain conditions (as well as for at least temporarily monogamous relationships).
The most important things to remember are that:

-evolution happens to populations, not individuals

-human reproduction is terribly fail-prone and dangerous

Let's start with that latter since that is the key. We're not rabbits who can afford to lose more than 90% of one year's offspring during that year. Rabbit pregnancy and birth seem to be rather uncomplicated, so a doe can always poop out some more . Human pregnancy is dangerous, exhausting and does take a lot of time. If you live in a cave and start reproducing at 15 and have a kid every year (which is quite unlikely), you probably make it to 10 before you die. If 90% die before they reproduce themselves, your population dies out. If the mother dies after 3, even worse. So you have to make sure that a lot of the pregnancies are successful and the kids make it to adulthood.

Sure , you live in a tribe who basically cares for you and the children, but if there's a man who walks the extra mile to make sure that you and the kids are ok and well-fed, you've got an advantage. It's not only beneficial for the mother, but in terms of evolution also for the father because his offspring has a better chance of survival. Just like in modern times: whose kids will be more successful: those of a single parent on welfare or those from a family with a principal bread-winner (not supporting patriarchy here, just making an analogy)?

I think this sense of "duty towards your wife and kids" is deeply engraved into our minds, much beyond the levels of culture and religion.
Imagine the following news items:

A) Harold, a DINK has left his wife
B) Harold has left his wife and his two teen-age kids
C) Harold has left his wife who's 8months along and the toddler.
I think that even people who have no problem with A and little problem with B would have an intuitive reaction to C.

Now back to homosexuality and our little tribe in the cave. As pointed out before, the human way of reproduction is not the rabbit way. So having adults who don't reproduce themselves (much, I think we can agree that in a society where homosexuality is not stigmatized and reproduction happens the good old-fashioned way, homosexuals will always reproduce less than heterosexuals) but help you with raising your offspring because they're your brother/sister is indeed beneficial. Also in case of the untimely but not unlikely death of the parents, the kids are most likely better off with gay uncle Ugh than with proud-father-of-five uncle Agh.

Still much of this is being disputred, but it is a hypothesis why homosexuality might be selected for.

 

[Squawk]

If we are to conclude that homosexuality is entirely genetic/developmental in nature (rather than influenced by environment on a learning level, which I happen to suspect is true), then we can posit numerous selection pressures that would result in the propogation of "gay genes", as it were.

To explore these options properly we would need to set aside any prejudice in society and consider our evolutionary history. You'd then look at social factors, enhanced relationship within groups for example. Attraction is easy to understand from an evolutionary stand point. Consider bisexuality as a bond forming tool, and then consider various degrees of bisexuality, with the two ends of the scale being 100% homosexual and 100% heterosexual.

Alternatively, consider a positive impact on the offspring of a given female if 1 in every 5 of her children (for arguments sake) does not pro-create. How would this impact in times of hardship, for example?

So many ideas, too hard to pin down, but extremely easy to show how homosexuality arises and remains in a population. I'd suggest a study on our closest relatives (all other apes) would be the best place to start.

 

[Giliell]

If we are to conclude that homosexuality is entirely genetic/developmental in nature (rather than influenced by environment on a learning level, which I happen to suspect is true), then we can posit numerous selection pressures that would result in the propogation of "gay genes", as it were.

AFAIK, there are several identified factors for male homosexuality (lesbians seem to be of no interest)
One for example is the amount of older brothers by the same mother regardless of whether the boy grows up with them or not. The more male pregnancies a woman had, the stronger is her imune reaction to another male pregnancy and she also release more "female" hormones. Hormone absorption in the womb at a critical point of pregnancy seems to play a huge role, but this may have to do with actual gene expression.

 

[Squawk]

AFAIK, there are several identified factors for male homosexuality (lesbians seem to be of no interest)
One for example is the amount of older brothers by the same mother regardless of whether the boy grows up with them or not. The more male pregnancies a woman had, the stronger is her immune reaction to another male pregnancy and she also release more "female" hormones. Hormone absorption in the womb at a critical point of pregnancy seems to play a huge role, but this may have to do with actual gene expression.

It's entirely gene expression, a gene has no influence if it is never expressed. We can be safe in the assumption that the genetics of the egg are no different from the eggs of previous kids given the nature of egg production (unless someone has more info on female meiosis than I do) so expression is the only candidate. Understanding why this is the case, however, is crucial. Does the female body supply hormones/provide an environment "designed" to produce homosexuals because it has evolved to do so, or could it be damage from previous pregnancies? Is it age related?

Last time I checked this was still at the hypothetical stage, though I may be out of date.

 

[Independent Vision]

1. Women are more important than men, biologically. Men can impregnate several women in the span of one day if he so pleases. Women can only be impregnated by a maximum (not counting modern technology) of two men in the same year.

2. There is a hypothetical reason for homosexuality. I think it's called "The Benevolent Uncle". Meaning that having individuals who does not procreate themselves will ease up positions in society for these to be caretakers with no special need for the furthering of their own genetics.

Personally, I don't think it's as simple as "a gay gene". I honestly don't think homo or hetero exists as such. But that's just my theory. I think our gender preferences can always be swayed depending on what we are focusing on.

There are also other things to consider. Men have been "closet homosexuals" for quite some time, same with a lot of women. Where they have gotten married, had kids but were never really satisfied with th relationship. If they have sex, we can assume that sex with someone different from your own sexual preference is very possible, and I don't think a lot of these kids would turn out homosexual just because their parents were.

So this means that, as a lot of other things, there is a difference between sex for procreation and sex for pleasure. There's also a difference between relationship for sexual intimacy and relationships for emotional intimacy as well as for intellectual intimacy.
Some people, such as me, are lucky to find a partner who can provide all three at the same time. I also have other relationships for intellectual and emotional intimacy, but I only engage in sexual intimacy with my husband. Since we use birth control, we are currently not having sex to procreate.
My sister recently had a child, which has actually put a chill pill onto my "biological clock" so to speak.

I am, what I classify as consensual-human-adult-sexual. Sure, I've primarily focused on men as a source of sexual intimacy, but have enjoyed the company of other women as well.
I think we've developed a very "this or that" way of thinking about relationships. The concept that your significant other is supposed to satisfy all your needs on all levels... emotional, intellectual, sexual, security wise... is probably something that is we can blame the more unforgiving world religions for.

I don't think it's anything special in our genetics, nor do I think that heterosexuality is ingrained in our genetics. There are plenty of other animals that have sex for pleasure and who have instances of homosexuality.

Bruce Bagemihl is a Canadian biologist who has done studies and reviews that seem to indicate DOCUMENTED instances of sexual behavior for non-reproduction purposes in over 300 different animals species.
They include mammals, birds, reptiles and even insects... (Yeah, I know wikipedia is so-and-so, but anyway):
http://en.wikipedia.org/wiki/Homosexual_behavior_in_animals

Black swans have an estimated homosexual population of one quarter. They pair up, steal a nest and drives the female away. More of these kidnapped eggs survive to adulthood than that of a hetero pairing.

The Amazon Dolphin is reported to have group sex.

The American Bison has been documented to have full fledged male homosexual pairings in the shape of courtship, mounting and full anal penetration. And the mounting of one female of another is common in cattle.

Bonobo's are bisexual as a norm. And over 60% of their sexual behavior is between two or more females.

Elephants form same sexed couplings quite often, with both affection, companionship and sex. Especially among males, and then usually an older and a younger male.

In one study regarding giraffes up to 94% of observed mounting was conducted between two males.

Dragonflies seem to engage in homosexual couplings.

Male bedbugs will mate with any other bug that has recently fed, male and female alike.

So... sexual behavior which is not strictly reproduction driven is quite normal. Especially in mammals who are considered more intelligent, like Bonobo, Elephants, Dolphins... yeah.

Where was I going with this? Oh, yeah. I think the reason we feel we "need" to be either or is because of social stigmata. Homosexuality has been reported in all great apes and a great deal of primates, so it's not as though humans are special and homosexuality is "against nature". If it was a bad thing, in terms of natural selection reason would suggest that it wouldn't be so common, wouldn't it?

But, as I said, with humans I think it's a lot like with Bonobos and Elephants. Bisexuality is probably the norm, once one gets rid of the stigma left by religion and upbringing.

Wall of text. Sorry about that.

 

[iamthedinger]

the main subject of my initial post was to seek more insight into the possibility of genetics playing a role in sexuality. i do understand that there are many other contributing factors and it can't simply be genetics, but i think there is a possibility that a predisposition to attraction of pheromones produced by the same sex may be a factor. as for posting wiki links...i think the last link in particular has already been referred to in this topic about 3 or 4 times.

 

[Giliell]

AKAIK the role of pheromones in humans is highly disputed.

Does the female body supply hormones/provide an environment "designed" to produce homosexuals because it has evolved to do so, or could it be damage from previous pregnancies? Is it age related?

That's the big question. I don't think whether it's about "designed" but about "selected". It clearly is no automatism, there are families where son #6 is as straight as #1 and others where the firstborn is gay. So, would it be an advantage if after a certain number of male pregnancies there comes the benevolent uncle? (I'm highly in favour of benevolent uncles, I hope my BIL makes a lot of money one day )