Is homosexuality genetic?

[Tatyana]

I have -- and it actually supports Speed of Light's point.

Ancient Greeks actively condoned homosexual behavior, but took rather dim view of exclusive homosexuality. Actually having children was considered very important. Same with Romans, Persians and for that matter Chinese -- Confucius had nothing against what men do for their own pleasure, but considered marrying and having children a duty to the state.

I am not aware of any pre-modern culture which was okay with gays being JUST gays.

Speed of Light was suggesting that the prevalence of homosexuality was a modern phenomena.

I think you just proved my point.

 

[Mark6]

Speed of Light was suggesting that the prevalence of homosexuality was a modern phenomena.

I think you just proved my point.

Speed of Light, can you clarify what exactly you meant?

I read your post #16 as unconstrained expession (not prevalence) of homosexuality is a modern phenomenon, and that for the first time in history gays are free NOT to engage in hetero sex -- and thus not reproduce. Which is not the same as "free to engage in homo sex" -- that happened many times.

 

[ponderingturtle]

Speed of Light, can you clarify what exactly you meant?

I read your post #16 as unconstrained expession (not prevalence) of homosexuality is a modern phenomenon, and that for the first time in history gays are free NOT to engage in hetero sex -- and thus not reproduce. Which is not the same as "free to engage in homo sex" -- that happened many times.

I am not sure that it entirely true, there are some examples of homosexuals being given non reproductive religious roles in some societies.

 

[HansMustermann]

TBH, though, it seems to me like

A) those greeks too had plenty of loopholes, if they wanted to show the community they have children. Just marry a hetaera for example. Or the woman was the man's property to such an extent, and wasn't even allowed to testify in a court or anything, that you could basically delegate screwing your wife to someone else. Neaira for example was literally used in a settlement between her husband and another guy in a, basically, "and you can screw my wife too" clause.

Not saying that everyone would do that or anything. I mean, heck, even in modern days enough gays or lesbians eventually want children of their own, so I'd imagine the greeks too would eventually get around to screwing the wife too. But, technically, if one felt that strong about being exclusively gay, it's not like they couldn't game the system.

B) it seems to me like much of this kind of stuff, well, it's not like it would end up prosecuted or anything, unless you were already a hated enough jerk and they were itching for some reason to string you up already.

E.g., while technically it was forbidden to keep a gay lover past the age where they got a beard and hair on their legs (yep, they were pedophiles), it seems that the practice of just shaving them was pretty widespread. And if it ever came to being hit by the law for it, it would be the boy who gets punished, not the older guy who kept him past the prescribed age. And even then only if they were a citizen, and it seems only if someone really needed a reason for some legal jiu-jitsu.

E.g., Timarkhos was a known such guy who kept being the passive one in gay relationships for a long time, but he wasn't actually sued for it until he tried to sue Aeschines, and Aeschines counter-sued to strip him of his citizenship, and thus prevent him from suing a citizen like Aeschines. Had he not made that step, he could have kept at it without anyone actually minding. And even then, Aeschines seems to have had to make the case that Timarkhos had been the lover of more than one guy, and thus had too low morals to be a citizen. It's not hard to extrapolate that if Timarkhos had stayed with just his original protector, he wouldn't have been sued. And I mean as in: in fact, leaving that original protector was the root accusation against him in the first place.

But maybe even more importantly, it was possible because Timarkhos was a citizen. If some guy chose to have a slave lover or just stick to male prostitutes, there was no law against that for either of them.

So basically technically some communities might have taken a dimmer view of people who aren't doing the gay thing right but it seems to me like you had to make an enemy or two for that to actually matter at all.

 

[Tatyana]

It's only really in the last generation or two, that those with a potential (weakness?) have been encouraged (allowed?) to express their homosexuality.

So evolution has not yet had a chance to eliminate this trait.

It might be that in a very few generations, homosexuality will be drastically reduced

This the post in question.

I used the word prevalence, which wasn't correct.



However, I still assert that your post proved my point, that it isn't a modern phenomena that homosexuality has been expressed in society.

I also request you clarify the meaning of (weakness?)

 

[Drewbot]

This is inherent biological wiring, and so imply that people who are gay can overcome their 'conditioning' (unless you mean something like feelings of guilt), smacks of the religious right trying to 'cure gay homosexuals'.

Are you saying in ALL cases, it is inherently biological? or are there some cases, where it is simply a choice, or the result of an environmental condition?

 

[casebro]

I am fairly positive I can provide far more evidence for the genetic basis of sexual orientation and the lack of free will....

Please display some evidence.

This is inherent biological wiring, and so imply that people who are gay can overcome their 'conditioning' (unless you mean something like feelings of guilt), smacks of the religious right trying to 'cure gay homosexuals'.

Strike the word "biological", replace it with "conditioned"and you may be saying something important. Basically, whether the tendency is genetic or experience based, some things are just too deeply ingrained to 'cure'.

Personally, I don't care where somebody else gets their affection, or how they get their rocks off. But there are some things not polite to discuss in public. I was happier when the gays were still in the closet. Unfair? Yes. But I do have a right to my own personal opinion.

 

[Tatyana]

Are you saying in ALL cases, it is inherently biological? or are there some cases, where it is simply a choice, or the result of an environmental condition?

I would assert that it is biological.

Is your sexual preferences a result of conditioning or the environment you grew up in?

 

[Tatyana]

Please display some evidence.



Strike the word "biological", replace it with "conditioned"and you may be saying something important. Basically, whether the tendency is genetic or experience based, some things are just too deeply ingrained to 'cure'.

Personally, I don't care where somebody else gets their affection, or how they get their rocks off. But there are some things not polite to discuss in public. I was happier when the gays were still in the closet. Unfair? Yes. But I do have a right to my own personal opinion.

Yes, but not your own facts.

I find it offensive when people think that they can 'cure' homosexuality, or that they think it is weakness or pathology.


It doesn't make any sense at all, as it is pretty evident from the frequency of humans born who are intersex, reproductive strategies, sexual expression, in the entire animal kingdom that there are not these rigid opposites.


I think the most compelling evidence that it is biological is that there are differences in male and female brains, and that these differences are the result of the sex steroid hormones that the foetus is exposed to in utero.

A brief summary of all the evidence:
http://www.stanford.edu/dept/news/pr/95/950310Arc5328.html

Homosexuality is biological, suggests gay sheep study
http://www.newscientist.com/article/dn3008-homosexuality-is-biological-suggests-gay-sheep-study.html

There were two major differences found in the brain scans if I remember correctly.

Symmetry Of Homosexual Brain Resembles That Of Opposite Sex, Swedish Study Finds

http://www.sciencedaily.com/releases/2008/06/080617151845.htm

Gay brains structured like those of the opposite sex
http://www.newscientist.com/article...tructured-like-those-of-the-opposite-sex.html


While looking for the brain scan articles I came across this:

Evolution myths: Natural selection cannot explain homosexuality

There are numerous evolutionary mechanisms that might explain homosexual behaviour, which is common in many species of animals

"Simple reasoning shows that evolution cannot explain homosexuality - how would a homosexuality gene get selected for?" "Why have the genetic traits predisposing to homosexuality not been eliminated long ago?"

Such arguments are surprisingly common - and completely wrong.

Read on..........

http://www.newscientist.com/article...l-selection-cannot-explain-homosexuality.html

 

[Drewbot]

Is your sexual preferences a result of conditioning or the environment you grew up in?

I wouldn't know. I can't say what other people's sexual pref. would be, if they grew up in the same environment as I did. If sexuality is purely biological, however, would the environmental conditions matter?

 

[Drewbot]

"Simple reasoning shows that evolution cannot explain homosexuality - how would a homosexuality gene get selected for?" "Why have the genetic traits predisposing to homosexuality not been eliminated long ago?"

Such arguments are surprisingly common - and completely wrong.

They start the article saying that the arguments are wrong, and then say this:

It is still not clear to what extent homosexuality in humans or other animals is genetic

So is the argument really wrong?

 

[Mirrorglass]

They start the article saying that the arguments are wrong, and then say this:



So is the argument really wrong?

What the article attempts to disprove is the argument "homosexuality cannot get selected". That, in my opinion, it does quite well. The fact that we don't really know whether or not homosexuality has been selected is irrelevant.

 

[Tatyana]

They start the article saying that the arguments are wrong, and then say this:



So is the argument really wrong?

No.

It is only wrong if you use half the sentence out of context.


Homosexual behaviour has been observed in hundreds of species, from bison to penguins. It is still not clear to what extent homosexuality in humans or other animals is genetic (rather than, say, due to hormonal extremes during embryonic development), but there are many mechanisms that could explain why gene variants linked to homosexuality are maintained in a population.

 

[joe911]

This has nothing to do with counselling or 'conditioning'.

This.

“I grew up with heterosexual teachers, parents and siblings, in a culture that is fiercely heterosexual and why am I not a heterosexual. No disrespect intended, but if teachers had that much influence on students, there would be a lot more nuns running around!”~Harvey Milk

When I grew up I was lead to beleive that "Boys who dont like football are gay and girls who are into 'boys stuff' are probably lesbians" among other stereotypes such as gay men like to dress in womens clothes and spend all their time clubbing and having sex. If the conditioning theory were true,when I discovered my homosexuality I would have automatically indulged in those things as it would be in my 'conditioning' that that would be my role as a homosexual.

During 168 hours of BBC programming, gay life was positively and realistically depicted for just six minutes.Source

 

[HansMustermann]

They start the article saying that the arguments are wrong, and then say this:



So is the argument really wrong?

Not really, the way I see it. If an argument having X as a conclusion is wrong, doesn't mean that X is then false. It means that the argument failed to support or disprove X either way. Unless other inferrences and data nail it, basically you don't know.

Plus, as was mentioned before, genetic diseases don't have to be selected for. Most are badly repaired DNA breaks that are actually as recent as that particular individual. So those arguments would fail to disprove the "fabulous gene" (I like that name) anyway.

Additionally, statement of the form basically "no X is Y" (e.g., basically the thrust there was "no homosexuality is genetic") does not negate to "all X are Y", but basically to "some X are Y." Mind you, it's not very relevant after the first paragraph above, but essentiall just saying that it's not an all or nothing situation anyway. Even if there were a "fabulous gene" after all, it's not necessary that all cases would be 100% due to it. It's possible that some other factors would cause or contribute to that brain wiring like the opposite sex.

Basically, in the absence of any other information, basically "we don't know how much" seems to me like the honest thing to say.

 

[John Jones]

It's only really in the last generation or two, that those with a potential (weakness?) have been encouraged (allowed?) to express their homosexuality.

...

Is that true across all cultures?

 

[Speed of Light]

Speed of Light, can you clarify what exactly you meant?

I read your post #16 as unconstrained expession (not prevalence) of homosexuality is a modern phenomenon, and that for the first time in history gays are free NOT to engage in hetero sex -- and thus not reproduce. Which is not the same as "free to engage in homo sex" -- that happened many times.

Yes. That sounds about right!
I'm not an expert on what happened in the past, but the stigma has now been removed from a homosexual lifestyle.
My feeling, based on knowledge of evolution, and looking at it logically, was that, because the change has been so drastic so quickly, and because the mood in the countries has been (artificially) altered deliberately by the media e.g. by campaigning, the trait would diminish considerably very quickly - in a few generations, providing that the conditions in the country(s) remain unchanged.

It's partly because of the unconstrained expression, as you say, but I also think that the rapidity and the artificiality of the way the change has been brought about, is a very relevant factor.
My feeling is that, in the long run, a price must be paid for any change as drastic as this - and I'm not convinced that the media has been able to do this in past times.
Evolution usually takes a long time to change things, but that is because it responds to slight environmental changes over time - but in this case, the environmental change has been a massive shift, so my feeling is that any evolutionary change will happen relatively rapidly.
I might be wrong, but I would be willing to bet on it!

 

[Speed of Light]

It's only really in the last generation or two, that those with a potential (weakness?) have been encouraged (allowed?) to express their homosexuality.

So evolution has not yet had a chance to eliminate this trait.

It might be that in a very few generations, homosexuality will be drastically reduced

I also request you clarify the meaning of (weakness?)

For the purposes of this debate, I did not wish to make a value judgement on whether homosexuality was right or wrong. I was interested only in analysing things logically from as neutral perspective as possible.

My solution to the neutrality issue, was simply to give both perspectives at once.

Often, I find it hard to express neutrality by just one word, so I use two words to illustrate that there are two opposite points of view.
For example, the moden point of view portrayed by the media, is to simply see homosexuality as a potential, and enlarging 'normality' to encompass it. However, there are also many people, often older people, who think that, at least in some cases, the individual has been exposed to environmental influences, which have created an unnatural state - In this case, the individual might be more easily influenced than someone else, and so might be described as having a 'weakness' in this area.
Weakness, in this case, would be defined as the opposite of internal strength, and simply means a bit more susceptible to environmental influences.
In an effort not to join the debate regarding this, and to remain neutral, I described homosexuality as merely a potential, but, aware of another, and opposite perspective of it, and wanting to create the 'feel' of seeing the two perspectives at once, without coming down on either side, I put 'weakness' in brackets, so as to also draw attention to that idea.
So I felt that saying 'those with a potential (weakness?)' was as neutral as I could get, acknowledging the two sides in the debate, but not coming down on either side. Seeing it from as much of a 'bird's eye view' as possible.

I find it offensive when people think that they can 'cure' homosexuality, or that they think it is weakness or pathology.

Becoming offended by others' ideas, is not a constructive way of having an open minded discussion.
In my opinion, reflecting from all sides, is a prerequisite to having a constructive interaction.
There are many people who grow out of, or are 'cured' of their homosexuality, as they get older. Do you feel offended by this?
Do you wish them to remain as homosexuals, even though this might be an unnatural state for them??

 

[Roboramma]

Basically, evolution doesn't always favour only those attributes that promote the survival of the individual, but also those that promote the survival of the entire community. This is called kin selection^WP. It is known that animals exhibit altruism, behaviors which don't necessarily result in passing on of genes, but improve the overall fitness of the group. The idea is fairly simple; from an evolutionary point of view, your brother or even your second cousin surviving means many of your genes will pass on, so behaviours that promote their survival are often favoured by natural selection.

I agree that kin selection works, and is an important part of natural selection, but your description here seems to mix it up with group selection. And while group selection can occur in some special circumstances, it's very hard to get that mathematics to work out, especially when the trait in question is selected against on an individual level.

To be clear: it's not that traits that are beneficial to the larger group are selected for, it's that traits that are beneficial to kin are selected for.
And to understand how that happens, I prefer the idea of gene level selection: genes for traits that cause those genes to proliferate (whether due to the reproduction of the individual whose genes cause that trait, or the reproduction of others who carry that gene) are selected for.

So how does this relate to homosexuality? Well, basically, humans are extremely social animals. It is our capability for forming large and complicated societies that has allowed us to become the dominant mammal on the planet. But as I'm sure you've noticed, it takes a lot of work to maintain social relationships. Every day, we smile at each, exchange pleasantries, look each other in the eye.. a lot of things that aren't strictly necessary for survival, but help hold the society together.

Those things are all easily explained by individual level selection, though, without even kin selection: we survive in a social environment, and our relationships with others effect our ability to survive and reproduce. Adapting to that environment doesn't require any special explanations.

So, to sum it up, it's possible that homosexuality serves a social function that improves the overall fitness of the human race.

That's group selection, and it doesn't work. Or, more clearly, it can't explain traits that are selected against on an individual basis, because the individual level selection would swamp that group level selection.
Note that group selection is different from kin selection, which does work and explains a great number of things in the natural world.

There is no "overall fitness of the human race".

None of what I'm saying suggests that homosexuality is not selected for, mind you: there are plenty of ways that it could be selected for. Kin selection, which you mentioned, is one: homosexuality might lead to having, on average, fewer children, but more nieces and nephews, in the same way that sterility in ants leads to more nieces and nephews (the ants in a new colony are the nieces and nephews of the sterile workers in this one). And since the genes for homosexuality are likely shared by me and my (reproducing) brothers and sisters, they get passed on.

There are plenty of other possibilities, but I don't think group selection is one of them.

 

[Roboramma]

Not quite. Natural Selection is not the entirety of evolution. Consider: Down's Syndrome and sickle-cell anemia both have notably deleterious effects, yet they persist. Why? Because our genetic code is subject to damage, replication error, and other forms of mutation. Particularly where the selective pressure against a particular trait is small, the incidence of that trait brought on by novel mutation may well exceed any possible decrease in reproductive rates exhibited by individuals who possess that trait.

Just a minor detail, because I like your post, but sickle-cell anemia is selected for. Of course it's also selected against. It's an example of frequency dependent selection