Most people nowadays believe that being gay is genetic. If this is indeed true, given the fact that homosexuals do not reproduce near as much as heterosexuals, why have their numbers not dwindled?
Just because it’s genetic doesn’t mean it’s heritable, and thus subject to selection. It could be a random mutation that is relatively common (like, for example, Marfan Syndrome, in which approximately 25% of the cases are the result of spontaneous mutations, rather than inherited ones). It could also be the result of hormonal interactions which could be triggered by certain parental genetic combinations.
And, I believe it is largel considered to be biological in origin, but not necessarily genetic, or, at least, not entirely so.
As Darwin’s Finch mentioned I do not think it is an inherited trait.
I am certainly no expert but my understanding is that your sex selection is not as black & white as you might think. Just getting an XY or XX chromosome pairing does not throw you completely into one sex or the other. There is more to it and a gray area exists.
Certainly there have been homosexuals throughout recorded history (and I am willing to bet before that too). That in itself should argue that there is more to it than natural selection in play else the OP would be correct.
I am unaware that anyone has definitively pointed out how homosexuality is a biological condition. It may well be…or not. I do not think anyone can really say although from knowing homosexual friends and family I tend to agree that it is not a “choice” of theirs. Indeed most have opined that if it was merely a choice they’d have opted for heterosexual (considering the hell they went through coming out of the closet…few young people would “choose” that). They see it as not a choice but a fact of life.
It’s because in reality it’s a choice they make… to paraphrase david cross…every gay kid sits in their room one day and says:
nobody likes me at school…
and I really have a hard time fitting in…
I’m just so awkward…
and I have no friends…
but you know?
Maybe there’s something else I can do to invite criticism in my life?
Just kidding…I just got the feeling that Fireclown was some kind of troll, but upon checking his post history he seems ok. But anyway, I love David Cross’s take on it, because I’d imagine that a lot of gay folks realize that they’re gay during their most awkward years. Years where you’d prefer the least amount of drama possible. It just shows how silly the assertion can be.
“My mother made me a homosexual!”
“If I gave her the yarn, could she make me one too?”
Actually, this statement isn’t completely true, according to my understanding.
There have been people throughout history who have shown homosexual behaviors. But pidgeonholing individuals as “homosexuals” is a convention invented in the last hundred years or so.* This is, in my eyes, the problem with the occasional historian trying to make a name for himself who claims proof that such-and-such a famous historical figure (Shakespeare, Julius Caesar, Elizabeth I, what have you) was gay. Even if Shakespeare did enjoy sex with other men (not saying he did), he never would have thought of himself as “a homosexual.” There was no such concept.
So relating this back to the OP: if homosexuality were genetic (and the consensus in this thread seems to suggest otherwise so far), then there’s no reason it couldn’t be passed down through history like any other genetic trait. These genes would stop being passed down only when society changes its expectations of those it has labeled “homosexual” to exclude any heterosexual conduct whatsoever. It’s a bit scary to think that, to some extent, this is exactly what has happened (in Western culture) in the past 50-75 years.
*I am not a sociologist. My understanding of this issue comes from a few articles I read as an undergrad. If a real historian/sociologist/queer theory person wants to come and correct me, I’m all ears.
That’s similar to my first thought on reading the OP as well. Perhaps up to now, there has been strong societal pressure for a man to get married and have children regardless of whether he was what we now classify as “gay”. But nowadays he need never speak to a woman at all, if he so wishes.
For example, I doubt that Oscar Wilde would gotten married and had a son in today’s world. Which means he never would have passed on his genetic material.
So maybe it’s society’s condemnation or ignorance of homosexuality that actually kept a “gay gene” in play all these centures? And now that the condemnation/ignorance is disappearing . . . ?
OTOH, the jocks and cheerleaders are going to torment and disdain me no matter what I do, so I might as well join some people I can get along with in the band / the choir / the sk8ters / the Latin club / the gays . . . ?
This might be crazy, but the case of sickle cell anemia is a good example of how certain traits don’t “become extinct.”
As I recall, getting one of the sickle-cell genes makes you a LOT more resistant to malaria, but getting two copies, one from each parent, leads to a much higher risk of heart attack, stroke, or other blood clotting problems. Not saying that homosexuality has such a simple genetic basis, but there could be something of the same sort happening on some level.
Indeed. My Dad’s gay and has four children. None of them are gay. However my older brother, who shares no genes with my Dad, is following the same path in life as Dad did and I’m sure he’ll ‘come out’ sooner or later. He was raised from a young age by Dad though.
So my personal experiences with Homosexuality suggest to me that it’s not genetic, but psychological. But that doesn’t make it a choice, when so much of everyone’s psychological makeup is not by choice.
Am I aware of course that my personal experience proves nothing, and there’s always more to the explanation than we’re aware of.
So, to sum up, no danger of lesbians becoming extinct?
Interesting question–among homosexuals who do start families, I had the impression (from popular media, I guess) that lesbians opt for artificial insemination and carry their own natural children, whereas gay men generally adopt rather than look for a surrogate mother.
I know it’s the fashion to say that “a homosexual” is only a modern concept, and that before the late-19th or 20th century homosexuality was only thought of as a type of sexual activity, not as a type of person, blah, blah, blah — I think that is utter crap. We have every reason to believe that, just as today, most people in Shakespeare’s day had fixed sexual orientations that were not of their choosing. Shakespeare, being in the theater, could not have been unaware of certain men who had no sexual interest in women and seemed to fancy their own gender — and that this was not some temporary mood, but a lifelong characteristic (viz., the title character in The Merchant of Venice). Such men weren’t called homosexuals, no, they were probably called things like sodomites, and no, there was no group identity as there is today, in the political sense.
Maybe the gene doesn’t make one attracted to one’s own gender. Maybe the gene makes one desire *men *more. Then it might be passed down even *more *by women. To simplify what I’m saying, men might become attracted to men and thus be gay, women would be more attracted to men and become “sluts.”
(Note that I’m not saying that this is how it works, I’m just suggesting an alternative explanation.)
Same reason lefthanders aren’t becoming extinct, either.
Ummm…correct me if I’m wrong, but most gay people have straight parents, no?
Since people keep having babies and their babies keep turning out both gay and straight, I don’t think we’re ever going to live in a totally gay or straight world.
That, to my mind, is a good thing.
Because people keep breeding
This is a good way to put it, but if homosexuality were genetic, the basic paradox still stands. If some number of your offspring don’t have offspring themselves, from a purely evolutionary point of view they’re dead ends and will reduce the effective number of your offspring. If a genetic trait causes this a significant portion of the time then it should, over time, be weeded out.
But from what I can see of the research being done currently, there’s a trend toward thinking that homosexuality is inborn but not genetic. There’s evidence that it’s strongly influenced by conditions in the womb. But whatever this condition is, as long as it occurs evenly among populations it won’t be strongly selected against so long as the overall race is being successful (which humans certainly have been). This goes back to irishgirl’s point.
One might still say that, for the human race as a whole, there should have been some evolutionary pressure to dispose of this developmental mechanism (particularly over the eons where we, and our ancestors, weren’t dominant.) But to really answer this we’ll need to know more about what the mechanism is and how it interacts with other processes. Indeed, it may turn out that there’s some evolutionary benefit to having a certain percentage of homosexuals in the population (something like the “Grandma effect”.)
Also, please consider that evolutionary pressures favor those who have the most grandchildren, not the most children. Suppose (and this is totally hypothetical, by the way) a set of parents have four children, one of whom has no sex drive at all. Three of the children go on to have four children each, while the fourth does not, but may contribute to the welfare of its nieces/nephews in a significant way. So in that case 12 grandchildren are supported by 4 children, rather than 16 grandchildren. But the difference between 1/3 of an adult’s production and 1/4 of an adult’s production may be quite significant, and more of those 12 grandchildren will survive to have their own kids and grandkids.
eta: like the ‘grandma effect’ mentioned above
Indeed, see the book *Evolution’s Rainbow: Diversity, Gender, and Sexuality in Nature and People* by Joan Roughgarden.