On the causes of sexual orientation

http://www.sciencedaily.com/...ases/2008/06/080617204459.htmThis article refers to several facts about homosexuality and genetics such as twin studies etc.It then discusses population modeling to pick between various hypotheses about why some homosexuality may remain in populations.

quote:

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An unexpected implication of the new models concerns the impact that the sexually antagonistic genetic factors for male homosexuality have on the overall fecundity of a population. The findings suggest that the proportion of male homosexuals may signal a corresponding proportion of females with higher fecundity. Consequently, these factors always contribute, all else being equal, a positive net increase of the fecundity of the whole population, when compared to populations in which such factors are lower or absent. This increase grows as the population baseline fecundity decreases; this means that the genes influencing male homosexuality end up playing the role of a buffer effect on any external factors lowering the overall fecundity of the whole population.

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You have it backwards. What this suggests is that there is a genetic variation that gives females higher fecundity and that the homosexuality is linked to this variation.The modeling answers your questions:
It has an affect on a population's dynamic equilibrium -- the population naturally settles into a balance that maintains a higher overall fecundity.
I don't know what you mean by "good for" a dynamic equilibrium -- to me the question makes no sense at all.Likewise, what do you mean by "good ...for" Darwinian NS. That is exactly how the model was constructed. We observe a link between the occurrence of homosexuality in males and increased fecundity in female relatives. Thus NS will produce a particular balance in a population. That balance depends on the apparent negative fecundity affects of homosexuality (a particular fetish of yours) and the positive affects of that gene(s) (or linked genes) on female reproduction.It explains to you exactly how it is possible for homosexuality to be maintained in a population but only if it is genetic.

I have no idea what you mean. Could you clarify please?

That is precisely what the paper is talking about. You seem to have harped a lot on the negative affects of homosexuality on reproductive success. What this paper is showing is that if the genetics involved also offer some positive effects in the population as well you get a dynamic balance in the population.This is the same kind of population dynamics that goes on in malarial areas with the sickle cell gene. It is very bad (read fatal) to have two copies of this gene. However, having one copy isn't so bad but isn't so good either in non-malarial areas. In malarial areas having one copy confers an overall advantage. Thus population modeling can tell you where the population will balance out - not too many copies of the sickle cell allele but still some.This puts to rest your overly simplistic model that says if an individual doesn't breed then NS will remove the genes from the gene pool. This turns out to be wrong.

It doesn't??? Please explain.

Actually, I think it is clear that you don't know.The available evidence is that all sexual orientations are caused in the same way.

Why do you think this is silly? As I said, it seems very clear that you haven't a clue about what causes either. You still haven't said what you think causes heterosexuality. What exactly do you mean by "aberration". That word seems loaded with some negative connotations.It is in fact just part of the wide variation in sexual orientations that humans (and other animals have). There are individuals (about 1%) who are asexual (no interest at all). I might consider that an aberration but it isn't any more aberrant than my interest in women it is just less common. It is part of a continuum of human variation.One person might be asexual, one a bit interested in sex another very interested indeed. Someone mildly interested might decide that anothers stronger interest is "aberrant". But on what basis?Humans also run a gamut of degrees of orientation toward the opposite or same sex. There is no hard and fast line. All the information I have seen suggests that sexual orientation (where ever it is on this continuum) is all underlain by the same causes.Humans aren't even completely divided into male and female. There are individuals who are on the line between and some a bit closer to the line between (but still on one side or the other) than the majority.If you don't think it is a "bad" aberration then why is a way of nature telling us we are in serious trouble? It is just part of the way the population as a whole is made up.How about, for a change, you answer some of the questions put to you instead of making childish little comments?

That's the kind of comment I meant before. It doesn't make you look all that clever.

We don't know precisely what causes any sexual orientation. We do have pretty reasonable evidence that it is genetic and developmentally influenced. The influences seem to be the same for the entire range of orientations.You have ignored this over and over and have offered no reason to not accept this.Your idea that being raised by a gay couple may influence the orientation of a child is something that I have never seen any support for whatsoever. And I'm sure you don't have an once of support for it.In fact, I think (but don't know) that twin studies suggest that this is clearly wrong.

We are, in this thread, discussion biological and other causes of sexual orientations so your wierding out about it is off topic here but...It is obvious your reasons for arguing are just your ickyness on the idea of some kinds of sex. Sex practiced by heterosexual couples by the way.Since there are, probably, a number of perfectly straight women who would be seriously ickied by the idea of sex of any kind with you then I assume that heterosexuality is also wrong in some way.In fact, I know that many lesbian women are not to keen on the thought of heterosexual sex even when they aren't engaging in it. That, apparently, means you think they have the right to take legal actions against it.In addition, today anything which reduces the overall fecundity of hmans might be the only thing which saves us and the planet. We are probably in the 5 to 10 times carrying capacity range already.