Oolon Colluphid

Now now, if you’ve read any of Abe’s previous posts you should know that he’s actually rather intelligent and knowledgeable... (though he hides it quite effectively under a stream-of-consciousness writing style...

Oolon

Dr Rick

Evidence suggests that humans probably do have genetic predilections towards certain behavours, and I would not argue otherwise. But most human behavour seems much more influenced by learning and environment than by genes, and that includes homosexuality. If that is the case, then homosexuality does not have a "genetic basis" but rather a "learned basis" with some genetic component. This would make the speculation about the topic of this thread, an "evolutionary explanation for homosexuality" tenuous at best.
I question the existence of "strong deterministic factors" if this term is meant to mean genetically pre-determined behavour when environment and learning probably have a much greater influence.

theyeti

But the environment can be deterministic too, especially during early childhood or fetal development. I think the idea that homosexuality is "deterministic" is borne out mostly be observation. But this does not necessarily mean it's genetic.

theyeti

theyeti

I can agree with this. I would only add that evidence suggests that there is at least some genetic predilection. Whether it's major or minor is pending further research, although such research is often frowned upon by ethicists.

Still though, if we assume that natural selection determines the frequency of gene alleles such that each one will on average produce the same number of copies of itself, there's nothing wrong with trying to find an evolutionary explanation for those frequencies. If nothing else, it's a fun exercise. It's not too different than the "evolution and religion" thread that we had awhile back. If we choose to assume a genetic basis, then it's worth exploring evolutionary hypotheses.

theyeti

Dr Rick

You're seem to be arguing that one human sexual preference is genetically determined but not the others. This dichotomy is not only arbitrary; it contradicts the rest of your argument. You appear to be claiming that not only is there a genetic basis for homosexuality but there is an as yet unstated evolutionary explanation for it even though it is the one trait among those mentioned that is most likely to interfere with reproduction (Having pooh on one's breath probably doesn't do much to improve one's chances of mating, either).

A different species with a different set of behaviors and motivations. Theyeti, you can't just pull any old animal behavior out of a hat and expect it to be analagous to human behavior . Since other animals are different from humans, how do you know which animal behaviors are analagous to humans' and which are not? Just because an animal behaves a certain way does not mean that we can draw conclusions about humans from it.

Rick

Dr Rick

It has been a fun exercise; and your point about the frequency of homosexuality does make a strong case in favor of an evolutionary basis for the genes to which it may be linked.

Rick

theyeti

No Rick, I'm arguing that these other behaviors don't present a paradox. I would be surprised if there was not a genetic basis (though probably indirect) to those other behaviors as well, and probably to sexual deviancy in general. But unless that deviant behavior prevents someone from surviving or reproducing, then there's no real mystery about it. People bring up this "evolution and homosexuality" thing all the time because it's something that, on the surface at least, seems to go against the grain of evolution. There's nothing about eating doo doo, aside from being nasty, that makes us wonder why natural selection doesn't strongly disfavor it.

What we do know is that other animals have behavioral patterns that are determined almost exclusively be genetics. We therefore know that behavior can be genetic. We also know that we human being are related to those animals, and therefore it is reasonable to conclude that our behavior has a genetic component too, though our ability to learn and think throws an interesting twist on it. IMO, it's inappropriate to ask whether or not a behavior is genetically determined. The proper question to ask is how our genetics are interacting with the environment to produce that behavior. In many cases our genotype will not predict behavioral outcomes better than chance, but in many other cases it will.

As for specific behavioral patterns, it doesn't do us much good to look at other animals unless we can identify homologous genes that tend to lead to those patterns. Probably the only animals worth looking at are the grate apes, and there has been a fair ammount of success in understanding our own behavior by observing theirs.

theyeti