Robot Macai
People have asked where I get my information about the psychological dogma of all behavior being societal rather than genetic, and I must admit that I was intending this as a jab against Meroko Love and Blind Guardian, and their supporters, but I guess I failed to make it obvious enough.
I can't speak for Meroko_Love's position, but you have got BG's incorrect. He doesn't say that nature plays no part; what he says corresponds with current neuroscience-- that "nature" needs to be activated in a sense by "nurture," thus making "nurture" the bigger component.
I think I already went over this with you but I'll give you the short version (again?): Humans have the largest fully developed brains, brains so large that they cannot pass through the average female's pelvis. The evolutionary trade-off is to a smaller extent larger pelvises, but mainly humans being born more prematurely than, IIRC, any other mammal. In most instances it takes more than 25% of a human's lifespan for its brain to fully develop, and elsewhere and in the past, it took around and well over 50%. That leaves humans far more vulnerable to the "nurture" end of the spectrum than almost any other animal. (It is also probably the main the problem with comparing homosexuality in other animals with homosexuality in humans.) It should also be noted that we are far less vulnerable to the effects of "nurture" once our brains develop fully.
In short, it's not that nature plays no part, but that, at least for things like this, nurture plays the bigger role.
^ Because you asked for an explanation.