Even So I'am Pro-CHoice

Here is an essay I found on the web. I can't give the proper credit because the person just went by the name of Wulf.

If you're still under the impression that homosexuality is a choice:
You're confused about the facts. You're wrong about the science.
I'm sorry to be so blunt, but a lot of specious arguments have been invoked here to defend that mistaken belief, including burglary, bestiality, and the Bible.
Could we have some minimal standards for evidence, please? This isn't a political question, or a moral question, or a theological question--it's a scientific question. It's a question about human behavior, about human nature, about biology, about why we do what we do. And you don't have to be a card-carrying scientist to approach the question analytically. But you have to be willing to give up a comforting or cherished belief--you have to be willing to go where the evidence leads.
Because this is a question about human sexuality, there are three possible sources of evidence:
--what we (collectively) observe _--what others report _--our own introspection
Since we know that human beings don't always understand why they do what they do or feel what they feel, and since we know that human beings sometimes lie about what they do know, we have to approach the second and third potential sources of evidence with caution.
One other caution: whatever conclusion we come to about homosexuality needs to make sense in the context of the rest of human sexual behavior (and, for that matter, primate sexuality and mammal sexuality in general). We can't have a special theory for homosexuality in isolation.
So what kind of observational evidence do we have a reasonable consensus on?
--Among mammals generally, females are attracted to males and males are attracted to females.
--However, homosexual acts have been observed in many mammal species, and
--Homosexual pairings have been observed in other social, pair-bonding species.
--There are significant differences between male and female sexual behavior (biologists call this "sexual dimorphism").
--These differences in behavior are linked to differences between male and female brains and between male and female endocrine systems (hormones).
--The level and mix of our sex hormones affects our social-sexual behavior. Alter the level or the mix and you alter the behavior.
--We all started out female. The basic human body plan is female. It takes at least three 'hormonal events early in a pregnancy to transform this default female design into the modified male version. The changes include altering the fine structure of the developing brain--not only how it is 'wired,' but how it will respond to sex hormones at puberty. Neurologists have labeled this process "masculinizing the brain."
--Because of this complex transformation process, and the possibility that it is disrupted, not every outwardly male body contains a fully "masculinized" brain (and not every outwardly female body contains an unaltered female brain). In fact, a wide range of variations is possible.
What are the implications of this evidence? That there exists a natural developmental path which can account not only for 'instinctive' heterosexuality, but male homosexuality, female homosexuality, true bisexuality, and gender dysphoria (both "a woman trapped in a man's body" and "a lesbian trapped in a man's body"). It's possible that all sexual orientations trace their origin to this process.
Would that explain all human sexual behavior? No. Just as with food, we are creative pleasure-seekers. We are fully capable of experimenting with toys, textures, electricity, intense sensations, fruits and vegetables, other species, our own sex, in the pursuit of pleasurable experiences. And when we find one, we're generally inclined to repeat it. Here's where we do see a significant element of choice. Here's where we get a lot of sexual acts (by straights, gays, bisexuals) which have no obvious connection to reproduction.
For my money, this model does a good job of accounting for what we see: most sexual behavior (of all orientations) driven by deep instinctive drives, some driven by experimental pleasure-seeking. The remainder, sadly, probably has to do with people who are in one way or another damaged goods--with enough power over someone, you can warp and even break them sexually (something all too often done in the name of an Abrahamic religion).