Just wanted to simplify my argument.

Environmental factors are the greater cause.

Our brains may be wired a certain way, but they will react/"learn" differently when presented with different situations. Therefore it's our reaction to certain factors in our lives that ultimately decides what orientation we 'choose' whether or not this is in agreement w/ our deeper desires.

Is it then possible to control the outcome by changing the environmental factors? Maybe that is what religion did by shunning homosexuality.

I think we are all bisexually-capable, but environmental factors may limit what we're willing to experiment with.

This could mean that our sexuality is predetermined in our brains and that environmental factors can force one to withhold their homosexual urges.

It could also mean that because heterosexuality was considered the norm (for obvious reasons) early on and still is, it is much more prevalent today. This would also be in favor of "environmental factors" as being the reason.

In conclusion, I think environmental factors often do determine one's outwardly expressed sexual preference regardless of their deeper desires. This can applied to most superficial traits that one may possess.

For instance, if I liked certain songs from Avril Lavigne's first album that my friends would scathe me for, I might deny this fact in public, but listen to her on my own time...lol

Hmm...that's probably a bad example... ;)

Furthermore, I think people think that it's either a "choice" or "genetic". The word choice is misused here. It's made to seem as if there must be an on or off switch. You can't choose, pur sae, but your brain reacts to the environment and the end result will be one or the other (or bisexuality). That doesn't mean that you are pre-wired to be any particular sexuality. That just means that in your particular environment your brain reacted a certain way.

So the idea of choice comes down to whether or not our lives are just the byproduct of our brains reacting to the environment.