Taken from that article:
"Jean Foucault argues, "...homosexuality became because we made it so" [11]. Foucault says that the category of homosexuality itself was only created a mere one hundred years ago, after a German neologism coined some twenty years later. Foucault gives root to the social derivation of homosexuality believing that homosexuality appeared as one of the forms of sexuality, only "after it was transposed from the practice of sodomy into a kind of interior androgyny, a hermaphrodism of the soul" [10]. The theorists believe that the homosexual had been an aberration, and had then become a species, justifying itself with a new word. "
"We have examined many causes for homosexuality in the preceding pages, both biological and social. And although an interesting topic of debate, no one theory or experiment leads to a definitive answer."
EDIT: as an afterthought, I'd like to apologise for starting a long, boring debate about sexuality on a paintball forum. It wasn't my intention and I didn't anticipate how much of a reaction it'd get. I have trouble "letting it go" so sorry for dragging it out like this. Apologies to anyone I offended or upset.