I specifically told you animals aren't subject to social pressure. That's what the phrase "without socialization" means. Nice try at the sarcasm though.
http://en.wikipedia.org/wiki/Homosexual_behavior_in_animals
(Sorry to quote wikipedia, but their source is behind a paywall.)
One species in which exclusive homosexual orientation occurs, however, is that of domesticated sheep (Ovis aries).[9][10] "About 10% of rams (males) refuse to mate with ewes (females) but do readily mate with other rams."[10]
http://www.nytimes.com/2004/02/07/arts/love-that-dare-not-squeak-its-name.html
Silo and Roy are, to anthropomorphize a bit, gay penguins. When offered female companionship, they have adamantly refused it. And the females aren't interested in them, either.
http://www.independent.co.uk/news/gay-vulture-couple-raise-surrogate-chicks-1110120.html
The adult males, known as Dashik and Yehuda, built a nest last year and set-up home together. In the spirit of gay liberation, they openly and energetically mated, but failed to produce a single egg.
Then, as an experiment, Israeli zoologist Shmuel Yidov took a day-old vulture chick that had been hatched in an incubator, inserted it carefully inside a swan's egg and slipped it into the nest. Fooled, the pair took turns to sit on it and warm it until it hatched again.
So, tell me again how animals only do it for dominance or "to get his nut off." And the argument that it's a very small percentage isn't a very good one because it's a very small percentage in humans as well. And if you look at the quote from the rams, they put the number of homosexual rams at about 10%, which last I checked is higher than the number of homosexual humans.
And you have a seriously warped view of sexuality. Sexuality is fluid, not static as you seem to think it. Same-sex encounters do not make one homosexual, anymore than lying once makes someone a habitual liar.
Besides, the nature argument is just one small piece that you seem to be hung up on. What is and isn't natural isn't really all that relevant.