I once had a religious friend tell me that homosexuality is unnatural and a sin, as evidence, cited that humans are the only species to engage in same gender sex. Here’s an interesting article on homosexual behavior in animals:
http://www.livescience.com/animals/080516-gay-animals.html
However, just because animals do something doesn’t make it okay for humans to do it. For example, if a dog is sexually attracted to a human leg, that doesn’t make bestiality okay (although a lot of canines would disagree with this).
The point is that Homo sapiens are not the only species that have homosexual tendencies.
Humans do seem to be the only homophobic species. They tend to attack anything that they perceive as being not like them. Religions fan the fire because it gives them control over their members, which keeps the money coming in.
What did Jesus say about bedroom behavior? He said “judge not” and “love thy neighbor as yourself”. What consenting adults do behind bedroom doors is nobody else’s business. And it’s certainly not your hegemonic Bishop’s business.