That got your attention, huh?
Here's the thing: Homosexuality actually is necessary from an evolutionary perspective.
How, you ask?
Survival of the species.
From a perfectly natural, scientific stand point, the FACT (yes, I'm using that word on purpose) that some people (and even some animals) are born gay is a matter of genetics, and biological imperative. It really is that simple, and there isn't a fucking thing wrong with it. Pun completely intended.
I know there will be people that blink angrily at the very notion that as a straight man, I'm talking about homosexuality, but hear me out. I'm not claiming to know what it's like to be a gay man or a lesbian in today's bigoted society, and I'm not claiming to know firsthand of the atrocities and prejudices they all face. In fact, I acknowledge the opposite. I'm speaking from a scientific and evolutionary angle.
So here's the thing: A great many Christians like to point out what they perceive as a fact that homosexuality disproves evolution because it dead ends survival of the species. (Cue obnoxious game show buzzer sound).
Wrong.
In reality, it actually proves survival of the species. Homosexuality is the most natural form of population control there is. Overcrowding will choke out the species - any species. It's that simple. I know, Christians, I know... "If evolution makes people gay, why isn't everybody a fag, then, huh Mr. Smartypants!?"
Simmer the fuck down.
I didn't say evolution makes people gay, I said homosexuality is a result of evolution and biological imperative. Survival of the species does demand that animals reproduce, but that isn't the only thing necessary for survival. Food, water, shelter, and space are also all necessary. This is why some of the population is born homosexual, and some are born heterosexual. Evolution is a series of genetic variants. if it weren't for these variants, we'd all still be one-celled organisms.
Make no mistake: Survival of the fittest, and survival of the species are two different (yet obviously linked) things. One, survival of the species, is the idea that from the point of biological imperative, members of a given species will act in such a way as to ensure the survival of the entire group. This is evidence that morality and altruism are in fact byproducts of evolution, and we don't need a magical tome to tell us what to do and not to. The other, survival of the fittest, is a matter of natural selection as well as an explanation of who eats who and why. This is the one with which Christians like to try to disprove evolution.
The ultimate point here, and one that science has backed up, is that it really doesn't matter who you as an individual fuck. What matters is that enough of the population of a given species fucks in such a way as to keep the species going. The laws of nature are not bigoted, and as a result, everyone is given an equal opportunity to fuck whomever they wish, it's just that some of that fucking will not result in progeny. It really is just a matter of evolution and survival of the species.