The present is the consequence of the past, and the future is the result of the present.
That's a simple idea, but I think that more of the people don't get it right. I'm used to hear that "this/that don't follow the law of nature". In the nature, there is a lot of imperfections and mutations that happens all the times, babies with two heads, one arm, etc. If any kind of mutation is better than the original, then, as a result that individual maintains the specie, then that mutation will be more common, until (if everything goes OK to that mutation) will be the common denominator of the specie.
But, I think that we had to keep in mind that, the evolution as we see it now, is the result of the uncountable mutations, not a perfect path that the Nature had walked.
As an example, I can think of uncountable racist, that thinks that they are "the pure race". That is quite exotic thought to me. There isn't anything pure in any race (if african/black people, asian, etc could be think as a race, I'm not sure about that).
In the same way, are the catholics that think that be homosexual is against the God's laws and Nature. Is obvious that they don't want the homosexuals had the same rights as the heterosexual has, but the reality is more interesting. I know a lot of homosexuals (more lesbians than gays), and them are respectful and, as they know that some acts could offend some people, they don't try to kiss each other everywhere.
I don't agree very much with the way of some homosexuals don't express themselves everywhere. But, as I'm getting older, I began to get that idea more deeply. And I think that is the best thing that they can do. Everything is related to respect. If I don't respect other people, I could never tolerate an african guy, an asian, a latino, etc. And, the worst to think (specially to some caths) is that Homosexual people choose to be homosexual.
When I think about respect, is not to love or approve everything and everyone. But to think that I'm not God, I don't have the power (nor the right) to govern over other people's thoughts. And is the same in the evolution, if I don't respect that there is no order in the nature, or at least I don't try to simplifier things and think that I understood everything, evolution (or better, the some people that talks about), trends to think that be gay is against evolution, because they can reproduce.
I think that everybody had to get in touch deeply with the idea of respect. So at least, it could be less wars and less suffer (specially, less suffer).