Sex and its irrationality

I am probably your average heterosexual male specimen. Having gone through a younger period where sex is at the top of my list of priorities, my hormones have calmed down somewhat and now it appears I can finally examine sex with more rationality.

Recently it is beginning to get to me that sex is not something that one can rationalize. It lies outside the realms of rationality. The fact that a heterosexual male gets aroused by the sight of breasts or the vagina is not something one can deconstruct. In fact, there is nothing inherently attractive about these things other than the fact that millions of years of evolution have built their sense of attractiveness into us, without which our species cannot survive. If an alien from another planet were to land on Earth, they will never understand why we find breasts or vagina sexy, much as we can understand how a peahen will find the large and bright tail of a peacock sexy.

And we have discovered for a long time that there is a large variety of sexuality outside of the standard male-female model. You have the asexual (not interested in sex), homosexual (interested in same sex), heterosexual (interested in opposite sex), bisexual (interested in both sexes), transgender (female persona trapped in a male body, and vice versa). Within a particular category, there are also huge variations i.e. interest in different sexual organs, or even symbolism of sex (eg. brassiere or panties).

It is probably unique to the human species that we have the mental capacity to tie ourselves in knots over variances in sexuality outside of the standard model. There have probably been more debates about the morality/immorality of sexual variances than how to rid our world of hunger. Heterosexuality, being the majority, has always occupied the moral high ground. Other forms of sexuality have always been the deviant form. In some countries, being homosexual or transgender can get you killed. In fact, I have encountered few people who even understand the difference between being homosexual and being transgender. Most people still associate being effeminate as being homosexual (for males), for example.

It puzzles me to no end how most people do not question the irrationality of heterosex itself, that finding sexual organs of the opposite sex attractive is just as illogical as finding sexuals organs of the same sex attractive. To most people, heterosex is just "natural", whereas other forms of sexuality are not. This is crazy, and how people can live with that conclusion is beyond me. It is probably the highest form of prejudice there ever is, that your irrationality is somehow more "natural" than some other irrationality. I mean, this is not some argument over whether one algorithm is better than another, because then you can use logic/numbers to justify your decision. This is a case of my preference is more "natural" than yours and 1) that's it, 2) end of discussion, 3) you are a deviant/outcast.

Is it just me, or does anyone else find this crazy as well?