It isn't "human" it is "cultural". Still shouldn't deny it, but it can and will change. (And has changed a lot already!)

So you mean in other cultures looks don't matter? Maybe if the parents set up the marriages? Do you have any references?

I don't mean other existing cultures are different. (Although, there are differences.)

I mean it is a matter of culture (ideas) not "humanity" (DNA).

There are many reasons to believe this. Two are:

- memes evolve orders of magnitude faster than genes, so once they existed, they responded to almost all selection pressures first. anything with complex social interactions that require intelligence couldn't have evolved before memes (ie, before we had intelligence).

- people sometimes make changes to how they treat women, how they interpret appearances, to all sorts of related ways of thinking and behaviors. this points to culture because our ideas are designed to be changeable at runtime, and our DNA isn't.

Sexual attraction seems kind of important to the survival of humans, though. Or at least it used to be (cloning and stuff like that might change that).

Of course there are cultural aspects to how women are being treated. Granted, there could be cultures where people would not automatically remark on the attractiveness of a female colleague. For example, if all women are hidden behind veils, and infidelity can get you killed, maybe people are much more careful about what they say (just guessing, I don't know).

Before intelligence, there was no such thing as 'sexual attraction' in the current sense. There was only the exact same thing animals have: programs that behave in certain ways, based on certain inputs. Like a DARPA car steers left on certain input, an animal has sex on certain input.

With the advent of intelligence, came the ability for high-level interpretation of sense input -- we might say that events took on meaning. From a survival point of view, the ability to reinterpret arousal chemicals, and other things, was no serious danger: any culture that did that would die out. (And even if it was dangerous for the species, evolution doesn't do advanced planning of that sort.)

What we have today, and call sexual attraction, involves many layers of intelligent interpretation, which we (largely unintentionally) teach to the next generation -- ie, it is culture. If parents behaved differently, the meaning of sexual attraction would change.

Edit: By analogy, DNA = assembly language. We program in higher level languages. (Imagine programming in 500 years though, so it's much further removed from assembly). At some level of abstraction, the original details of DNA/assembly are totally irrelevant to the level we normally think in.

I remain skeptic. Sure, there are cultural signals we learn to interpret (short dresses, suits, marriage rings,...), but on a basic level, for the most part, women will be attracted to men and vice versa? Diseases will be repellent, as will other attributes of unfitness? You think you can raise men to be gay? (I don't know). Surely there is a lot of research on that, but the final word is perhaps not out yet?

People do raise men to be gay. Happens all the time. A few percent of parents do it (I don't know any reliable statistics). Not on purpose, sure, but parents don't raise straight kids on purpose either. (Yes, people try to "make their kid straight" occasionally, but there's no evidence the things they do actually have the intended effect.)

I definitely think one day we will learn how to analyze what parents do that causes men to turn out gay, and be able to copy it (or not).

However, I won't be surprised if the answer is: all present-day parents enact parenting strategies capable of causing homosexuality, but they only behave to cause it (unintentionally) when triggered in the right way (i.e., by some characteristic of young children other than homosexuality itself).