Even if we accept the basic logic of the natural law argument against homosexuality, we have to ask just how wicked a sin it could really be. People … - Steve Stewart-Williams

When it comes to the traits we consider most important in a long-term mate, human beings are largely monomorphic. This is one of the most significant findings of these studies; however, it is easily overlooked when the discussion becomes fixated on traits that people consider less important but where sex differences are found. By shining a spotlight on these traits, we may create an inaccurate picture of our species, even though the differences are real. Our picture of human nature may be built on a foundation of exceptions to the rule. The rule — the fact that males and females in our species are surprisingly similar in many ways — may be relegated to the background. By taking genuine differences and then exaggerating their importance, our picture of our evolved nature may become a caricature: It may contain a recognizable grain of truth but distort its object.

Just as our tools evolved culturally to fit our hands, so too our social roles evolved culturally to fit persisting aspects of the human mind. Roles that jar too violently with human nature are unlikely to persist for long, at least without the application of significant social force. If this is correct, it raises the possibility that some social roles might have evolved culturally to fit traits that, although found in both sexes, are more common in one than the other. This is emphatically not to say that there are some male roles and some female roles. But it is to suggest that there might be some social roles that suit more men than women, and others that suit more women than men — not just because of evolved physical differences but because of evolved psychological differences as well.

"Once a suitable mate is located, humans engage in various peculiar mating rituals. The male, for example, may give the female a bundle of plant genitals (or “flowers”), or the pair may take turns making noises at each other while imbibing fermented plant juice." (Quote from an alien scientists report on our species.)