Arf. Well the joke is on Sociopath coz if you're gonna insist on some kind of biological explanation ("men and women are just different" - as if there were only two simple biological sexes, let's not even begin to talk about gender and gendering) then the biological evidence suggests that the shape and size of the human dick evolved in the cauldron of *women's* 'promiscuity'. (Exhibit A: the shape of the human dick head sluices liquids - such as cum from the last visitor - behind itself so that they are drawn out of the vagina. And its grown big enough (much bigger than any other primate's relative to size, as Vizzero pointed out) to get the swimmers right to the mouth of the womb.
Sociopath's also wrong about polyandry. There were (maybe still are) polyandrous (many-husband/male consort) societies: some place in Tibet ?or Mongolia? where people marry late in life and a woman's brothers take responsibility for her children and people expect active and varied pre-marital sex life); Some people in Nigeria where everyone makes multiple marriages (boy children stays with dads and girls move with their mothers). Parts of India, I think. They're not all kind to women (or necessarily men) I should add. I know nothing about European or the Americas marriage traditions but i;m sure you'll find similar there.
Of course Sociopath's wrong to assume in the first place that marriage conventions represent actual sexual behaviours in a society, or that actual sexual behaviours represent natural human tendencies.