In the mammal kingdom, only 10 percent of top males can pregnant the prettiests women and populate the species...Since men also have a X chromosome explain why women have twice as much DNA? Not that I doubt that hypergamy is an inherent part of sociobiology since women are can give birth but men cannot that is why they look for a mate that can provide and protect while they're pregnant or nursing.
50 50 male and female ratio and the unit of family, marriage is not biologically natural...
Most men in the prehistoric past died as virgin and never had chance to mate.