Ethology is the study of animal behavior, particularly patterns that occur in natural habitats. From an evolutionary perspective, ethology covers individuals (evolutionary psychology) and groups (sociobiology).
How individuals relate to one another affects both personal and social dynamics. Consistent patterns in these behaviors characterize species sociality.
Human Mating Strategies
In all comparative analyses, humans always fall on the borderline between obligate monogamy and polygamy. While males are more promiscuous than females overall, within-sex variation of these variables is best described by 2 underlying mixture models that slightly favours monogamy in females and promiscuity in males. The presence of 2 phenotypes implies that mating strategy might be under complex frequency-dependent selection. ~ English psychologists Rafael Wlodarski & John Manning, & English anthropologist Robin Dunbar
Men are generally more promiscuous than women. This owes to males having greater reproductive success by their sowing seeds in multiple fields. Meanwhile, women do better reproductively in taking care of their progeny. That withstanding, human mating strategies are more complicated than that. Fidelity is not solely a womanly virtue. Many men are reliable dads and many women sexually stray.
More generally, both sexes adopt distinct mating tactics. From a population perspective, the ideal mating strategy for either sex favors some diversity.
The extreme altricial nature of human offspring means that the optimal population prospect would be for most men to be good fathers. Women may not have more offspring through extra pair-bonding, but the extracurricular activity does produce greater genetic diversity.
One advantage to this comes in disease susceptibility. All the eggs in one genetic basket means a greater chance of one’s progeny being wiped out by an infectious disease outbreak. Better to hedge the bets.
Male cads outnumber dads by a ratio of 57:43. Females with fidelity outnumber loose women by only 53:47. These equilibria correspond with optimal results that might be obtained via game theory, which is the mathematical study of strategic decision-making. At the population level, human mating behaviors follow a coherent mathematical rule set. This statistical coincidence of optimality is mysterious.