Reproductive investment asymmetry drives sex differences in mate selection and aggression

Evidence

From an evolutionary perspective, one could argue that many of the robust psychological differences between men and women can be explained in terms of the differential reproductive opportunities and risks by which male and female mammals are constrained. Because of the way mam malian reproductive systems are designed, females are obli gated to invest much more heavily in offspring than are males— even before socialization of offspring occurs—in terms of time, energy, and resources associated with fertilization, gestation, parturition, and lactation. … In sharp contrast, males have no physiological obligations in offspring past successful fertilization. This stark asymmetry in obligate physiological investment between the sexes sets the stage for complementary asymmetries in behavioral strategies to cope with these realities. As the higher investor in the mating transactions necessary to produce offspring, females are more discriminating in their choice of a candidate from the lower investing sex. Females also do not experience reproductive benefits from engaging in extra matings between conception and weaning. This leads to a female mating strategy that can be described as one primarily concerned with selecting mates of high quality (as mating strategies that maximize quantity are of little benefit to females), so as to not waste their costly investment. … On the other hand, because males are not burdened with the same obligate costs in producing offspring, they are the less choosy sex. In contrast to the low reproductive benefits available to females pursuing multiple matings, males benefit more from a quantity mating strategy as their reproductive success rises as a function of the number of fertile mates with whom they copulate. These conflicting prerogatives of males and females create an incentive structure that rewards the lower investing sex for engaging in risky, aggressive, and often dangerous strategies for eliminating or neutralizing same-sex competitors in order to increase one’s mating access to the higher investing sex. — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 1181

From an evolutionary perspective, one could argue that many of the robust psychological differences between men and women can be explained in terms of the differential reproductive opportunities and risks by which male and female mammals are constrained. Because of the way mam malian reproductive systems are designed, females are obli gated to invest much more heavily in offspring than are males— even before socialization of offspring occurs—in terms of time, energy, and resources associated with fertilization, gestation, parturition, and lactation. … These conflicting prerogatives of males and females create an incentive structure that rewards the lower investing sex for engaging in risky, aggressive, and often dangerous strategies for eliminating or neutralizing same-sex competitors in order to increase one’s mating access to the higher investing sex. — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 1181

Categorization

• DEFINE: Lays out the parental investment asymmetry framework clearly and concisely.
• XREF: The classic Trivers parental-investment theory argument; connects to standard evolutionary-psychology models of sex-differentiated mating strategies and competitive aggression. — connects to: Biological egg structure does not dictate the degree of female parental involvement; Biology refutes both the female-passivity bias and the male-effervescence bias at the gamete level — Simone de Beauvoir, The Second Sex, 85
• corroborated: 3 independent passages support this claim — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 1181