How does reproductive competition affect investment in bodily repair in males and females?

In the context of Darwinian medicine, natural selection shapes bodies to maximize reproductive success rather than longevity or health. This process involves trade-offs where energy is allocated between reproduction and bodily maintenance, such as protection and repair.1

Reproductive competition significantly influences how these resources are distributed between the sexes. In polygynous species, where males compete intensely for multiple mates, an incremental investment in bodily protection and repair often yields a greater increase in reproductive fitness for females than for males. Because males in these species may achieve high reproductive success through competitive dominance, they may be "selected" to prioritize traits that facilitate mating—such as size or aggression—over long-term somatic maintenance.12

Consequently, this disparity in reproductive strategies helps explain why males in many species experience higher mortality rates and shorter lifespans compared to females. Ultimately, because natural selection favors mutations that increase reproduction even at the expense of health and longevity, the level of investment in bodily repair is fundamentally constrained by the specific reproductive demands placed on each sex.1