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Reproductive inequality in humans and other mammals
Cody T Ross1,2, Paul L Hooper1,3, Jennifer E Smith4
1Santa Fe Institute, Santa Fe, NM 87501.
Summary
Humans show less reproductive inequality than most mammals, with males having fewer offspring disparities. This pattern is linked to human cooperation, resource competition, and social norms like monogamy.
Area of Science:
- Evolutionary biology
- Human behavioral ecology
- Mammalian reproductive strategies
Background:
- Human exceptionalism often overlooks reproductive inequality.
- Understanding human reproductive skew provides insight into species-specific adaptations.
Purpose of the Study:
- To compare human reproductive inequality with that of other mammals.
- To investigate factors contributing to human reproductive skew patterns.
Main Methods:
- Comparative analysis of reproductive skew across mammalian species.
- Examination of human reproductive skew in relation to mating systems (monogamy/polygyny).
Main Results:
- Humans exhibit lower male reproductive skew and smaller sex differences in skew compared to most mammals.
- Female reproductive skew is higher in polygynous human populations than in nonhuman polygynous mammals.
- Human reproductive skew is influenced by monogamy prevalence, limited polygyny, and resource competition.
Conclusions:
- Human reproductive inequality is shaped by unique species characteristics.
- Cooperation, resource dependence, parental investment, and social institutions contribute to muted reproductive inequality in humans.
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