Search

Data, Materials, and Software Availability: All study data are included in the article and/or supporting information available online at https://www.pnas.org/lookup/doi/10.1073/pnas.2220124120#supplementary-materials . Copyright © 2023 the Author(s). To address claims of human exceptionalism, we determine where humans fit within the greater mammalian distribution of reproductive inequality. We show that humans exhibit lower reproductive skew (i.e., inequality in the number of surviving offspring) among males and smaller sex differences in reproductive skew than most other mammals, while nevertheless falling within the mammalian range. Additionally, female reproductive skew is higher in polygynous human populations than in polygynous nonhumans mammals on average. This patterning of skew can be attributed in part to the prevalence of monogamy in humans compared to the predominance of polygyny in nonhuman mammals, to the limited degree of polygyny in the human societies that practice it, and to the importance of unequally held rival resources to women’s fitness. The muted reproductive inequality observed in humans appears to be linked to several unusual characteristics of our species—including high levels of cooperation among males, high dependence on unequally held rival resources, complementarities between maternal and paternal investment, as well as social and legal institutions that enforce monogamous norms. This work was conducted as a part of the “Emergence of Hierarchy and Leadership in Mammalian Societies” group at the National Institute for Mathematical and Biological Synthesis, supported by NSF Award DBI-1300426 and the University of Tennessee, Knoxville. It was supported by NSF awards SMA-1329089 and SMA-1743019, and the Santa Fe Institute, as well as the Max Planck Institute for Evolutionary Anthropology, Department of Human Behavior, Ecology and Culture. S.G. was supported by the US Army Research Office grants W911NF-14-1-0637, W911NF-17-1-0150, and the Office of Naval Research grant W911NF-18-1-0138. Additional funding for data collection was provided by the Wenner-Gren Foundation for Anthropological Research awards: 8913 and 7970, by NSF awards: BCS-0924630, BCS-0925910, BCS-0848360, BCS-0514559, BCS-0613226, BCS-0827277, SES-9870429, and DDRIG-1357209, by the National Geographic Society awards: HJ-099R-17, 20113909, 8671-09, and 7968-06, by the Kone Foundation awards: 086809, 088423, and 088423, and by the Jacobs Foundation, the UCSB Broom Center for Demography, and the UCSB Department of Anthropology.

Data availability statement: All data and code to reproduce the present study are available at: https://github.com/tbendixen/cross-cultural-free-list-project. The main project repository including raw data, full protocols, and related materials is available at: https://github.com/bgpurzycki/Evolution-of-Religion-and-Morality . The file available on this institutional repository is a preprint available on PsyArXiv at https://psyarxiv.com/tjn3e/. It has not been certified by peer review. We recommend you consult the version of record published by Routledge at https://doi.org/10.1080/2153599X.2023.2178487. How do beliefs about gods vary across populations, and what accounts for this variation? We argue that appeals to gods generally reflect prominent features of local social ecologies. We first draw from a synthesis of theoretical, experimental, and ethnographic evidence to delineate a set of predictive criteria for the kinds of contexts with which religious beliefs and behaviors will be associated. To evaluate these criteria, we examine the content of freely-listed data about gods’ concerns collected from individuals across eight diverse field sites and contextualize these beliefs in their respective cultural milieus. In our analysis, we find that local deities’ concerns point to costly threats to local coordination and cooperation. We conclude with a discussion of how alternative approaches to religious beliefs and appeals fare in light of our results and close by considering some key implications for the cognitive and evolutionary sciences of religion. Cultural Evolution of Religion Research Consortium, funded by a SSHRC partnership grant and the John Templeton Foundation (awarded to A.N. and J.H.); B.G.P. acknowledges support from the Max Planck Society; T.B. and B.G.P. acknowledge generous support from the Aarhus University Research Foundation.