Reproductive inequality in humans and other mammals.

Cody T Ross

; Paul L Hooper ; Jennifer E Smith ; Adrian V Jaeggi

; Eric Alden Smith

; Sergey Gavrilets

; Fatema Tuz Zohora ; John Ziker

; Dimitris Xygalatas

; Emily E Wroblewski ; +94 more... Brian Wood

; Bruce Winterhalder

; Kai P Willführ ; Aiyana K Willard ; Kara Walker ; Christopher von Rueden

; Eckart Voland

; Claudia Valeggia ; Bapu Vaitla ; Samuel Urlacher

; Mary Towner ; Chun-Yi Sum

; Lawrence S Sugiyama

; Karen B Strier

; Kathrine Starkweather

; Daniel Major-Smith ; Mary Shenk

; Rebecca Sear

; Edmond Seabright

; Ryan Schacht

; Brooke Scelza ; Shane Scaggs

; Jonathan Salerno

; Caissa Revilla-Minaya ; Daniel Redhead ; Anne Pusey

; Benjamin Grant Purzycki

; Eleanor A Power

; Anne Pisor ; Jenni Pettay

; Susan Perry

; Abigail E Page

; Luis Pacheco-Cobos

; Kathryn Oths

; Seung-Yun Oh ; David Nolin ; Daniel Nettle ; Cristina Moya

; Andrea Bamberg Migliano ; Karl J Mertens

; Rita A McNamara

; Richard McElreath ; Siobhan Mattison

; Eric Massengill ; Frank Marlowe ; Felicia Madimenos

; Shane Macfarlan

; Virpi Lummaa ; Roberto Lizarralde ; Ruizhe Liu ; Melissa A Liebert

; Sheina Lew-Levy ; Paul Leslie

; Joseph Lanning ; Karen Kramer ; Jeremy Koster ; Hillard S Kaplan

; Bayarsaikhan Jamsranjav ; A Magdalena Hurtado

; Kim Hill

; Barry Hewlett ; Samuli Helle ; Thomas Headland ; Janet Headland ; Michael Gurven

; Gianluca Grimalda

; Russell Greaves ; Christopher D Golden

; Irene Godoy

; Mhairi Gibson

; Claire El Mouden ; Mark Dyble ; Patricia Draper ; Sean Downey

; Angelina L DeMarco ; Helen Elizabeth Davis

; Stefani Crabtree

; Carmen Cortez ; Heidi Colleran

; Emma Cohen ; Gregory Clark

; Julia Clark ; Mark A Caudell

; Chelsea E Carminito ; John Bunce

; Adam Boyette ; Samuel Bowles

; Tami Blumenfield

; Bret Beheim ; Stephen Beckerman ; Quentin Atkinson

; Coren Apicella ; Nurul Alam

; Monique Borgerhoff Mulder

; (2023) Reproductive inequality in humans and other mammals. Proceedings of the National Academy of Sciences of the United States of America, 120 (22). e2220124120-. ISSN 0027-8424 DOI: 10.1073/pnas.2220124120

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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.