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Human Nature

, 19:249 | Cite as

Allomaternal Care among the Hadza of Tanzania

  • Alyssa N. Crittenden
  • Frank W. Marlowe
Article

Abstract

Cooperative child care among humans, where individuals other than the biological mother (allomothers) provide care, may increase a mother’s fertility and the survivorship of her children. Although the potential benefits to the mother are clear, the motivations for allomothers to provide care are less clear. Here, we evaluate the kin selection allomothering hypothesis using observations on Hadza hunter-gatherers collected in ten camps over 17 months. Our results indicate that related allomothers spend the largest percentage of time holding children. The higher the degree of relatedness among kin, the more time they spend holding, supporting the hypothesis of nepotism as the strongest motivation for providing allomaternal care. Unrelated helpers of all ages also provide a substantial amount of investment, which may be motivated by learning to mother, reciprocity, or coercion.

Keywords

Allomothers Child care Cooperative breeding Hadza Hunter-gatherers Kin selection 

Notes

Acknowledgments

This research was supported by NSF grants #9529278 and #0544751 (to FWM) and grants from the University of California, San Diego (to ANC). We would like to thank Dave Zes (UCLA) for the assistance with the statistical program R, and Donna Leonetti, Shirley Strum, Pat Draper, and the five anonymous reviewers who provided helpful comments and suggestions that greatly improved this manuscript. We are grateful to Lene and Johannes Kleppe for their generous hospitality, to our Tanzanian research assistants for their dedication, and to COSTECH for research permission. We are greatly indebted to the Hadza families who welcomed us into their lives.

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Copyright information

© Springer Science + Business Media, LLC 2008

Authors and Affiliations

  1. 1.Department of AnthropologyUniversity of CaliforniaSan DiegoUSA
  2. 2.Department of AnthropologyFlorida State UniversityTallahasseeUSA

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