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  • Cited by 3
  • Print publication year: 2019
  • Online publication date: November 2019

10 - Adoption in the Taï chimpanzees: costs, benefits and strong social relationships


In a competitive environment, helping others at a cost presents a puzzle. Nonetheless, altruistic behaviour has been associated with human success as a species. Adoption, the provision of alloparental care to an orphan by an individual other than the biological mother, is a potential altruistic act in both humans and chimpanzees. We investigated potential benefits of adoption (like kin selection, improved reputation, or recruitment of allies) in a chimpanzee community with high adoption rates and alloparental care by adult males, who typically provide no paternal care to offspring. The probability of an adult male providing care to an orphan was connected to the grooming relationship/bond between male and mother before her passing and was not influenced by orphan sex or relatedness. The probability of positively interacting with orphans was negatively affected by the number of female bystanders. Results suggest that male–orphan interactions are not solely driven by reputation, ally recruitment, or kin selection and highlight the link between highly prosocial behaviours and social closeness.

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