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  • Print publication year: 2019
  • Online publication date: November 2019

20 - Why do the chimpanzees of the Taï Forest share meat? The value of bartering, begging and hunting


Meat sharing is common in chimpanzees. While being well-studied, it is still unclear what drives meat owners to relinquish nutritional benefits in favour of group members. The topic is rich in theoretical models, with support for different hypotheses coming from various chimpanzee populations. Few studies have considered several alternative hypotheses simultaneously, which provides insight into how multiple mechanisms interact to enable meat sharing. We investigated whether Reciprocal Altruism, Sharing-under-pressure, Mutualism, or Costly Signalling can explain meat sharing in Taï chimpanzees. We found evidence that chimpanzees exchange meat for support in aggressive interactions, supporting Reciprocal Altruism. We found partial support for Mutualism, as individuals who caught the prey ate more than others, and hunters who begged were more likely to receive meat than others. Finally, we found that begging led to sharing, possibly supporting the Sharing-under-pressure hypothesis. Various mechanisms can lead to meat sharing; the prevalence of one mechanism over another might result from their ability to adapt to the specific environmental and social conditions of the population.

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