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Food sharing is a costly form of cooperation that was likely critical to human evolutionary success, including the emergence of human's life history strategy. Food sharing in human communities may be maintained through a number of pathways, including direct dyadic reciprocity, reputation‐based processes, and kin‐biased exchange. Differences in reproductive demands, labor, and cultural norms may also result in gendered differences in cooperative networks. Here, we examine cooperative networks in egalitarian BaYaka foragers from the Congo Basin. We collected social network data from 112 adults in 41 households in this subsistence community. We implement a Bayesian latent network model to assess individual‐, dyadic‐, and block‐level predictors of food sharing partners. Conditioning on covariates, we found limited evidence for direct dyadic reciprocity in food sharing. Despite local norms regarding prestige avoidance, we found status‐based homophily. High‐status individuals—council members and local healers—were more likely to share with one another. Importantly, our results highlight gender differences in patterns of food sharing, interacting with genetic relatedness. Women were more likely to share with one another, especially with kin as genetic relatedness increased. Our results align with evolutionary framing emphasizing kin selection in costly cooperation. The results showing that women cooperate with other women, particularly kin, also complement sex‐based patterns in some other mammalian species, potentially reflecting the social support necessary to manage reproductive costs and childcare. BaYaka women's subsistence productivity and local cultural dynamics for autonomy and egalitarianism may likewise help facilitate women's preferential cooperation with one another.
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Reciprocity and beyond: Explaining meat transfers in savanna‐dwelling chimpanzees at Fongoli, Senegal
Abstract ObjectivesTo understand the function of food sharing among our early hominin ancestors, we can turn to our nonhuman primate relatives for insight. Here, we examined the function of meat sharing by Fongoli chimpanzees, a community of western chimpanzees (Pan troglodytes verus) in southeastern Sénégal. Materials and MethodsWe tested three non‐mutually exclusive hypotheses that have been used to explain patterns of food sharing: kin selection, generalized reciprocity, and meat‐for‐mating opportunities. We analyzed meat sharing events (n = 484) resulting from hunts, along with data on copulations, age‐sex class, and kinship to determine which variables predict the likelihood of meat sharing during this study period (2006–2019). ResultsWe found full or partial support for kin selection, direct reciprocity, and meat‐for‐mating‐opportunities. However, the analyses reveal that reciprocity and a mother/offspring relationship were the strongest predictors of whether or not an individual shared meat. ConclusionsThe results of this study emphasize the complexity of chimpanzee meat sharing behaviors, especially at a site where social tolerance offers increased opportunities for meat sharing by individuals other than dominant males. These findings can be placed in a referential model to inform hypotheses about the sensitivity of food sharing to environmental pressures, such as resource scarcity in savanna landscapes.
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- Award ID(s):
- 2022314
- PAR ID:
- 10556951
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- American Journal of Biological Anthropology
- Volume:
- 182
- Issue:
- 2
- ISSN:
- 2692-7691
- Page Range / eLocation ID:
- 224 to 236
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/ajpa.24815
