ArticlePloS one2021
Uniting against a common enemy: Perceived outgroup threat elicits ingroup cohesion in chimpanzees.
Article in PloS one, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
12 citing papers in PubMed.
- Mammals tolerate harmless human presence: Lessons from COVID-19 lockdown on Barro Colorado Island, Panamá.Scientific reports · 2026Article
- Review
- Chimpanzee groups achieve sustainable resource use in a common-pool resource dilemma.Communications psychology · 2026Article
- Spatial and Temporal Determinants of Anxiety in a Wild Arboreal Primate.Ecology and evolution · 2025Article
- Response to collective threat: Russian invasion unifies Ukrainians across ethnic, linguistic, religious and geographic lines.Royal Society open science · 2025Article
- Oxytocin homogenizes horse group organization.iScience · 2024Article
- Increased alertness and moderate ingroup cohesion in bonobos' response to outgroup cues.PloS one · 2024Article
- Leader-follower behavioural coordination and neural synchronization during intergroup conflict.Nature human behaviour · 2023Article
- Exploring the Influence of Perceived Ingroup and Outgroup Threat on Quality of Life in a Region Impacted by Protracted Conflict.International journal of environmental research and public health · 2023Article
- Parochial cooperation in wild chimpanzees: a model to explain the evolution of parochial altruism.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2022Review
- The dynamics of social cohesion in response to simulated intergroup conflict in banded mongooses.Ecology and evolution · 2021Article
- The founder sociality hypothesis.Ecology and evolution · 2021Article
Corrections and comments
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Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Outgroup threat has been identified as an important driver of ingroup cohesion in humans, but the evolutionary origin of such a relationship is unclear. Chimpanzees (Pan troglodytes) in the wild are notably aggressive towards outgroup members but coordinate complex behaviors with many individuals in group hunting and border patrols. One hypothesis claims that these behaviors evolve alongside one another, where outgroup threat selects for ingroup cohesion and group coordination. To test this hypothesis, 5 groups of chimpanzees (N = 29 individuals) were observed after hearing either pant-hoots of unfamiliar wild chimpanzees or control crow vocalizations both in their typical daily environment and in a context of induced feeding competition. We observed a behavioral pattern that was consistent both with increased stress and vigilance (self-directed behaviors increased, play decreased, rest decreased) and increased ingroup cohesion (interindividual proximity decreased, aggression over food decreased, and play during feeding competition increased). These results support the hypothesis that outgroup threat elicits ingroup tolerance in chimpanzees. This suggests that in chimpanzees, like humans, competition between groups fosters group cohesion.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.