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Cited by 1Evolutionary Game Theory and CooperationEvolutionary Psychology and Human BehaviorSocial and Intergroup Psychology

The Evolutionary-Ecological Basis of Xenophilia

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Grueter, Cyril C.·2026·Human Nature
DOI 10.1007/s12110-026-09521-4PMC PMC13633140
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Abstract

Humans are uniquely adept at cultivating positive, xenophilic relationships beyond their immediate group, forming bonds through various mechanisms such as trade, exogamy, and shared defense. Despite the significance of intergroup cooperation, synthetic approaches to understanding the evolutionary, ecological, and institutional drivers of xenophilia remain underdeveloped compared to the wealth of research on intergroup conflict. Here, I synthesize ethnographic, archaeological, psychological and comparative evidence to argue that xenophilia is supported by recurrent human cognitive and social capacities whose expression and stability depend on ecological, economic and institutional contexts. The aims of this paper are threefold: first, to clarify the selective pressures and incentives that favour peaceful intergroup relations, with particular attention to factors contributing to amicable intergroup ties and expanding the circle of tolerance and cooperation, including economic interdependence through trade and reciprocity, information exchange, exogamy, and the necessity of collective defense against external threats; second, to examine how these different drivers of xenophilia interact and under what conditions they generate, stabilize or fail to sustain intergroup tolerance; and third, to place human xenophilia in comparative perspective by highlighting both parallels and distinctions with non-human primates in their strategies for fostering intergroup peace. By distinguishing between mechanisms that generate cooperation and those that stabilize it in the face of freeriding and defection, this synthesis highlights how humans uniquely scale and institutionalize intergroup peace. This perspective is particularly timely, as uncovering the evolutionary roots of tolerance and cooperation across group boundaries remains crucial for addressing pressing global challenges such as climate change, poverty, famine, conflict, and disease.

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  • Given the prehistorical data, however incomplete it is, there is evidence of inter-group exchange and cooperation.

    “Given the prehistorical data, however incomplete it is, there is evidence of inter-group exchange and cooperation (Glowacki, 2024;Grueter, 2026)”

    From Durkheim, Indoctrinability and the Moral Ambivalence of Human Sociality (2026) · cites this paper as Grueter, 2026

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Cited by

Sorted by citations

Authors
Grueter, C. C.
Affiliations
The University of Western Australia (AU)
Corresponding author
Grueter, Cyril C.
ORCID
Grueter, Cyril C.
Venue
Human Nature
Publisher
Springer Science and Business Media LLC
Published
2026-05-04
Volume
37
Issue
3
Pages
215-240
ISSN
  • 1045-6767 (ISSN-L)
  • 1936-4776
DOI
10.1007/s12110-026-09521-4
PMC
PMC13633140
OpenAlex
W7160193603
Cited by
1
References
9
Citations by year
2026: 1
FWCI
11.38
Type
journal article
Language
en
Open access
Licence
Locations
  • Human Nature (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
Topics
  • Social Sciences › Sociology and Political Science › Evolutionary Game Theory and Cooperation
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Evolutionary Psychology and Human Behavior
  • Social Sciences › Sociology and Political Science › Social and Intergroup Psychology
Keywords
xenophilia, intergroup cooperation, intergroup tolerance, trade, reciprocity, exogamy, collective defense, free-riding, defection, non-human primates, evolutionary ecology, institutionalization of cooperation, information sharing
MeSH terms
Animals, Cooperative Behavior, Biological Evolution, Humans, Primates, Social Behavior

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