Impartial Institutions, Pathogen Stress and the Expanding Social Network

Abstract

Anthropologists have documented substantial cross-society variation in people's willingness to treat strangers with impartial, universal norms versus favoring members of their local community. Researchers have proposed several adaptive accounts for these differences. One variant of the pathogen stress hypothesis predicts that people will be more likely to favor local in-group members when they are under greater infectious disease threat. The material security hypothesis instead proposes that institutions that permit people to meet their basic needs through impartial interactions with strangers reinforce a tendency toward impartiality, whereas people lacking such institutions must rely on local community members to meet their basic needs. Some studies have examined these hypotheses using self-reported preferences, but not with behavioral measures. We conducted behavioral experiments in eight diverse societies that measure individuals' willingness to favor in-group members by ignoring an impartial rule. Consistent with the material security hypothesis, members of societies enjoying better-quality government services and food security show a stronger preference for following an impartial rule over investing in their local in-group. Our data show no support for the pathogen stress hypothesis as applied to favoring in-groups and instead suggest that favoring in-group members more closely reflects a general adaptive fit with social institutions that have arisen in each society.

Innovation in the collective brain

“…As cross-cultural research reveals, collective brains also differ in the psychology of their constituent cultural brains. For example, some societies have a higher level of xenophobia [65] with potential implications for the inflow of ideas from outgroups. Societies also differ in 'tightness' and 'looseness' [66]-their openness to divergent ideas-with consequent effects for cultural variance [67].…”

The Evolution of Culture and Institutions: Evidence from the Kuba Kingdom

“…Hruschka et al (2014) use variation in public good provision on the national level as the explanatory variable. They also recognize the possibility of co-evolution between their variables of interest and so are therefore interested in estimating the correlation between the two measures without necessarily imposing a causal interpretation.…”

Moralistic gods, supernatural punishment and the expansion of human sociality

“…To measure favouritism towards oneself and local community under maximally anonymous conditions, we modified the random allocation game 9,28,29 . In this game (Fig.…”

“…Using sites as fixed effects allows us to remove the variation between our sites, so the results in Table 2 only capture the differences among individuals within sites. Based on previous work 9, 29 , we suspected that material insecurity and number of children would increase self and local favouritism, and therefore we include both in our model (Supplementary Information section S2.3.1). To affirm the robustness of these analyses, we estimated many alternative models, formulated mixed models, and used both alternative standard error estimates and different approaches to modelling the error (Supplementary Information section S5.4).…”