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The global ecology of differentiation between us and them

Nature Human Behaviour volume 4, pages 270–278 (2020)Cite this article

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Abstract

Humans distinguish between we-groups and they-groups, such as relatives versus strangers and higher-ups versus lower-downs, thereby creating crucial preconditions for favouring their own groups while discriminating against others. Reported here is the finding that the extent of differentiation between us and them varies along latitude rather than longitude. In geographically isolated preindustrial societies, intergroup differentiation already peaked at the equator and tapered off towards the poles, while being negligibly related to longitude (observation study 1). Contemporary societies have evolved even stronger latitudinal gradients of intergroup differentiation (survey study 2 around 1970) and discrimination (mixed-method study 3 around 2010). The geography of contemporary differentiation and discrimination can be partially predicted by tropical climate stress (warm winters, hot summers and irregular rainfall), largely mediated by the interplay of pathogen stress and agricultural subsistence (explanatory study 4). The findings accumulate into an index of intergroup discrimination by inhabitants of 222 countries (integrative study 5).

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Fig. 1: Scatter plots and regression fit lines for the geography of intergroup differentiation in 90 preindustrial societies.
Fig. 2: Scatter plots and regression fit lines for the contemporary geography of intergroup differentiation and intergroup discrimination.
Fig. 3: Joint effects of pathogen stress and agricultural subsistence on intergroup differentiation in 52 societies around 1970 (R2 = 0.64).
Fig. 4: Joint effects of pathogen stress and agricultural subsistence on intergroup discrimination in 104 societies around 2010 (R2 = 0.56).

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Data availability

As indicated in the Methods, all data are available for visual inspection (Supplementary Information) and empirical analysis. SPSS data files for preindustrial and contemporary societies can be downloaded from https://hdl.handle.net/10411/YXI7WH. The author is prepared to provide clarifications if needed.

Code availability

The SPSS analysis scripts used in studies 1–5 are provided in the Supplementary Methods. The author is prepared to provide clarifications if needed.

References

  1. Tajfel, H. Human Groups and Social Categories (Cambridge Univ. Press, 1981).

  2. Triandis, H. C. Individualism and Collectivism (Westview, 1995).

  3. Hofstede, G. Culture’s Consequences: Comparing Values, Behaviors, Institutions, and Organizations Across Cultures (Sage, 2001).

  4. Alves, H., Koch, A. & Unkelbach, C. A cognitive–ecological explanation of intergroup biases. Psychol. Sci. 29, 1126–1133 (2018).

    Article  Google Scholar 

  5. Van de Vliert, E. Climato-economic origins of variation in ingroup favoritism. J. Cross Cult. Psychol. 42, 494–515 (2011).

    Article  Google Scholar 

  6. House, R. J., Hanges, P. J., Javidan, M., Dorfman, P. W. & Gupta, V. Culture, Leadership, and Organizations: The GLOBE Study of 62 Societies (Sage, 2004).

  7. Van de Vliert, E. & Postmes, T. Climato-economic livability predicts societal collectivism and political autocracy better than parasite stress does. Behav. Brain Sci. 35, 94–95 (2012).

    Article  Google Scholar 

  8. Van de Vliert, E. Climato-economic habitats support patterns of human needs, stresses, and freedoms. Behav. Brain Sci. 36, 465–521 (2013).

    Article  Google Scholar 

  9. Fincher, C. L. & Thornhill, R. Parasite stress promotes in-group assortative sociality: the cases of strong family ties and heightened religiosity. Behav. Brain Sci. 35, 61–79 (2012).

    Article  Google Scholar 

  10. Fincher, C. L., Thornhill, R., Murray, D. R. & Schaller, M. Pathogen prevalence predicts human cross-cultural variability in individualism/collectivism. Proc. R. Soc. B 275, 1279–1285 (2008).

    Article  Google Scholar 

  11. Talhelm, T. et al. Large-scale psychological differences within China explained by rice versus wheat agriculture. Science 344, 603–608 (2014).

    Article  CAS  Google Scholar 

  12. Talhelm, T., Zhang, X. & Oishi, S. Moving chairs in Starbucks: observational studies find rice–wheat cultural differences. Sci. Adv. 4, eaap8469 (2018).

    Article  Google Scholar 

  13. Van de Vliert, E. & Van Lange, P. A. M. Latitudinal psychology: an ecological perspective on creativity, aggression, happiness, and beyond. Perspect. Psychol. Sci. 14, 860–884 (2019).

    Article  Google Scholar 

  14. Tipps, D. C. Modernization theory and the comparative study of societies: a critical perspective. Comp. Stud. Soc. Hist. 15, 199–226 (1973).

    Article  Google Scholar 

  15. Inglehart, R. & Baker, W. E. Modernization, cultural change, and the persistence of traditional values. Am. Soc. Rev. 65, 19–51 (2000).

    Article  Google Scholar 

  16. Chown, S. L. & Gaston, K. J. Areas, cradles and museums: the latitudinal gradient in species richness. Trends Ecol. Evol. 15, 311–315 (2000).

    Article  CAS  Google Scholar 

  17. Harcourt, A. H. Humankind: How Biology and Geography Shape Human Diversity (Pegasus, 2015).

  18. Murdock, G. P. & White, D. R. Standard cross-cultural sample. Ethnology 8, 329–369 (1969).

    Article  Google Scholar 

  19. Murdock, G. P. & Wilson, S. F. Settlement patterns and community organization. Ethnology 11, 254–295 (1972).

    Article  Google Scholar 

  20. Ross, M. H. Political decision making and conflict: additional cross-cultural codes and scales. Ethnology 22, 169–192 (1983).

    Article  Google Scholar 

  21. Ross, H. M. The Culture of Conflict (Yale Univ. Press, 1993).

  22. Conway, L. G. III et al. Ecological origins of freedom: pathogens, heat stress, and frontier typography predict more vertical but less horizontal government restriction. Pers. Soc. Psychol. Bull. 43, 1378–1398 (2017).

    Article  Google Scholar 

  23. Hofstede, G. Culture’s Consequences: International Differences in Work-Related Values (Sage, 1980).

  24. Van Staveren, I., Webbink, E., De Haan, A. & Foa, R. The last mile in analyzing wellbeing and poverty: indices of social development. Forum Soc. Econ. 43, 8–26 (2014).

    Article  Google Scholar 

  25. Van Staveren, I. & Pervaiz, Z. Is it ethnic fractionalization or social exclusion, which affects social cohesion? Soc. Indic. Res. 130, 711–731 (2017).

    Article  Google Scholar 

  26. Van de Vliert, E. Climatic imprints on personality. Nat. Hum. Behav. 1, 864–865 (2017).

    Article  Google Scholar 

  27. Van de Vliert, E., Welzel, C., Shcherbak, A., Fischer, R. & Alexander, A. C. Got milk? Freedoms evolved from dairying climates. J. Cross Cult. Psychol. 49, 1048–1065 (2018).

    Article  Google Scholar 

  28. Parker, P. M. National Cultures of the World: A Statistical Reference (Greenwood Press, 1997).

  29. United Nations Development Programme Human Development Report 2004: Cultural Liberty in Today’s Diverse World (Oxford Univ. Press, 2004).

  30. United Nations Development Programme Human Development Report 2002: Deepening Democracy in a Fragmented World (Oxford Univ. Press, 2002).

  31. United Nations Development Programme Human Development Report 2006: Beyond Scarcity--Power, Poverty and the Global Water Crisis (Palgrave Macmillan, 2006).

  32. Nettle, D. Explaining global patterns of language diversity. J. Anthropol. Archaeol. 17, 354–374 (1998).

    Article  Google Scholar 

  33. Alesina, A., Devleeschauwer, A., Easterly, W., Kurlat, S. & Wacziarg, R. Fractionalization. J. Econ. Growth 8, 155–194 (2003).

    Article  Google Scholar 

  34. United Nations Development Programme. Human Development Indices and Indicators: 2018 Statistical Update (United Nations Development Programme, 2018).

  35. Sutin, A. R., Stephan, Y. & Terracciano, A. Perceived discrimination and personality development in adulthood. Dev. Psychol. 52, 155–163 (2016).

    Article  Google Scholar 

  36. Kruglanski, A. W. The Psychology of Closed Mindedness (Psychology Press, 2004).

  37. Hewstone, M., Rubin, M. & Willis, H. Intergroup bias. Annu. Rev. Psychol. 53, 575–604 (2002).

    Article  Google Scholar 

  38. Gebauer, J. E. et al. Cultural norm fulfillment, interpersonal belonging, or getting ahead? A large-scale cross-cultural test of three perspectives on the function of self-esteem. J. Pers. Soc. Psychol. 109, 526–548 (2015).

    Article  Google Scholar 

  39. Mischel, W. Toward a cognitive social learning reconceptualization of personality. Psychol. Rev. 80, 252–283 (1973).

    Article  CAS  Google Scholar 

  40. Diamond, J. Guns, Germs, and Steel: The Fates of Human Societies (W. W. Norton, 1997).

  41. Laitin, D. D., Moortgat, J. & Robinson, A. L. Geographic axes and the persistence of cultural diversity. Proc. Natl Acad. Sci. USA 109, 10263–10268 (2012).

    Article  CAS  Google Scholar 

  42. Van Lange, P. A. M., Rinderu, M. I. & Bushman, B. J. Aggression and violence around the world: a model of climate, aggression, and self-control in humans (CLASH). Behav. Brain Sci. 40, e75 (2017).

    Article  Google Scholar 

  43. Turchin, P., Adams, J. M. & Hall, T. D. East–west orientation of historical empires and modern states. J. World Syst. Res. 12, 219–229 (2006).

    Article  Google Scholar 

  44. Triandis, H. C. The self and social behavior in differing cultural contexts. Psychol. Rev. 96, 506–520 (1989).

    Article  Google Scholar 

  45. Gelfand, M. J. et al. Differences between tight and loose cultures: a 33-nation study. Science 332, 1100–1104 (2011).

    Article  CAS  Google Scholar 

  46. World Bank Atlas (World Bank, 1970).

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Acknowledgements

Helpful comments on drafts of this article were received from L. G. Conway, S. Daan, C. K. W. De Dreu, H. C. Santos, W. Scholl and P. A. M. Van Lange. The author received no specific funding for this work.

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Authors and Affiliations

  1. Faculty of Behavioural and Social Sciences, University of Groningen, Groningen, the Netherlands

    Evert Van de Vliert

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E.V.d.V. designed and performed the studies, analysed the data, and wrote and edited the manuscript.

Corresponding author

Correspondence to Evert Van de Vliert.

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The author declares no competing interests.

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Peer review information Primary handling editor: Aisha Bradshaw.

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Extended data

Extended Data Fig. 1 Joint effects of pathogen stress and agricultural subsistence on gender discrimination in 157 contemporary societies (R2 = .72).

Horizontally viewed, both slopes tell that higher pathogen stress increases gender discrimination, albeit less so in areas with much agriculture (B(153) = .29, p < .001, CI = .16 to .42 for the upper slope) than in areas with little agriculture (B(153) = .65, p < .001, CI = .49 to .82 for the lower slope). Vertically viewed, both gaps between slopes tell that more agriculture increases gender discrimination, albeit less so in areas with high pathogen stress (B(153) = .36, p < .001, CI = .22 to .49 for the right gap) than in areas with low pathogen stress (B(153) = .72, p < .001, CI = .56 to .89 for the left gap).

Supplementary information

Supplementary Information

Supplementary Methods and Supplementary Results for studies 1–5 and Supplementary Table 1 for study 1.

Reporting Summary

Supplementary Data 1

Supplementary data for studies 1–5.

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Van de Vliert, E. The global ecology of differentiation between us and them. Nat Hum Behav 4, 270–278 (2020). https://doi.org/10.1038/s41562-019-0783-3

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