Understanding Effects of Pathogens

The prevalence of pathogens historically shows effects on cultures and how they behave amongst others. Pathogens are associated with the risk of infectious diseases, causing societies to be more trustful of what they know, and weary towards what they do not know. As a result, cultures are more likely to be "tight" and showcase more in-group bias.

What is a tight culture? Society where social norms are rigid, similar to one another, emphasized, and subject to conformity.
What is in-group bias? Favoring those who are more like you, who are in your social group, have similar characteristics, and seem closely related.

These characteristics of a society reflect that of the major defining elements of authoritarian contexts.

TIGHTNESS: This quote from the article "Pathogens and Politics: Further Evidence That Parasite Prevalence Predicts Authoritarianism" really showcases how threats of pathogens can influence communities to adhere to social norms, conform, stay together, and reflect that of a tight culture to avoid infectious disease, being seen as dangerous to others, outcasted, or looked down at by their societal context.

This chart from Gelfand et al., shows us evidence from the hypothesis shown above, that the historical prevalence of pathogens was existent throughout more tight cultures, who adhered to social homogenity based on this research of 33 nations.

IN-GROUP BIAS: This source accounts for the understanding of high-parasite stress amongst group dynamics. While the behavioral immune system establishes ancestrally compromised beliefs about in-group and out-group, viewing out-group individuals with caution as more unhealthy to prevent infectious disease, this text describes how host parasite races are geographically localized across the range of host species, leading to a co-evolutionary idea that people inhabiting a certain area have adaptations to avoid the parasites. Further, out-groups may harbor novel parasites that cannot be defended against by the similar in-group's adaptations- leading to these elements of xenophobia, discrimination, bias, or ethnocentrism.

This summary of the research from Fincher and Thornhill outlines that amongst world regions, when considering the correlation between the dependent variables and combined parasite-stress at the world regional level, all the correlations were positive and in the direction predicted by the parasite stress theory- asserting universality of in-group bias with reference to family ties, connectivity, religiosity, and assortativeness, when pathogens are prevalent throughout cultures.