Parasites, democratization, and the liberalization of values across contemporary countries

Abstract

The countries of the world vary in their position along the autocracy-democracy continuum of values. Traditionally, scholars explain this variation as based on resource distribution and disparity among nations. We provide a different framework for understanding the autocracy-democracy dimension and related value dimensions, one that is complementary (not alternative) to the research tradition, but more encompassing, involving both evolutionary (ultimate) and proximate causation of the values. We hypothesize that the variation in values pertaining to autocracy-democracy arises fundamentally out of human (Homo sapiens) species-typical psychological adaptation that manifests contingently, producing values and associated behaviours that functioned adaptively in human evolutionary history to cope with local levels of infectious diseases. We test this parasite hypothesis of democratization using publicly available data measuring democratization, collectivism-individualism, gender egalitarianism, property rights, sexual restrictiveness, and parasite prevalence across many countries of the world. Parasite prevalence across countries is based on a validated index of the severity of 22 important human diseases. We show that, as the hypothesis predicts, collectivism (hence, conservatism), autocracy, women's subordination relative to men's status, and women's sexual restrictiveness are values that positively covary, and that correspond with high prevalence of infectious disease. Apparently, the psychology of xenophobia and ethnocentrism links these values to avoidance and management of parasites. Also as predicted, we show that the antipoles of each of the above values--individualism (hence, liberalism), democracy, and women's rights, freedom and increased participation in casual sex--are a positively covarying set of values in countries with relatively low parasite stress. Beyond the cross-national support for the parasite hypothesis of democratization, it is consistent with the geographic location at high latitudes (and hence reduced parasite stress) of the early democratic transitions in Britain, France and the U.S.A. It, too, is consistent with the marked increase in the liberalization of social values in the West in the 1950s and 1960s (in part, the sexual revolution), regions that, a generation or two earlier, experienced dramatically reduced infectious diseases as a result of antibiotics, vaccinations, food- and water-safety practices, and increased sanitation. Moreover, we hypothesize that the generation and diffusion of innovations (in thought, action and technology) within and among regions, which is associated positively with democratization, is causally related to parasite stress. Finally, we hypothesize that past selection in the context of morbidity and mortality resulting from parasitic disease crafted many of the aspects of social psychology unique to humans.

Moral concerns across the United States: associations with life-history variables, pathogen prevalence, urbanization, cognitive ability, and social class

“…Pathogen prevalence -how much exposure a society has had to infectious diseases -is positively correlated with culture-level measures of authoritarianism (Murray, Schaller, & Suedfeld, 2013), religious diversity , collectivism (Fincher, Thornhill, Murray, & Schaller, 2008), and conformity (Murray, Trudeau, & Schaller, 2011), whereas it is negatively correlated with democracy (Thornhill, Fincher, & Aran, 2009), sociosexuality, extraversion, and openness to experience .…”

Parasite stress promotes homicide and child maltreatment

“…The benefits of out-group interactions include gains through intergroup trade, new and better ideas, and larger and more diversified social networks for marriage, reciprocity and other social alliances. Hence, openness towards out-groups and pursuit of out-group interactions and alliances are predicted to be strongly held values in regions of low parasite stress [8,15,23]. As mentioned, according to the parasite-stress theory, the embeddedness in in-group members that characterizes ethnocentrism functions in managing the local disease effects under high parasite stress.…”

“…Neophobia reduces contact with people with non-local norms and values, and thereby the novel infectious diseases they may harbour. Thus, xenophobia, ethnocentrism, philopatry and neophobia-elements of in-group assortative sociality-are predicted to be strongly held values in regions of high parasite stress [8,15,23].…”

“…Cultural behaviour in humans is a category of behavioural and psychological plasticity that evolved, at least in part, as a solution to the evolutionary historical fitness problem of local social complexity and change [32 -34]. We have argued that a significant part of this complexity and change arose from local people's adjustments in in-group and out-group-oriented behaviour to deal adaptively with temporally varying parasite problems [23].…”

“…of a conditional strategy with multiple contingent tactics [8,15,23]). Such plasticity in traits is favoured when phenotypic change allows the individual to modify its phenotypic expression in directions that give higher inclusive fitness than that achieved by a single phenotype.…”