Infectious Diseases and the Evolution of Cross-Cultural Differences

W e’ll begin with a prediction: years from now it will become obvious to observe that cross-cultural differences result substantially from regional differences in the prevalence of infectious diseases. Does that sound presumptuous? Perhaps even preposterous? Maybe. For many readers, our prediction may seem like a provocation that we’ve made up out of thin air. That’s not quite so. The scientific literature has, for years, documented cultural differences that are predicted by the prevalence of pathogens (e.g., Gangestad & Buss, 1993; low, 1990; Quinlan, 2007; Sherman & Billing, 1999). But these findings tend to fly under the radar of the vast majority of social scientists who concern themselves with culture and cultural variation. Why has there been so little attention paid to the potentially profound role that infectious diseases might play in the creation of cross-cultural differences? One reason, perhaps, is that much cultural scholarship (e.g., cultural anthropology, cultural psychology) is concerned primarily with descriptions of cultural differences or with the consequences that these cultural differences have for individual behavior. less attention has been paid to the origins of cultural differences in the first place. another reason may lie in the fact that, in the occasional articles that do link pathogen prevalence to cultural outcomes, those outcomes have been relatively narrow in scope (pertaining specifically to food preparation, for instance, or to mating behavior). These findings may strike readers as interesting curiosities but perhaps not diagnostic of cultural differences more broadly. a third reason may be that there really hasn’t been much reason to expect that infectious diseases should have any sort of wide-ranging impact on culture. Only recently has there emerged a body of theory and research identifying specific psychological mechanisms that are responsive to the perceived threat of infectious diseases and that may play an important role in the construction of many different kinds of cross-cultural differences. With that context in mind, this chapter has three objectives.