Reductions in the prevalence of infectious disease are associated with increases in gender equality in the United States and the United Kingdom over the past several decades, reports a paper published online this week in the new journal Nature Human Behaviour. The study suggests that efforts to reduce infectious diseases, such as vaccinations, free health care, public sanitation and water treatment, might increase equality between the sexes around the globe.
Although differences in gender equality between societies and changes within them have been well documented, the causes of shifts in levels of gender equality remain poorly understood.
Michael Varnum and Igor Grossman use archival data from 1951-2013 in the United States and from 1945-2014 in the United Kingdom to examine the effect of four key ecological dimensions - infectious disease, resource scarcity, warfare and climatic stress - on changes in gender equality over time. They find that, among the variables examined, pathogen prevalence shows the strongest association with gender inequality. In both countries, changes in pathogen prevalence preceded changes in gender inequality, suggesting a possible causal relationship. They find that more broadly traditional cultural norms and attitudes did not account for the link between pathogens and gender inequality, but that life history strategies significantly mediated the effect of pathogens on gender inequality. That is, when levels of infectious disease are low, people are more likely to adopt slower life history strategies. For women this might mean delaying reproduction in favour of pursuing education and careers.
The authors note that, although their analysis does not enable definite inferences concerning causality, it still suggests a crucial role for pathogen prevalence.