Temperature, cultural masculinity and domestic political violence : a cross-national study.

Cross-national data sets were used to examine the association between ambient temperature and internal political voilence in 136 countries between 1948 and 1977. Political riots and armed attacks occur more frequently in warm countries than in both cold and hot countries, after effects of population size, surface area, and levels of socio-economic development and democracy are controlled. National differences on the cultural masculinity dimensions, do account for this curvilinear temperature-violence association, in a subsample of 53 countries suggesting that culture mediates the association. An explanation for this mediation in terms of the paternal investment theory is proposed.