An ancient trait creates political leaningsHUMANS, like other animals, have evolved to notice and avoid sources of infection, whether that be rotten food or sickly members of their own species. This “behavioural immune system” can have unexpected consequences. Studies have, for instance, shown that those whose noses are more easily offended are also more likely to shun foreigners or disapprove of homosexuals. More broadly, people who live in regions with more to fear from pathogens tend to be less promiscuous and gregarious (such risky behaviour may spread disease)... This led Marco Liuzza of the Magna Graecia University of Catanzaro, in Italy, and his colleagues to wonder whether there might be a link between a person’s sensitivity to malodorousness and the likelihood of them being sympathetic to right-wing authoritarian views... The researchers found that those scoring highly on the BODS scale did indeed hold more authoritarian views. They found no such correlation between the BODS score and more broadly conservative opinions... he effect was small, enough to explain between 4% and 16% of the difference in viewpoints (family background, economic circumstances and other factors would presumably account for much of the rest)... prejudices and political views can be influenced by a person’s desire to avoid disease and bad smells.