We usually think of global discord in terms of East vs. West—or, more recently, North vs. South. But new research points to a different geographical pattern that better predicts which societies are liberal and tolerant, and which are not: Their distance from the equator.
"Conflict culture differs more between Northerners and Southerners, and oppositely so above and below the equator," write psychologists Evert Van de Vliert of the University of Groningen and Lucian Conway III of the University of Montana.
Ethnocentrism, political oppression, and media censorship "are all less prevalent among Northerners than among Southerners in the Northern Hemisphere," they report, "but more prevalent among Northerners than Southerners in the Southern Hemisphere."
Writing in the journal Negotiation and Conflict Management Research, the researchers looked at cultural norms in 80 countries around the world. They used a variety of measures, including the extent to which outsiders are derogated, the level of political oppression, whether sexual minorities are discriminated against, whether the death penalty is used, and whether the press is regularly attacked and/or censored.
Taking all that into account, they found that societies were, on average, more open and tolerant the closer they were to either the North or South Pole.
Why would this be? Van de Vliert and Conway note that, in terms of livability, nations near the equator experience fundamentally different challenges than those nearer to the polls. "These ecological differences can help clarify why, where, and how a habitat's inhabitants evolve distinct habits of conflict management," they write.
Specifically, the researchers argue that different cultural norms developed in relation to the unique ecological challenges faced by nations at different latitudes.
Van de Vliert and Conway report that "thermal stress"—the need to adapt to inhospitable temperatures—plays a major but disguised role, exerting its impact via its effect on the availability of water, and via the poverty it promotes (by making life so difficult for subsistence farmers, among others).
"Conflict culture flourishes where thermal stress and subsistence stress are both high," they report.
It's worth noting that people in warm—and especially tropical—climates are traditionally at greater risk from pathogens such as harmful microorganisms. Other researchers have argued this could be one root cause of more-closed societies and fear of outsiders, who could be bringing disease.
The results support a prediction made by the Enlightenment political philosopher Montesquieu, who argued the culture of a country is influenced by climate and geography—and that regional differences noted in the Northern Hemisphere should logically be reversed in the Southern Hemisphere.
It appears his intuition was spot on. This latest research suggests that people who live at a certain latitude are less likely to give outsiders or minorities much latitude of their own.