Positions on economic redistribution correlated with upper-body strength.
PROBLEM: The pre-societal, animal model of conflict resolution is simple, brutal, and effective. Leaving aside political gambles, moral considerations, and the like, the strong are more willing to fight for their self-interest, while the weak find it more advantageous not to assert themselves. Extrapolated to a fairly simple conflict of interest -- wealth redistribution -- do modern humans operate under the same logic?
METHODOLOGY: Researchers at Aarhus University in Denmark and UC Santa Barbara collected from several hundred men and women in Argentina, the U.S., and Denmark. They categorized the subjects by socioeconomic class, their upper-body strength, or "fighting ability" (as measured by the "circumference of the flexed bicep of the dominant arm"), and their responses to a questionnaire gauging their support for economic redistribution.
For the rest of the story: http://www.theatlantic.com/health/archive/2013/05/study-mens-biceps-predict-their-political-ideology/275942/