OHN HIBBING used to be a traditional political scientist. He studied elections, ran opinion polls and researched why some politicians opt to retire rather than wait around to be defeated by challengers. "About as traditional as it gets," he says.Roughly a decade ago, though, Hibbing shifted to a new approach that is starting to revolutionise how we think about politics. He began to explore whether political preferences might be partly based in biology. The idea initially met with great scepticism from his peers. But Hibbing and his collaborators at the Political Physiology Lab at the University of Nebraska-Lincoln now have a stack of scientific publications backing the idea.