A new scientific paper suggests our partisan divide may come from biology and genetics.
Mother Jones highlights a study from John Hibbing at the University of Nebraska. Hibbing argues that political conservatives have a “negativity bias.” That means they are more prone to react to threats in their environment than liberals.
In the process, Hibbing et al. marshal a large body of evidence, including their own experiments using eye trackers and other devices to measure the involuntary responses of political partisans to different types of images. One finding? That conservatives respond much more rapidly to threatening and aversive stimuli (for instance, images of “a very large spider on the face of a frightened person, a dazed individual with a bloody face, and an open wound with maggots in it,” as one of their papers put it).
In other words, the conservative ideology, and especially one of its major facets—centered on a strong military, tough law enforcement, resistance to immigration, widespread availability of guns—would seem well tailored for an underlying, threat-oriented biology.
The authors go on to speculate that this ultimately reflects an evolutionary imperative. “One possibility,” they write, “is that a strong negativity bias was extremely useful in the Pleistocene,” when it would have been super-helpful in preventing you from getting killed.