Disgusting Ultimatums

March 2, 2009

CBC radio’s Quirks and Quarks show had a segment on the disgust response. One of the experiments demonstrates that people playing the ultimatum game show the facial disgust response when they receive a low offer that they ultimately reject. From a press release:

“Morality is often pointed to as the pinnacle of human evolution and development,” says lead author Hanah Chapman, a graduate student in the Department of Psychology.  “However, disgust is an ancient and rather primitive emotion which played a key evolutionary role in survival.  Our research shows the involvement of disgust in morality, suggesting that moral judgment may depend as much on simple emotional processes as on complex thought.” The research is being published in Science on February 27, 2009. 

This is why I found the research on chimps playing the ultimatum game with raisins so fascinating. Chimps play the way rational economists play (they accept any amount) while humans reject unfair offers on moral grounds. 

This adds to the work of Dan Kelly who believes the human moral system has co-opted the disgust system.