What's in it for me? Self-regard precludes altruism and spite in chimpanzees.
Sensitivity to fairness may influence whether individuals choose to engage in acts that are mutually beneficial, selfish, altruistic, or spiteful. In a series of three experiments, chimpanzees (Pan troglodytes) could pull a rope to access out-of-reach food while concomitantly pulling another piece of food further away. In the first study, they could make a choice that solely benefited themselves (selfishness), or both themselves and another chimpanzee (mutualism). In the next two experiments, they could choose between providing food solely for another chimpanzee (altruism), or for neither while preventing the other chimpanzee from receiving a benefit (spite). The main result across all studies was that chimpanzees made their choices based solely on personal gain, with no regard for the outcomes of a conspecific. These results raise questions about the origins of human cooperative behaviour.
Jensen
Keith
K
The Max Planck Institute for Evolutionary Anthropology, Department of Developmental and Comparative Psychology, Deutscher Platz 6, 04103 Leipzig, Germany. jensen@eva.mpg.de
Hare
Brian
B
Call
Josep
J
Tomasello
Michael
M
D000533:Altruism; D000818:Animals; D001522:Behavior, Animal; D002755:Choice Behavior; D003163:Competitive Behavior; D003299:Cooperative Behavior; D009042:Motivation; D002679:Pan troglodytes / Q000235:genetics / Q000502:physiology*