Cooperation through Image Scoring in Humans

• Published in: Science (American Association for the Advancement of Science) Vol. 288; no. 5467; pp. 850 - 852
• Main Authors: Wedekind, Claus, Milinski, Manfred
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for the Advancement of Science 05.05.2000; American Association for the Advancement of Science; The American Association for the Advancement of Science
• Subjects: Altruism; Altruism (Human behavior); Behavior; Biological and medical sciences; Biological invasions; Clouds; Computer Simulation; Cooperative Behavior; Cooperativeness; Donors; Ecological invasion; Evolution; Fundamental and applied biological sciences. Psychology; Games, Experimental; Humans; Hurricanes; Microwaves; Oceans; Psychology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Scoring; Skin temperature; Social Behavior; Social groups; Social interactions. Communication. Group processes; Social Perception; Social psychology; Species; Species diversity; Statistical Analysis; Storms; United States; Human; Social interaction; Game theory; Cooperation
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.288.5467.850

The "tragedy of the commons," that is, the selfish exploitation of resources in the public domain, is a reason for many of our everyday social conflicts. However, humans are often more helpful to others than evolutionary theory would predict, unless indirect reciprocity takes place and is based on image scoring (which reflects the way an individual is viewed by a group), as recently shown by game theorists. We tested this idea under conditions that control for confounding factors. Donations were more frequent to receivers who had been generous to others in earlier interactions. This shows that image scoring promotes cooperative behavior in situations where direct reciprocity is unlikely.