©john wiley & sons, inc. 2007 huffman: psychology in action (8e) evolution of cooperation: why...
TRANSCRIPT
©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)
Evolution of cooperation: Why make friends?
Why be nice, making friends must have offered some fitness advantage for our ancestors
• Evolution of niceness:– Kin selection: being nice to those
with similar genetics – William Hamilton: inclusive fitness
©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)
Kin selection
• There are a number of examples of what appear to be altruistic behaviors among animals. Most are explainable as examples of kin selection.
©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)
Reciprocity: You scratch my back I’ll scratch yours
• Robert Trivers: Reciprocal Altruism• Non related individuals
sometimes engage in reciprocal arrangements, vampire bats share blood, chimps groom for food
©John Wiley & Sons, Inc. 2007 Huffman: Psychology in Action (8e)
Indirect reciprocity: being nice to the nice
• Richard Alexander: Fitness benefits of a good reputation• Some animals are sensitive to reputation and restrict
reciprocal interactions to only those who have a history of playing fair
Strong reciprocity: Upholding social norms
• Resurrection of group selection: Groups with more cooperative norms more likely to survive then those without.
• Evidence– People uphold social norms even a personal cost (ultimatum games)– Bias toward kin is a group-based form of selection– Evidence of group competition in ancestral past– “leveling” effects of “punishment at a distance” Paul Bingham’s “stoning”
hypothesisMajor figures: Herb Gintis, David Sloan Wilson and others
Prisoner’s Dilemma
• A “game” that pits defensive self-interest against cooperative tendencies. Used in lab studies of the evolution of cooperation.
• Asks question: When will self-interested agents risk cooperation in order to achieve a greater payoff.
When can cooperative strategies evolve? When does cooperation have higher fitness than selfishness?
• Tit for tat or direct reciprocity
• Forgiveness• Indirect
reciprocity• Spatial selection• Multi-level
selection
Tragedy of the Commons
Avoiding the Tragedy
• Factors that increase cooperation on use of common “goods”
• 1. Authoritative information on the state of the resource• 2. Public generosity (reputation)• 3. Being watched