Steven Crane Compiled Section Handouts. Human Behavioral Biology 2012

The individual has close friends of that race

You try to discern the person as an individual (does this person like Coke or Pepsi?) instead of as a member of a group (is this person older or younger than 30)

What does game theory have to say about aggression and cooperation?

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  The Nash Equilibrium following a Tragedy of the Commons situation would predict that everybody defects all the time for maximal gain.
  
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  But we do get cooperation, and it can pay off well (tit for tat, forgiving tit for tat, etc).
  

How does that cooperation get started?

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  Kin selection with the founder effect is the big theory here. Or just normal kin selection without isolation.
  
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  What eight other mechanisms foster cooperation?
  
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    Repeated interactions
    
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    An unknown number of rounds (not a finite set number)
    
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    Reputation/open-book play
    

  • Pairs playing multiple games at the same time (cooperation in one bleeds over to cooperation in another)

  • Altruistic punishment (policing - individuals can pay to punish cheaters)

  • Altruistic rewarding (individuals can pay to reward altruists)

  • Second-order punishment: punishing of non-punishers (like where you get punished if you fail to report somebody else's honor code violation)

  • Choice in who to play with

What's the take-home point on group selection?

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  It can exist in that groups of cooperators can outcompete groups of cheaters.
  
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  BUT that can have "good or bad" valence:
  
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    Cooperating groups might communally raise children and that's lovely.
    
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    Or cooperating groups might band together and exterminate neighboring groups (like with chimps). Not so lovely.
    

And what are those two crazy situations where cooperation is the last thing you'd expect, but you see it?

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