Scale-free networks provide a unifying framework for the emergence of cooperation.

  title={Scale-free networks provide a unifying framework for the emergence of cooperation.},
  author={Francisco C. Santos and Jorge M. Pacheco},
  journal={Physical review letters},
  volume={95 9},
We study the evolution of cooperation in the framework of evolutionary game theory, adopting the prisoner's dilemma and snowdrift game as metaphors of cooperation between unrelated individuals. In sharp contrast with previous results we find that, whenever individuals interact following networks of contacts generated via growth and preferential attachment, leading to strong correlations between individuals, cooperation becomes the dominating trait throughout the entire range of parameters of… 

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