Ratings

This is a study showing that in social systems, cooperation levels do not only depend on global connectivity properties, but more radically on the topological properties of the system at the mesoscopic scale, the so-called communities. As these structures are abundant in social and biological systems, where the emergence of cooperation is most relevant, the present study represents an important step in our current understanding of the survival and robustness of social cooperation.

What I believe is the most relevant contibution of this article is to illustrate that the dynamic behavior in a network depends crucially on its community structure and that typical parameters commonly employed to characterize networks may be unable to distinguish between lattices with different global behavior. This is an important step in our understanding of complex networks.

In the last years we have seen how important are the topological properties of the connectivity patterns in the dynamical evolution of complex systems. In particular, the authors analyze the effect of the intermediate scales (mesoscales) in the emergence of cooperation on social networks. Considering that the dynamics, as well as the network, are well justified in empirical grounds it represents a clear advence in that subject.