Influence of network structure on cooperative dynamics in coupled socio-ecological systems

Interactions in real-world social and biological organizations are complex. Spatial structures or social networks enable clusters of cooperators to outcompete defectors when the altruistic act of a cooperator benefits only its neighbors. In this context, it had been shown that cooperation is favored if the benefit-to-cost ratio of the altruistic act exceeds the average number of interactions. This implies that cooperation survives better in societies with less social ties. For coupled socio-ecological systems in which an unselfish act is assumed to benefit all users who have open access to the resource, we show that when social sanction is present, the opposite can happen: cooperation can be easily promoted in populations where virtually everyone knows everyone else but not in populations that possess fewer connections