Coevolution of Cooperation and Partner Rewiring Range in Spatial Social Networks

TL;DR

This paper investigates how spatially embedded social networks influence the coevolution of cooperation and partner rewiring preferences, revealing that global rewiring can promote cooperation and lead to small-world network structures.

Contribution

It introduces a coevolutionary model considering geographic distance in partner rewiring, highlighting the emergence of small-world networks and cooperation under certain conditions.

Findings

Global rewiring can coevolve with cooperation.

Networks exhibit small-world properties with high clustering.

Optimal reputation information enhances global cooperation.

Abstract

In recent years, there has been growing interest in the study of coevolutionary games on networks. Despite much progress, little attention has been paid to spatially embedded networks, where the underlying geographic distance, rather than the graph distance, is an important and relevant aspect of the partner rewiring process. It thus remains largely unclear how individual partner rewiring range preference, local vs. global, emerges and affects cooperation. Here we explicitly address this issue using a coevolutionary model of cooperation and partner rewiring range preference in spatially embedded social networks. In contrast to local rewiring, global rewiring has no distance restriction but incurs a one-time cost upon establishing any long range link. We find that under a wide range of model parameters, global partner switching preference can coevolve with cooperation. Moreover, the resulting partner network is highly degree-heterogeneous with small average shortest path length while maintaining high clustering, thereby possessing small-world properties. We also discover an optimum availability of reputation information for the emergence of global cooperators, who form distant partnerships at a cost to themselves. From the coevolutionary perspective, our work may help explain the ubiquity of small-world topologies arising alongside cooperation in the real world.