Evolution of cooperation with tag-based expulsion in spatial public goods game

We introduce tag-based expulsion and explore its dynamic influence on cooperative behavior within a spatial public goods game. Our model employs a multi-agent system where agents, characterized by their strategies and tags, participate in public goods games and expel neighbors with dissimilar tags. The expulsion process effectively reshapes the interaction structure, providing a protective shield for cooperative clusters against defector infiltration. We demonstrate that expulsion, tag mutability, and tolerance are pivotal in driving cooperation levels and the optimal interaction structure. Even in less favorable conditions characterized by low enhancement factors, cooperation can emerge given appropriate tolerance levels. Our research underscores the importance of moderate population density, tag-based expulsion, and well-calibrated expulsion intensity in fostering cooperation, introducing fresh perspectives on the interplay between social dynamics and evolutionary processes. Additionally, we provide evidence of the dynamic adaptability of expulsion mechanisms, suggesting they may be integral to understanding cooperation in various societal contexts. These findings open up new avenues for further exploration of the complexity of cooperative behaviors and the roles of expulsion mechanisms in the evolution of cooperation.