The Coupling Effect between the Environment and Strategies Drives the Emergence of Group Cooperation

Abstract

Introducing environmental feedback into evolutionary game theory has led to the development of eco-evolutionary games, which have gained popularity due to their ability to capture the intricate interplay between the environment and decision-making processes. However, current research in this field relies on replicator equations, which limits the study to macroscopic evolutionary dynamics in infinite populations. In this study, we propose a multi-agent computational model based on reinforcement learning to explore the coupled dynamics between strategies and the environment in finite populations from a bottom-up perspective. Our findings indicate that even in environments that favor defectors, high levels of group cooperation can emerge from self-interested individuals, highlighting the significant role of the coupling effect between the environment and strategies. Over time, the higher payoff of defection can be diluted due to environmental degradation, while cooperation can become the dominant strategy when positively reinforced by the environment. Remarkably, individuals can accurately detect the inflection point of the environment solely through rewards, when a reinforcing positive feedback loop are triggered, resulting in a rapid increase in agents' rewards and facilitating the establishment and maintenance of group cooperation. Our research provides a fresh perspective on understanding the emergence of group cooperation and sheds light on the underlying mechanisms involving individuals and the environment.

Keywords: Emergence of cooperation，social dilemma，eco-evolutionary game