Evolutionary game selection creates cooperative environments

TL;DR

The paper addresses how cooperative behavior emerges when both strategies and the surrounding game environment coevolve, rather than assuming a fixed game. It introduces a coevolutionary framework where players carry payoff matrices parameterized by $(T_i,S_i)$ from the game diamond, with boundaries set by inequalities and parameters $\alpha=4$ and $\beta=2$, and analyzes dynamics on well-mixed and networked populations. It demonstrates that coevolution can foster cooperative environments and that network topology, especially heterogeneity and clustering, amplifies pro-social behavior; it links micro-level interactions to macro-level social dilemmas. The framework provides a mechanism to understand the origin of social dilemmas in real-world populations and offers a path to study environment-strategy coevolution in complex systems.

Abstract

The emergence of collective cooperation in competitive environments is a well-known phenomenon in biology, economics, and social systems. While most evolutionary game models focus on the evolution of strategies for a fixed game, how strategic decisions coevolve with the environment has so far mostly been overlooked. Here, we consider a game selection model where not only the strategies but also the game can change over time following evolutionary principles. Our results show that coevolutionary dynamics of games and strategies can induce novel collective phenomena, fostering the emergence of cooperative environments. When the model is taken on structured populations the architecture of the interaction network can significantly amplify pro-social behavior, with a critical role played by network heterogeneity and the presence of clustered groups of similar players, distinctive features observed in real-world populations. By unveiling the link between the evolution of strategies and games for different structured populations, our model sheds new light on the origin of social dilemmas ubiquitously observed in real-world social systems.

Figures (1)

• Figure 1: Games classification. Each player is assigned one pair of values ($T_i, S_i)$ from the game diamond. The equations for the boundaries of each game are derived from the inequalities between the payoffs. Here we set $\alpha = 4$, and $\beta=2$.