Playing against the fittest: A simple strategy that promotes the emergence of cooperation

TL;DR

This paper demonstrates that biasing interactions towards more successful neighbors significantly promotes the emergence and stability of cooperation in evolutionary game networks, expanding the conditions under which cooperation can thrive.

Contribution

It introduces and analyzes a simple neighbor selection strategy that favors more successful agents, showing its effectiveness and stability in promoting cooperation.

Findings

Bias towards more successful neighbors expands cooperation survival range.

Selecting fitter neighbors can lead to cooperation dominance.

The strategy is evolutionarily stable and naturally emerges from randomness.

Abstract

Understanding the emergence and sustainability of cooperation is a fundamental problem in evolutionary biology and is frequently studied by the framework of evolutionary game theory. A very powerful mechanism to promote cooperation is network reciprocity, where the interaction patterns and opportunities for strategy spread of agents are constrained to limited sets of permanent interactions partners. Cooperation survives because it is possible for close-knit communities of cooperation to be shielded from invasion by defectors. Here we show that parameter ranges in which cooperation can survive are strongly expanded if game play on networks is skewed towards more frequent interactions with more successful neighbours. In particular, if agents exclusively select neighbors for game play that are more successful than themselves, cooperation can even dominate in situations in which it would die out if interaction neighbours were chosen without a bias or with a preference for less successful opponents. We demonstrate that the "selecting fitter neighbours" strategy is evolutionarily stable. Moreover, it will emerge as the dominant strategy out of an initially random population of agents.