Vacancies in growing habitats promote the evolution of cooperation

We study evolutionary game dynamics in a growing habitat with vacancies. Fitness is determined by the global effect of the environment and a local prisoner's dilemma among neighbors. We study population growth on a one-dimensional lattice and analyze how the environment affects evolutionary competition. As the environment becomes harsh, an absorbing phase transition from growing populations to extinction occurs. The transition point depends on which strategies are present in the population. In particular, we find a 'cooperative window' in parameter space, where only cooperators can survive. A mutant defector in a cooperative community might briefly proliferate, but over time naturally occurring vacancies separate cooperators from defectors, thereby driving defectors to extinction. Our model reveals that vacancies provide a strong boost for cooperation by spatial selection.

Automated summary

In this study, we investigate the impact of the environment on evolutionary competition in a growing habitat with vacancies using evolutionary game dynamics. We find that as the environment becomes harsh, a transition from growing populations to extinction occurs. The occurrence of this transition point depends on the strategies present in the population. Interestingly, we observe a 'cooperative window' where only cooperators can survive. Furthermore, vacancies provide spatial selection and enhance cooperation.