Hunting for wealthy encounters promotes cooperation in spatial Prisoner’s Dilemma games
1 Center for Complex Systems, Department of Automatic Control Engineering, Xidian University, Xi’an 710071, P.R. China
2 Center for Systems and Control, State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing 100871, P.R. China
Received: 26 December 2012
Published online: 15 April 2013
We consider an evolutionary Prisoner’s Dilemma game on the lattice where a parameter α is employed to determine with whom individuals aspire to interact in future iterations. Specifically, for positive α, rich environments are preferentially considered when individuals hunt for new surroundings, while for negative α, the opposite holds. When α = 0, individuals adopt ‘random move’-like migration. The results indicate that aspiring for wealthy ambience makes cooperation survive and even thrive under certain circumstances. Moreover, there exist the optimal population densities that most uphold cooperation. We also investigate the expansion of cooperators. And the discovery of utmost salience is that cooperators can spontaneously break out for the population consisting of full defectors in the presence of strategy mutation. Our results relax the requirements for cooperation to outbreak and suggest that spying into others’ strategies is not always necessary for the cooperation to burst. Finally, we deepen our studies by exploring the situation that each individual has an independent α and find that the fate of evolution is mainly determined by the population composition in this scenario.
Key words: Statistical and Nonlinear Physics
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2013