Figure 4. Optional public goods game with uniform mutations.

Panel A shows abundance in stationarity as a function of the intensity of selection. Continuous lines represent the theoretical approximation. Dots represent simulation results averaged over 500 repetitions of generations each, and a mutation probability . Plus signs represent a larger mutation probability, . , , , , . Panel B shows transitions () between monomorphic states and abundance as a function of population size in the limit of strong selection ().