Figure 2.
Invasion and stability conditions for cooperation and cognition. (a) Parameter space where full cooperation is stable (and can invade), with and without cognition, as a function of relatedness and the per capita benefit to cost ratio from cooperation (scaled by group size n). Increasing the synergy factor α increases the stability of full cooperation, even without relatedness (Ro = 0). (b) Level of cooperation required for cognition to invade, in function of relatedness and the per capita share to cost ratio from cognition (scaled by group size n). Parameters in (a) bC = 2.5; in both panels n = 15, c = 0.1, and d = 0.05.