Fig. 1

Proportion infected by benefit of health and network type. For each level of benefit b shown, I ran one simulation run lasting 500 steps (game plays) and calculated the averaged the proportion infected. The simulation runs all start with a random distribution of 50 protectors and 50 % defectors, and 10 % of individuals infected. In the grid lattice network, when the health benefit is below 4, health protection and so infection spreads unabated