Figure 6.
We use prepared initial conditions as shown, so that the population cannot evolve into a homogeneous absorbing state during the first period of τ even under the most adverse conditions. For this to hold, the linear size of each square should be more than four times larger than τ. Blue color depicts cooperators (si = C), while the red color depicts defectors (si = D). Both strategies have equal occupance of the population at the start of evolution.