Figure 5

Direct observation of interdependent network reciprocity.

From left to right, panels (a)–(d) depict the evolution of cooperation in one network, while panels (e)–(h) show the same for the other network. Starting from a prepared initial state, only those circular cooperative domains that are initially present on both networks and which can therefore make immediate use of interdependent network reciprocity, survive and eventually spread across both networks. Cooperators that are initially distributed uniformly at random, as well as clustered cooperators present on one but not the other network, surrender under the evolutionary pressure from defectors already at the early stages of evolution. The applied system size was 2 × 200 × 200 at r/G = 0.66, α = 0.15 and β = 0.5. Snapshots were taken at t = 0, 100, 500 and 10000 MC steps.