File:Greed-and-Fear-in-Network-Reciprocity-Implications-for-Cooperation-among-Organizations-pone.0147264.s005.ogv

English: Fear intervention, crossing from the diffusion region (Greed = 3.4; Fear = 1.9) to the consolidation region (Greed = 3.4; Fear = 2.0), with 90% initial cooperators. The first part of this video illustrates a typical evolution of cooperation within the diffusion region, with parameters identical to the second half of S4 Video. Cooperation rapidly spreads over the lattice. After the model reaches equilibrium with scattered defectors (red) surrounded by cooperators (blue), an exogenous intervention increases Fear from 1.9 to 2.0, returning to the consolidation region at the start of S4 Video. Although payoffs thus cross the same boundary in reverse, the system-level cooperation does not fall to the bottom of the cliff, but maintains the high level of cooperation. This illustrates the asymmetry in Fear interventions, which makes many Fear-sensitive boundaries one-way upward.