Before revision:  Remarkably, our criterion for the onset of contagion turns out to be isomorphic to a simple rule for the evolution of cooperation on graphs and social networks, supporting recent calls for a methodological rapprochement between finance and ecology.
After revision:  Remarkably, our criterion for the onset of contagion turns out to be isomorphic to a simple rule for the evolution of cooperation on graphs and social networks, as recently formulated in evolutionary game theory. This remarkable connection supports recent calls for a methodological rapprochement between finance and ecology.