Non-Ergodicity and The Evolution of Cooperation

Via Lars P. Syll:

Cooperation, here, is a persistent behavioural pattern of individual entities pooling and sharing resources …

Here we point out a very general mechanism – a sufficient null model – whereby cooperation can evolve. The mechanism is based the following insight: natural growth processes tend to be multiplicative. In multiplicative growth, ergodicity is broken in such a way that fluctuations have a net-negative effect on the time-average growth rate, although they have no effect on the growth rate of the ensemble average. Pooling and sharing resources reduces fluctuations, which leaves ensemble averages unchanged but – contrary to common perception – increases the time-average growth rate for each cooperator …

Economics should be the place to look for an explanation of human social structure, but oddly the basic message from mainstream economics seems to be that optimal, rational, sensible behaviour would shun cooperation. In many ways we see cooperation in the world despite, not because of, economic theory.

Many economists are aware of this shortcoming of their discipline and are address- ing it, often from psychological or neurological perspectives, as well as with the help of agent-based evolutionary simulations.

We show that cooperation and social structure arise from simple analytically solv- able mathematical models for economically optimal behaviour....MORE