Mutation promote cooperation in repeated games on structured populations

Area of Science:

• Evolutionary Game Theory
• Behavioral Economics
• Network Science

Background:

• Cooperation is vital in societies but hard to maintain among rational agents.
• Realistic interactions occur on networks, not in well-mixed populations.
• Mutation introduces variation, potentially impacting cooperation dynamics.

Purpose of the Study:

• To investigate the role of mutation in promoting cooperation on structured populations.
• To understand how mutation rates affect cooperation in network reciprocity scenarios.
• To identify conditions under which mutation facilitates cooperation.

Main Methods:

• Agent-based simulations of repeated games on structured populations.
• Systematic variation of mutation rates and payoff parameters.
• Analysis of cooperation levels across different network structures (Erdős-Rényi networks).

Main Results:

• Cooperation is difficult to sustain with very rare mutation.
• Moderate mutation rates significantly enhance cooperation.
• Optimal mutation regimes exist, dependent on payoff values and strategy sets.
• Mutation facilitates cooperation even with low benefit-cost ratios (slightly > 1).
• The promoting effect of mutation is robust across various network structures.

Conclusions:

• Mutation is a crucial factor in sustaining cooperation on networks.
• A moderate mutation rate is essential for promoting cooperation, contrary to intuition.
• These findings have implications for understanding cooperation in biological and social systems.