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arXiv · 2610.05857

Stochastic evolutionary dynamics in structured populations: Network degree governs evolutionary stability

Vikash Kumar Dubey·Sagar Chakraborty
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Abstract

Stochasticity shapes evolutionary dynamics in finite populations beyond the reach of infinite-population theories. Using a stochastic birth--death framework on random regular networks, we establish evolutionary stability criteria for finite structured populations playing three-strategy games and identify critical degree thresholds governing invasion dynamics. Our framework goes beyond two-strategy evolutionary games to reveal that the initial composition of multi-type mutants, together with population structure and stochasticity, shapes the evolutionary fate of the resident population.

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Vikash Kumar Dubey, Sagar Chakraborty. 2026-10-05. Stochastic evolutionary dynamics in structured populations: Network degree governs evolutionary stability. https://arxiv.org/abs/2610.05857

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