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arXiv · 1012.5343

Speeding up evolutionary search by small fitness fluctuations

Jakub Otwinowski·Sorin Tanase-Nicola·Ilya Nemenman
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Abstract

We consider a fixed size population that undergoes an evolutionary adaptation in the weak mutuation rate limit, which we model as a biased Langevin process in the genotype space. We show analytically and numerically that, if the fitness landscape has a small highly epistatic (rough) and time-varying component, then the population genotype exhibits a high effective diffusion in the genotype space and is able to escape local fitness minima with a large probability. We argue that our principal finding that even very small time-dependent fluctuations of fitness can substantially speed up evolution is valid for a wide class of models.

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Jakub Otwinowski, Sorin Tanase-Nicola, Ilya Nemenman. 2010-12-24. Speeding up evolutionary search by small fitness fluctuations. https://doi.org/10.1007/s10955-011-0199-6

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