Speeding up Evolutionary Search by Small Fitness Fluctuations

• Type of Material: Article
• Authors: Jakub Otwinowski, Emory University; Sorin Tanase-Nicole, Emory University; Ilya Nemenman, Emory University
• Language: English
• Date: 2011-04-22
• Publisher: Springer Verlag (Germany)
• Publication Version: Final Published Version
• Copyright Statement: © The Author(s) 2011
• License: Creative Commons Attribution-NonCommercial 4.0 International
• Final Published Version (URL): http://link.springer.com/article/10.1007%2Fs10955-011-0199-6
• Title of Journal or Parent Work: Journal of Statistical Physics
• ISSN: 0022-4715
• Volume: 144
• Issue: 2
• Start Page: 367
• End Page: 378
• Keywords: Barrier crossing; Fixation; Stochastic process; Nonequilibrium
• Research Categories: Physics, General

Abstract

Abstract We consider a fixed size population that undergoes an evolutionary adaptation in the weak mutation 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 ofmodels.