Strong Noise Effects in one-dimensional Neutral Populations

Luca Dall'Asta; Fabio Caccioli; Deborah Beghè

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arXiv · 1012.1209

Strong Noise Effects in one-dimensional Neutral Populations

Luca Dall'Asta·Fabio Caccioli·Deborah Beghè

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Abstract

The dynamics of well-mixed biological populations is usually studied by mean-field methods and weak-noise expansions. Similar methods have been applied also in spatially extended problems, relying on the fact that these populations are organized in colonies with a large local density of individuals. We provide a counterexample discussing a one-dimensional neutral population with negative frequency-dependent selection. The system exhibits a continuous phase transition between genetic fixation and coexistence unexpected from weak-noise arguments. We show that the behavior is a non-perturbative effect of the internal noise that is amplified by presence of spatial correlations (strong-noise regime).

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Luca Dall'Asta, Fabio Caccioli, Deborah Beghè. 2010-12-06. Strong Noise Effects in one-dimensional Neutral Populations. https://arxiv.org/abs/1012.1209

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