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arXiv · 1710.01496

Reducing the extinction risk of stochastic populations via non-demographic noise

Shay Be'er·Michael Assaf
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Abstract

We consider non-demographic noise in the form of uncertainty in the reaction step size, and reveal a dramatic effect this noise may have on the stability of self-regulating populations. Employing the reaction scheme mA->kA, but allowing, e.g., the product number k to be a-priori unknown and sampled from a given distribution, we show that such non-demographic noise can greatly reduce the population's extinction risk compared to the fixed k case. Our analysis is tested against numerical simulations, and by using empirical data of different species, we argue that certain distributions may be more evolutionary beneficial than others.

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Shay Be'er, Michael Assaf. 2018-02-11. Reducing the extinction risk of stochastic populations via non-demographic noise. https://doi.org/10.1103/physreve.97.020302

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