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arXiv · 1210.0018

Survival of the Scarcer

Alan Gabel·Baruch Meerson·S. Redner
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Abstract

We investigate extinction dynamics in the paradigmatic model of two competing species A and B that reproduce (A-->2A, B-->2B), self-regulate by annihilation (2A-->0, 2B-->0), and compete (A+B-->A, A+B-->B). For a finite system that is in the well-mixed limit, a quasi-stationary state arises which describes coexistence of the two species. Because of discrete noise, both species eventually become extinct in time that is exponentially long in the quasi-stationary population size. For a sizable range of asymmetries in the growth and competition rates, the paradoxical situation arises in which the numerically disadvantaged species according to the deterministic rate equations survives much longer.

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BibTeXRIS

Alan Gabel, Baruch Meerson, S. Redner. 2012-12-27. Survival of the Scarcer. https://doi.org/10.1103/physreve.87.010101

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