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arXiv · 1903.02226

Density-dependent feedback in age-structured populations

Jonathan Andersson·Vladimir Kozlov·Vladimir G. Tkachev·Sonja Radosavljevic·Uno Wennergren
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Abstract

The population size has far-reaching effects on the fitness of the population, that, in its turn influences the population extinction or persistence. Understanding the density- and age-dependent factors will facilitate more accurate predictions about the population dynamics and its asymptotic behaviour. In this paper, we develop a rigourous mathematical analysis to study positive and negative effects of increased population density in the classical nonlinear age-structured population model introduced by Gurtin \& MacCamy in the late 1970s. One of our main results expresses the global stability of the system in terms of the newborn function only. We also derive the existence of a threshold population size implying the population extinction, which is well-known in population dynamics as an Allee effect.

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Jonathan Andersson, Vladimir Kozlov, Vladimir G. Tkachev, Sonja Radosavljevic, Uno Wennergren. 2019-03-06. Density-dependent feedback in age-structured populations. https://doi.org/10.1007/s10958-019-04464-x

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