Competition between fast- and slow-diffusing species in non-homogeneous environments

Authored by Simone Pigolotti, Roberto Benzi

Date Published: 2016

DOI: 10.1016/j.jtbi.2016.01.033

Sponsors: spanish ministeries

Platforms: No platforms listed

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

We study an individual-based model in which two spatially distributed species, characterized by different diffusivities, compete for resources. We consider three different ecological settings. In the first, diffusing faster has a cost in terms of reproduction rate. In the second case, resources are not uniformly distributed in space. In the third case, the two species are transported by a fluid flow. In all these cases, at varying the parameters, we observe a transition from a regime in which diffusing faster confers an effective selective advantage to one in which it constitutes a disadvantage. We analytically estimate the magnitude of this advantage (or disadvantage) and test it by measuring fixation probabilities in simulations of the individual-based model. Our results provide a framework to quantify evolutionary pressure for increased or decreased dispersal in a given environment. (C) 2016 Elsevier Ltd. All rights reserved.
Tags
Evolution probability Dispersal population Model Demographic stochasticity Fixation Spatial variation