Dynamics of many species through competition for resources

TL;DR

This paper develops a mathematical model for species competition over resources, analyzing the emergence of stable species distributions, and provides algorithms and numerical examples to understand their dynamics and survival conditions.

Contribution

It introduces a new differential equation model derived from MacArthur's competition model, proves the existence of stable distributions, and offers computational methods for these distributions.

Findings

Existence of evolutionary stable distribution (ESD) proven.

Solutions tend to discrete ESD over time.

Numerical examples illustrate biological phenomena.

Abstract

This paper is concerned with a mathematical model of competition for resource where species consume noninteracting resources. This system of differential equations is formally obtained by renormalizing the MacArthur's competition model at equilibrium, and agrees with the trait-continuous model studied by Mirrahimi S, Perthame B, Wakano JY [J. Math. Biol. 64(7): 1189-1223, 2012]. As a dynamical system, self-organized generation of distinct species occurs. The necessary conditions for survival are given. We prove the existence of the evolutionary stable distribution (ESD) through an optimization problem and present an independent algorithm to compute the ESD directly. Under certain structural conditions, solutions of the system are shown to approach the discrete ESD as time evolves. The time discretization of the system is proven to satisfy two desired properties: positivity and energy dissipation. Numerical examples are given to illustrate certain interesting biological phenomena.