Stochastic eco-evolutionary model of a prey-predator community

J Math Biol. 2016 Feb;72(3):573-622. doi: 10.1007/s00285-015-0895-y. Epub 2015 May 23.

Abstract

We are interested in the impact of natural selection in a prey-predator community. We introduce an individual-based model of the community that takes into account both prey and predator phenotypes. Our aim is to understand the phenotypic coevolution of prey and predators. The community evolves as a multi-type birth and death process with mutations. We first consider the infinite particle approximation of the process without mutation. In this limit, the process can be approximated by a system of differential equations. We prove the existence of a unique globally asymptotically stable equilibrium under specific conditions on the interaction among prey individuals. When mutations are rare, the community evolves on the mutational scale according to a Markovian jump process. This process describes the successive equilibria of the prey-predator community and extends the polymorphic evolutionary sequence to a coevolutionary framework. We then assume that mutations have a small impact on phenotypes and consider the evolution of monomorphic prey and predator populations. The limit of small mutation steps leads to a system of two differential equations which is a version of the canonical equation of adaptive dynamics for the prey-predator coevolution. We illustrate these different limits with an example of prey-predator community that takes into account different prey defense mechanisms. We observe through simulations how these various prey strategies impact the community.

Keywords: Adaptive dynamics; Long time behavior of dynamical systems; Lotka-Volterra equations; Multi-type birth and death process; Mutation selection process; Polymorphic evolution sequence; Predator-prey.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological
  • Animals
  • Biological Evolution*
  • Computational Biology
  • Ecosystem
  • Markov Chains
  • Mathematical Concepts
  • Models, Biological*
  • Mutation
  • Phenotype
  • Population Dynamics
  • Predatory Behavior*
  • Selection, Genetic
  • Stochastic Processes