The Evolution of Male-Biased Dispersal under the Joint Selective Forces of Inbreeding Load and Demographic and Environmental Stochasticity

Authored by Justin MJ Travis, Roslyn C Henry, Aurelie Coulon

Date Published: 2016

DOI: 10.1086/688170

Sponsors: United Kingdom Natural Environment Research Council (NERC)

Platforms: C++

Model Documentation: Other Narrative Flow charts Mathematical description

Model Code URLs: http://datadryad.org/resource/doi:10.5061/dryad.11vb2

Abstract

Sex-biased natal dispersal is widespread, and its significance remains a central question in evolutionary biology. However, theory so far fails to predict some of the most common patterns found in nature. To address this, we present novel results from an individual-based model investigating the joint roles of inbreeding load, demographic stochasticity, environmental stochasticity, and dispersal costs for the evolution of sex-biased dispersal. Most strikingly, we found that male-biased natal dispersal evolved in polygynous systems as a result of the interplay between inbreeding avoidance and stochasticity, whereas previous theory, in contrast to empirical observations, predicted male philopatry and female-biased natal dispersal under inbreeding load alone. Furthermore, the direction of the bias varied according to the nature of stochasticity. Our results therefore provide a unification of previous theory, yielding a much better qualitative match with empirical observations of male-biased dispersal in mate defense mating systems.

Tags

Mate Choice Rates Density-dependence Red deer Habitat fragmentation Population genetic-structure Egernia-cunninghami Local extinction Heterozygosity Philopatry