Evolution of dispersal polymorphism and local adaptation of dispersal distance in spatially structured landscapes

Authored by Hans Joachim Poethke, Thomas Hovestadt, Dries Bonte

Date Published: 2010

DOI: 10.1111/j.1600-0706.2009.17943.x

Sponsors: German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) Fund for Scientific Research Flanders

Platforms: QRULE

Model Documentation: Other Narrative Mathematical description

Model Code URLs: Model code not found

Abstract

Many organisms show polymorphism in dispersal distance strategies. This variation is particularly ecological relevant if it encompasses a functional separation of short- (SDD) and long-distance dispersal (LDD). It remains, however, an open question whether both parts of the dispersal kernel are similarly affected by landscape related selection pressures. We implemented an individual-based model to analyze the evolution of dispersal traits in firactal landscapes that vary in the proportion of habitat and its spatial configuration. Individuals are parthenogenetic with dispersal distance determined by two alleles oil each individual's genome: one allele coding for the probability of global dispersal and one allele coding for the variance sigma of a Gaussian local dispersal with mean value zero. Simulations show that mean distances of local dispersal and the probability of global dispersal, increase with increasing habitat availability, but that changes in the habitats spatial autocorrelation impose opposing selective pressure: local dispersal distances decrease and global dispersal probabilities increase with decreasing spatial autocorrelation of the available habitat. Local adaptation of local dispersal distance emerges in landscapes with less than 70\% of clumped habitat. These results demonstrate that long and short distance dispersal evolve separately according to different properties of the landscape. The landscape structure may consequently largely affect the evolution of dispersal distance strategies and the level of dispersal polymorphism.

Tags

Migration models Dynamics Habitat fragmentation Populations Kin selection Gene flow Reduced dispersal Wolf spider Crepis-sancta