Dispersal Rates Under Variable Patch Density

This paper presents an inclusive-fitness model for the evolution of dispersal rates in subdivided populations where patches vary in the density of resources available for breeding and relatedness among patch mates of the same sex. If male and female relatednesses and male immigration rate are independent of patch density, then the model predicts that the mean number of non-dispersers per unit of reproductive resource remains constant among patches. Experimental data from the colonial, wing-polymorphic thrips of the species Hoplothrips karnyi support this prediction of the "constant-non-disperser" principle.