Ecological Variables Affecting the Dispersal Behavior of Drosophila pseudoobscura and Its Relatives

Abstract

Dispersal behavior of Drosophila spp. of the American D. obscura groups is strongly affected by ecological factors. In some habitats the flies move very rapidly while in others they are quite sedentary. In an attempt to quantify the spatial variation in dispersal, computer simultations were performed based on diffusion equations. Different dispersal coefficients were assigned to the 6 different habitat types identified in the area. The best-fit simulations indicate that dispersal rates vary by nearly 1 order of magnitude in an area a few hundred meters square. Such variation in dispersal behavior affects the population genetic structure and evolution of populations.