Geodispersal
In biogeography, geodispersal is the erosion of barriers to gene flow and biological dispersal (Lieberman, 2005.; Albert and Crampton, 2010.). Geodispersal differs from vicariance as a means of explaining the patterns of distribution among related species. In geodispersal, the geographical ranges of individual taxa, or of whole biotas, are merged by erosion of a physical barrier to gene flow or dispersal.