Fig. 2. Geographical distribution of studies examining the effect of dispersal on range size. We evaluated this for different clades: animals (fish and bird silhouettes), plants (leaf silhouette), diatoms (diatom silhouette) and mycorrhiza (root silhouette), and realms: terrestrial (brown), freshwater (green) and marine (blue). Except for global studies, studies that were carried out in more than one region are included in each region separately. Geographic location is separated according to the geographical region the study was carried out in, following the Wallace classification for terrestrial and freshwater organisms and marine ecoregions of the world-MEOW for marine organisms.