biogeography

Study of how and why plants and animals are distributed around the world, in the past as well as in the present; more specifically, a theory describing the geographical distribution of species developed by Robert MacArthur and US zoologist Edward O Wilson. The theory argues that, for many species, ecological specializations mean that suitable habitats are patchy in their occurrence. For example, for a dragonfly, ponds in which to breed are separated by large tracts of land, and for edelweiss adapted to alpine peaks the deep valleys between cannot be colonized.