succession

succession The sequential change in vegetation and the animals associated with it, either in response to an environmental change or induced by the intrinsic properties of the organisms themselves. Classically, the term refers to the colonization of a new physical environment by a series of vegetation communities until a final equilibrium state, the climax, is achieved. The presence of the colonizers, the pioneer plant species, modifies the environment so that new species can join or replace the initial colonizers. Changes are rapid at first but slow to a more or less imperceptible rate at the climax stage, composed of climax plant species. The term applies to animals (especially to sessile animals in aquatic ecosystems) as well as to plants. The characteristic sequence of developmental stages (i.e. nudation, migration, ecesis, competition, reaction, and stabilization) is termed a sere. See allogenic; autogenic; and degradative.