Dominance is an ecological term that refers to the degree that a particular species is prevalent within its community, in terms of its relative size, productivity, or cover. Because of their ability to appropriate space, nutrients, and other resources, dominant species have a relatively strong or controlling influence on the structure and functions of their community, and on the fitness and productivity of other species. Ecological communities are often characterized on the basis of their dominant species.

Species may become dominant within their community if they are particularly competitive, that is, if they are relatively successful under conditions in which the availability of resources constrains ecological productivity and community structure. As such, competitive species are relatively efficient at obtaining resources. For example, competitive terrestrial plants are relatively efficient at accessing nutrients, moisture, and space, and they are capable of regenerating beneath their own shade. These highly competitive species...