Ecological niche

In ecology, a niche refers to the specific environmental condition occupied by a species or population. Different definitions have been proposed for the ecological niche, though they mainly revolve around describing the relationship between a species or population and its environment.

The term was coined in 1910 by Roswell Hill Johnson, but the first conceptual work done in the context of ecology research was by Joseph Grinnell in 1917. A Grinnellian niche is determined by the habitat in which a species lives and its accompanying behavioral adaptations. In 1927, Charles Sutherland Elton provided another definition for the ecological niche.The Eltonian niche differs from Grinnell's definition by emphasizing the role that a species plays in its biotic environment, its relationship to the ecosystem, and its use of resources. In 1957, G. Evelyn Hutchinson coined the Hutchinsonian niche as the set of environmental variables and their ranges over which a species can persist. Contemporary conceptions of the ecological niche attempt to reconcile these different definitions, however, differences in interpretation continue.

Ecological niches are an important concept in ecology research aiming to understand species diversity and coexistence. In contemporary niche theory, species with overlapping niches should be in competition with the superior competitor eliminating the inferior competitor. Species coexistence under this framework requires differences in two species' ecological niches.

The concept of the ecological niche is central to ecological biogeography, which focuses on spatial patterns of ecological communities.