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Black smokers create ecological niches with their unusual environment In ecology, a niche (CanE, UK /ˈniːʃ/ or US /ˈnɪtʃ/) is a term describing the way of life of a species. Each species is thought to have a separate, unique niche. The ecological niche describes how an organism or population responds to the distribution of resources and competitors (e.g., by growing when resources are abundant, and when predators, parasites and pathogens are scarce) and how it in turn alters those same factors (e.g., limiting access to resources by other organisms, acting as a food source for predators and a consumer of prey). The majority of species exist in a standard ecological niche. A premier example of a non-standard niche filling species is the flightless, ground-dwelling kiwi bird of New Zealand, which exists on worms, and other ground creatures, and lives its life in a mammal niche. Island biogeography can help explain island species and associated unfilled niches. Contents[hide] * 1 Grinnellian niche * 2 Eltonian niche * 3 Hutchinsonian niche * 4 Parameters * 5 See also * 6 References * 7 External links|  Grinnellian niche
The word "niche" is derived from the Middle French word nicher, meaning to nest. The term was coined by the naturalist Joseph Grinnell in 1917, in his paper "The niche relationships of the California Thrasher." The Grinnellian niche concept embodies the idea that the niche of a species is determined by the habitat in which it lives. In other words, the niche is the sum of the habitat requirements that allow a species to persist and produce offspring. For example, the behavior of the California Thrasher is consistent with the chaparral habitat it lives in—it breeds and feeds in the underbrush and escapes from its predators by shuffling from underbrush to underbrush. This perspective of niche allows for the existence of ecological equivalents and also empty niches. For example, the Anolis lizards of the Greater Antilles are a rare example of convergent evolution, adaptive radiation, and the existence of ecological equivalents: the Anolis lizards evolved in similar microhabitats independently of each other and resulted in the same ecomorphs across all four islands.  Eltonian niche
In 1927 Charles Sutherland Elton, a British ecologist, gave the first working definition of the niche concept. He is credited with saying: "[W]hen an ecologist says 'there goes a badger,' he should include in his thoughts some definite idea of the animal's place in the community to which it belongs, just as if he had said, 'there goes the vicar.'" The Eltonian niche encompasses the idea that the niche is the role a species plays in a community, rather than a habitat.  Hutchinsonian niche
Squirrels in public parks may have a different ecological niche than those with less human contact. The Hutchinsonian niche views niche as an n-dimensional hypervolume, where the dimensions are environmental conditions and the resources that define the requirements of an individual or a species to practise "its" way of life. The niche concept was popularized by the zoologist G. Evelyn Hutchinson in 1957. Hutchinson wanted to know why there are so many different types of organisms in any one habitat. An organism free of interference from other species could use the full range of conditions (biotic and abiotic) and resources in which it could survive and reproduce which is called its fundamental niche. However, as a result of pressure from, and interactions with, other organisms (i.e. inter-specific competition) species are usually forced to occupy a niche that is narrower than this, and to which they are mostly highly adapted. This is termed the realized niche. The ecological niche has also been termed by G. Evelyn Hutchinson a "hypervolume." This term defines the multi-dimensional space of resources (e.g., light,...