Page "Ecology" Paragraph 27

Definitions of the niche date back to 1917, but G. Evelyn Hutchinson made conceptual advances in 1957 by introducing a widely adopted definition: " the set of biotic and abiotic conditions in which a species is able to persist and maintain stable population sizes.

" The ecological niche is a central concept in the ecology of organisms and is sub-divided into the fundamental and the realized niche.

The fundamental niche is the set of environmental conditions under which a species is able to persist.

The realized niche is the set of environmental plus ecological conditions under which a species persists.

The Hutchinsonian niche is defined more technically as a " Euclidean hyperspace whose dimensions are defined as environmental variables and whose size is a function of the number of values that the environmental values may assume for which an organism has positive fitness.