What is actually meant by the term fundamental niche?

In ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other; The ecological niche describes how an organism or population responds to the distribution of resources and competitors and how it in turn alters those same factors. It can be of different types: Fundamental niche, Realized niche, Ecological niche, Spatial Niche, Trophic niche.

It refers to an actual niche space occupied by organisms exposed to competition.

It is the ultimate distributional unit within which no two species in the same general territory can occupy for long the same ecological niche.

It represents niche in terms of functional status of organisms in community.

It is the physical space occupied by organisms.

Fundamental niche can be defined as a niche that the species can occupy when the species are not restricted by degree of competition and predation.