Niche, competitive exclusion, keystone species (1)

Ecological Niche

The role (job) and position (space) a species has within an ecosystem, including its interactions with biotic and abiotic factors.

Competitive Exclusion Principle

The principle that states it is impossible for two species to occupy the same niche in the same habitat for an extended period of time.

Fundamental Niche

The area that should be occupied by a species based on the conditions described by a species’ niche without interference from other species.

Realized Niche

The area that is actually occupied by a species, typically smaller than the fundamental niche due to competition and other factors.

Resource Partitioning

The division of resources that enables ecologically similar species to coexist in a community by utilizing different aspects of their niches.

Gause's Experiment

An experiment by G.F. Gause that demonstrated competitive exclusion using two species of Paramecium, where one outcompeted the other.

Keystone Species

A species that has a disproportionately large effect on its environment relative to its abundance by maintaining local biodiversity.

Carrying Capacity

The greatest density of organisms that an environment can support.

Temporal Separation

A form of niche differentiation where species are more prevalent at different times of day or during different seasons.

Spatial Separation

A form of niche differentiation where different species inhabit separate habitat patches within the same environment.