Biology - 2.5 - Part 1 - Niche

What is an ecological niche?

A multi-dimensional summary of the tolerances and requirements of a species.

What is a fundamental niche?

A niche that a species occupies in the absence of interspecific competition.

What is a realised niche?

A niche that a species occupies in response to interspecific competition.

What can happen as a result of interspecific competition?

Competitive exclusion.

What is competitive exclusion?

When the niches of two different species are so similar that one of the species declines to local extinction.

What happens if the realised niches of two competing species are sufficiently different?

Resource partitioning.

What is resource partitioning?

Compromise over resources when the realised niches of two species in interspecific competition are sufficiently different that they can coexist.

What is parasitism?

A symbiotic relationship between a parasite and a host, where the parasite benefits and the host is harmed.

What does the parasite gain at the expense of the host?

Nutrients.

How is parasitism different from a predator-prey relationship?

parasites have a greater reproductive potential than the host.

Why do most parasites have a narrow (specialised) niche?

They are very host-specific.

What does it mean to say a parasite is degenerate?

It depends on its host for survival and it lacks the structures and organs found in other organisms.

Where does an ectoparasite live?

On the surface of the host.

Where does an endoparasite live?

Within the tissues of its host.