Solved: Distinguish between a fundamental niche and realized niche. Explain the impact of... [IB Biology]

Distinguish between a fundamental niche and realized niche.

[2]

Verified

Solution

Fundamental niche refers to the full range of environmental conditions and resources that a species can potentially exploit in the absence of competition or other limiting factors. It is the theoretical niche that a species is capable of occupying. 1 mark

\text{Fundamental niche} = \text{potential niche}

Realized niche refers to the actual set of environmental conditions and resources that a species occupies and uses, taking into account the presence of competitors, predators, and other biotic and abiotic factors that limit its distribution and abundance. It is the niche that a species actually occupies. 1 mark

\text{Realized niche} = \text{actual niche}

Explain the impact of competition on the niche of an organism.

[2]

Verified

Solution

a. competition can limit the niche ✓

b. competition can limit resources ✓

c. when competition is removed the niche can expand ✓

d. can result in exclusion or removal of a species from a niche / only one species can occupy a niche ✓

State the traits of keystone species in an ecosystem.

[1]

Verified

Solution

Keystone species has a strong/disproportionate effect on a community/food web/ecosystem ✓