Question

Gause’s principle of competitive exclusion states that -
(a)Larger organisms exclude smaller ones through competition
(b)More abundant species will exclude the less abundant species through competition
(c)Competition for the same resources excluding species having different food preferences
(d)No two species can occupy the same niche indefinitely for the same limiting resource.

Answer 1

Hint Gause’s principle or the competitive exclusion principle explains how competing related species often evolve distinguishing characteristics in areas where they both coexist. In an ecosystem, when two competing life forms attempt to occupy the same niche, one life form will inevitably drive out the other.

Complete answer: - The Gause’s principle of competitive exclusion states that two species that compete for the exact same resources cannot stably coexist.
- One of the two competing species will always have an advantage, even to the lowest degree, over the other that leads to the extinction of the second competitor in the long run in a hypothetical scenario or to an evolutionary shift of the inferior competitor towards a different ecological niche in a real setting.
- As a result, the competing related species often evolve distinguishing characteristics in areas where they both coexist.

Additional information: - Competitive exclusion is not observed accurately in natural ecosystems. For example, all plankton species live on a very limited number of resources like solar energy and minerals dissolved in the water. According to competitive exclusion, only a few species of plankton should be able to coexist on these resources. Nevertheless, large numbers of plankton coexist within small regions of the open sea.
- This is known as the paradox of the plankton.

So, the correct answer is ‘No two species can occupy the same niche indefinitely for the same limiting resource.’

Note: - Although the principle is credited to Gause, it is available in Darwin’s theory of natural selection.
- Competitive exclusion is also observed in human beings in war and peace like conditions.