Species Niche and Competition Concepts

The video discusses how organisms compete for limited resources, using Paramecium species as an example. It explains the competitive exclusion principle, which states that two species cannot occupy the same niche if they are in direct competition. The video also explores how niches can change in a marine ecosystem, highlighting the difference between realized and fundamental niches.

What happens when two species of Paramecium are raised in isolation?

• They merge into a single species.

• Both populations decline immediately.

• One species always outcompetes the other.

• Both populations thrive until their food source runs out.

What does the competitive exclusion principle state?

• Two species in direct competition cannot occupy the same niche.

• Species in competition will always go extinct.

• Two species can always share the same niche.

• Species in competition will always merge.

What is the main focus of the experiment conducted by GF Gauss?

• To prove that species never compete.

• To demonstrate that species always merge.

• To illustrate the competitive exclusion principle.

• To show that two species can share the same niche.

How can two species coexist in the same environment?

• By using resources in slightly different ways.

• By occupying the same niche.

• By merging into a single species.

• By avoiding each other completely.

In the marine ecosystem example, what happens to the familis barnacle when there is no competition?

• It goes extinct.

• It occupies only the high tide region.

• It occupies both high and low tide regions.

• It is outcompeted by balanus barnacles.

What is the realized niche of a species?

• The role it plays in a different ecosystem.

• The role it plays in a hypothetical ecosystem.

• The role it plays in the ecosystem with competitors.

• The role it plays in the ecosystem without competitors.

What happens to the balanus barnacle in the presence of competition?

• It goes extinct.

• It occupies both high and low tide regions.

• It occupies only the high tide region.

• It outcompetes the familis barnacle in the low tide region.

What is the fundamental niche of a species?

• The role it plays in the ecosystem with competitors.

• The role it plays in the ecosystem without competitors.

• The role it plays in a hypothetical ecosystem.

• The role it plays in a different ecosystem.

Why is it difficult to determine a species' fundamental niche?

• Because it requires adding more competitors.

• Because it requires changing the ecosystem.

• Because it requires merging species.

• Because it requires removing all competitors.

What is the effect of competition on a species' niche?

• It has no effect on the niche.

• It narrows the niche.

• It expands the niche.

• It eliminates the niche.