Ecology Of Species Interactions 5

Question 1

Which of the following describes a defensive mutualism?

Accepted Answer

Acacia trees producing hollow thorns inhabited by ants that attack herbivores

Answer

Acacia–ant mutualisms are classic defensive mutualisms: ants receive shelter and food while defending the tree from herbivores and competing plants.

Question 2

An ecologist finds that when a competitively dominant species is removed from a community, species diversity increases. This removal experiment demonstrates:

Accepted Answer

Competitive exclusion in action

Answer

When removing the dominant competitor raises diversity, it shows that dominant species were competitively excluding others—competitive exclusion in action.

Question 3

Character displacement refers to the evolutionary pattern where:

Accepted Answer

Competing species evolve greater differences in traits to reduce niche overlap

Answer

Character displacement describes divergent evolution of traits (e.g., beak size) in sympatric competing species, reducing niche overlap.

Question 4

In host–parasite coevolution, the 'Red Queen hypothesis' predicts that:

Accepted Answer

Hosts and parasites must continuously evolve to maintain fitness relative to each other

Answer

The Red Queen hypothesis states that hosts and parasites must keep evolving just to maintain the same relative fitness in an ongoing evolutionary arms race.

Question 5

Zoochory is a dispersal mechanism in which seeds are dispersed by:

Accepted Answer

Animals

Answer

Zoochory refers to seed dispersal by animals, including external attachment (epizoochory) or ingestion and defecation (endozoochory).

Ecology Practice Test

Ecology Practice Test

Ecology Of Species Interactions 5