Amensalism Examples Quiz: Allelopathy and More

Questions and Answers

What are the two main reasons proposed for why competing species can coexist even when they have similar resource use?

Predator-mediated coexistence and open systems with migration (correct)

Niche differentiation and habitat heterogeneity

Resource partitioning and competitive exclusion

Keystone species interactions and environmental filtering

What is the mechanism behind predator-mediated coexistence?

Predators induce character displacement in competing species

Predators preferentially consume competitively dominant prey species (correct)

Predators reduce overall competition and promote niche partitioning

Predators create spatial heterogeneity that allows coexistence

How does migration and open systems allow competing species to coexist?

Migration allows competitively inferior species to recolonize areas where they have been excluded (correct)

Migration allows keystone species to maintain the community structure

Migration leads to genetic mixing that reduces competitive differences

Migration creates spatial heterogeneity that promotes niche partitioning

What is the key difference between predator-mediated coexistence and open systems with migration?

Predator-mediated coexistence involves selection by predators, while open systems involve dispersal Signup and view all the answers

Which of the following is not a characteristic of the predator-mediated coexistence mechanism?

Competitively inferior species are able to maintain populations indefinitely Signup and view all the answers

What is the key difference between predator-mediated coexistence and resource partitioning as mechanisms for species coexistence?

Predator-mediated coexistence allows competitively inferior species to persist, while resource partitioning does not Signup and view all the answers

Which of the following statements about predator-mediated coexistence is false?

It can only occur in closed systems without any migration or dispersal Signup and view all the answers

How does the mechanism of open systems with migration differ from predator-mediated coexistence in terms of species interactions?

Open systems involve both competition and dispersal, while predator-mediated coexistence involves only predation Signup and view all the answers

Which of the following is a key assumption of the predator-mediated coexistence mechanism?

Predators preferentially consume the more abundant prey species Signup and view all the answers

How does the open systems with migration mechanism differ from the predator-mediated coexistence mechanism in terms of the long-term stability of species coexistence?

Open systems allow for more stable, long-term coexistence, while predator-mediated coexistence is more short-term Signup and view all the answers

Study Notes

Species Coexistence and Resource Partitioning

Competing species may coexist due to resource partitioning, even if they have similar resource use.
Two reasons for coexistence: predator-mediated coexistence and migration from areas where species are competitively superior.

Predator-Mediated Coexistence

In the presence of high levels of predation, competitively dominant species may be selected by predators over less abundant prey.
Dominant competitors will never be able to eliminate poor competitors.

Migration and Coexistence

Many real populations in nature exist in open areas where migration is possible.
Immigration into areas where species are competitively inferior from areas where they are competitively superior will maintain populations of both competitors.

Allelopathy and Amensalism

Allelopathy is a phenomenon where chemicals (allelochemicals) inhibit the growth of other species.
Amensalism is a type of competition where one species is inhibited, and the other is not affected.

Types of Competition

Apparent competition: occurs indirectly between two species that are both preyed upon by the same predator.
Associational susceptibility: a type of apparent competition where herbivores spill over from one species to another.

Guilds and Resource Competition

Guilds are groups of species that feed on the same resource and in the same way.
Examples of guilds include leaf gleaning, ground-feeding, and stem-boring guilds.

Field Studies and Competition

Field studies have shown that competition is more frequent in guilds.
The stem-boring guild associated with salt-marsh cord grass is an example of resource competition.

Biological Control and Competition

Biological control agents may compete with each other, reducing their rates of establishment.
Introduced biological control agents may outcompete native species.
Releasing a single species may be a better strategy for biological control than releasing multiple species.

Allelopathy and Amensalism Examples Quiz