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What are the differences between the interdependent community and independent community perspectives of Frederic Clements and Henry Gleason?

The species in interdependent communities all rely on each other for survival; species in independent communities do not rely on each other for survival


Given that the distributions of many animals are determined by the species composition of the plant community, what might you predict about the diversity of animals in an ecotone with a more diverse ecosystem on one side and a less diverse ecosystem on the other side?

The amount of diversity would be higher than either ecosystem


What did Robert Whittaker’s data on plant species composition along gradients of temperature and moisture in mountains show?

It provided evidence that challenged the concept of interdependent communities.


Species richness is

the number of species in a community.


The difference between log-normal abundance distributions and rank-abundance curves is

a rank-abundance curve orders species by abundance; a log-normal distribution groups similarly abundant species together.


Why does an increase in total resources or number of added resources commonly lead to declines in species diversity?

Species diversity is usually highest at intermediate values of resources.


At what frequency of disturbance would the most diversity be expected?

medium frequency


When discussing trophic levels a guild is

a group of species that feed on similar items.


Trait-mediated indirect effects

include effects caused by changes in the distribution or behavior of an intermediate species.


What does it mean when a community is said to exhibit top-down control?

The abundance of trophic groups is determined by the presence of predators.