Exam 16: Community Structure

The greater the number of links in a food chain,the higher the

When an ecologist compares the diversity of different communities by counting the number of species within each community,the measure of diversity being used is called

If a forest canopy is dense and closed,the understory and shrub layers tend to be well developed.

The percentage of individuals in a community that belong to one species is called the relative ________ of that species.

The layer of a forest in which decomposition takes place and mineral nutrients are released for reuse by plants is called the

A species that has a disproportionate impact on a community,relative to its abundance,is called a(n)________ species.

The view developed by H.A.Gleason that communities result from similarities in species' requirements and tolerances for environmental factors is referred to as the ________ concept of communities.

The characteristics of a community are generally not dependent on the spatial scale at which the community is examined because communities are tightly integrated groups of species.

________ index (D)represents the probability that two individuals randomly selected from a sample will belong to the same species.

An ecologist samples the abundance of various species along an environmental gradient and fails to find clusters of species.Instead,peaks of abundance of dominant species are merely randomly spaced segments along a continuum.This distribution of species supports the