Chapter 17: Community Structure

Question 1

The group of species that occupy a given area, interacting either directly or indirectly.

Answer 1

Community

Question 2

The number of species occurring within the community.

Answer 2

Species richness

Question 3

The percentage each species contributes to the total number of individuals of all species.

Answer 3

Relative abundance

Question 4

A curve that compares patterns of species richness and abundance between communities where relative abundance for each species is plotted against rank.

Answer 4

Rank-abundance diagram

Question 5

A measure of how evenly individuals among species are distributed.

Answer 5

Species evenness

Question 6

These consider both the number and relative abundance of species within the community.

Answer 6

Diversity indexes

Question 7

This index measure the probability that two individuals randomly selected from a sample will belong to the same species.

Answer 7

Simpson’s index (D)

Question 8

The value of D for Simpson’s index ranges between ___ and ___.

Answer 8

Zero and one.

Question 9

When there is only one species present, the value of H for the Shannon diversity index is ___.

Answer 9

Zero

Question 10

When a single or few species predominate within a community, those species are called ___.

Answer 10

Dominants

Question 11

The converse of diversity is ___.

Answer 11

Dominance

Question 12

In the Shannon diversity index, a value of 1 for D represents ___.

Answer 12

Complete dominance

Question 13

A species that has a disproportionate impact on the community relative to its abundance.

Answer 13

Keystone species

Question 14

A descriptive diagram representing the flow of food energy from prey to predator.

Answer 14

Food chain

Question 15

These species feed on no other species but are fed on by others.

Answer 15

Basal species

Question 16

These species feed on other species and are also prey of other species.

Answer 16

Intermediate species

Question 17

These species are not subject to predators and prey on intermediate and basal species.

Answer 17

Top predators

Question 18

Feeding groups based on consumption of plant tissues, animal tissues, or both are called ___.

Answer 18

Trophic levels

Question 19

Trophic levels divided into groups of species that exploit the same resources are called ___.

Answer 19

Guilds

Question 20

Groups of species based on their common response to the environment, life history characteristics, or role within the community are called ___.

Answer 20

Functional types

Question 21

Classification of plants based on their photosynthetic pathway (C3, C4, and CAM) is an example of ___.

Answer 21

Functional types

Question 22

This index measures the similarity between two areas or sample plots based on species composition.

Answer 22

Sorensen’s coefficient of community.

Question 23

The organismic concept of communities was developed by ___.

Answer 23

Clements

Question 24

This view of communities states that they are like organisms, with each species representing an interacting, integrated component of the whole.

Answer 24

Organismic concept of communities

Question 25

The individualistic concept of communities was developed by ___.

Answer 25

Gleason

Question 26

This view of communities states that the relationship between coexisting species within a community is due to similarities within their requirements and tolerances, not due to strong interactions or common evolutionary history.

Answer 26

Individualistic/continuum concept