Question 1

How does an ecologist determine the presence of an ecotone?

Accepted Answer

A)  Measure the abundance of plant species over space and abrupt changes in species composition. 
B)  Perform controlled crosses among all plant species within a community to determine the extent to which the species are reproductively isolated. 
C)  Measure microclimate and soil variables for abrupt changes. 
D)  Measure elevation, since many environmental and ecological variables change with elevation. 
A)  Measure the abundance of plant species over space and abrupt changes in species composition. 
B)  Perform controlled crosses among all plant species within a community to determine the extent to which the species are reproductively isolated. 
C)  Measure microclimate and soil variables for abrupt changes. 
D)  Measure elevation, since many environmental and ecological variables change with elevation.

Question 2

Which relationships in the figure indicate top-down control? Which relationships indicate bottom-up control?

Accepted Answer

To provide an accurate answer to your qu

Question 3

Keystone species

Accepted Answer

A)  have the most biomass in a community. 
B)  are usually top predators. 
C)  can affect community structure regardless of population size. 
D)  are invasive predator species that eat native herbivores. 
A)  have the most biomass in a community. 
B)  are usually top predators. 
C)  can affect community structure regardless of population size. 
D)  are invasive predator species that eat native herbivores.

Question 4

In hiking up a mountain you are likely to pass through various community types as you proceed from the low-elevation lands to the summit. As you proceed from one community type to another, a boundary between community types, created by changing environmental conditions, will be observed. This boundary area of overlap/blending is termed the _____ and has _____ level of biodiversity as compared to each of the two communities on either side of the boundary area.

Accepted Answer

A)  ecotone; a lower 
B)  ecotone; a higher 
C)  transition zone; the same 
D)  transition zone; lower 
A)  ecotone; a lower 
B)  ecotone; a higher 
C)  transition zone; the same 
D)  transition zone; lower

Question 5

What do the data in the graphs suggest about the resistance of the community to disturbance?

Accepted Answer

A)  Communities with any amount of plants are very resistant to disturbance. 
B)  Community resistance depends on whether herbivores, predators, and parasites are present. 
C)  Herbivore species richness and abundance both increase with small changes in plant species richness. 
D)  The stability of herbivore species richness and abundance responds independently of plant species richness. 
A)  Communities with any amount of plants are very resistant to disturbance. 
B)  Community resistance depends on whether herbivores, predators, and parasites are present. 
C)  Herbivore species richness and abundance both increase with small changes in plant species richness. 
D)  The stability of herbivore species richness and abundance responds independently of plant species richness.

Question 6

Whitaker's classic study of trees in the Great Smoky Mountains provided evidence of the fact that

Accepted Answer

A)  ecotones are only temporary. 
B)  in a community, as environmental conditions change, all tree species respond in the same manner relative to abundance. 
C)  changes in tree species abundance impacts herbivores. 
D)  when environmental changes occur in a community-specific tree species, abundance values change independently of other trees. 
A)  ecotones are only temporary. 
B)  in a community, as environmental conditions change, all tree species respond in the same manner relative to abundance. 
C)  changes in tree species abundance impacts herbivores. 
D)  when environmental changes occur in a community-specific tree species, abundance values change independently of other trees.

How does an ecologist determine the presence of an ecotone?

Which relationships in the figure indicate top-down control? Which relationships indicate bottom-up control?

Keystone species

What do the data in the graphs suggest about the resistance of the community to disturbance?

Whitaker's classic study of trees in the Great Smoky Mountains provided evidence of the fact that

Introduction: Ecology, Evolution, and the Scientific Method

Adaptations to Aquatic Environments

Adaptations to Terrestrial Environments

Adaptations to Variable Environments

Climates and Soils

Terrestrial and Aquatic Biomes

Evolution and Adaptation

Life Histories

Reproductive Strategies

Social Behaviors

Population Distributions

Population Growth and Regulation

Population Dynamics Over Space and Time

Predation and Herbivory

Parasitism and Infectious Diseases

Competition

Mutualism

Community Succession

Movement of Energy in Ecosystems

Movement of Elements in Ecosystems

Landscape Ecology and Global Biodiversity

Global Conservation of Biodiversity

Filters

Exam 18: Community Structure

How does an ecologist determine the presence of an ecotone?

Which relationships in the figure indicate top-down control? Which relationships indicate bottom-up control?

Keystone species

What do the data in the graphs suggest about the resistance of the community to disturbance?

Whitaker's classic study of trees in the Great Smoky Mountains provided evidence of the fact that

Introduction: Ecology, Evolution, and the Scientific Method

Adaptations to Aquatic Environments

Adaptations to Terrestrial Environments

Adaptations to Variable Environments

Climates and Soils

Terrestrial and Aquatic Biomes

Evolution and Adaptation

Life Histories

Reproductive Strategies

Social Behaviors

Population Distributions

Population Growth and Regulation

Population Dynamics Over Space and Time

Predation and Herbivory

Parasitism and Infectious Diseases

Competition

Mutualism

Community Succession

Movement of Energy in Ecosystems

Movement of Elements in Ecosystems

Landscape Ecology and Global Biodiversity

Global Conservation of Biodiversity

Filters

Exam 18: Community Structure　