Question 1

Which statement about Patterson's study of the distributions of Tamias chipmunks in the southwestern United States is false?

Accepted Answer

A)  It found that in mountain ranges where two species were present, the overlap of their distributions was small. 
B)  It found that in mountain ranges where only one species was present, that species was found over a broader distribution of habitats than would have been possible in the presence of a competitor. 
C)  They were manipulative experiments. 
D)  They suggested that competition is limiting the ranges of the species. 
A)  It found that in mountain ranges where two species were present, the overlap of their distributions was small. 
B)  It found that in mountain ranges where only one species was present, that species was found over a broader distribution of habitats than would have been possible in the presence of a competitor. 
C)  They were manipulative experiments. 
D)  They suggested that competition is limiting the ranges of the species.

Question 2

The critical feature determining whether a substance is a resource is whether it

Accepted Answer

A)  is abiotic or biotic. 
B)  is required by an organism. 
C)  is required for growth. 
D)  can be used to produce ATP. 
A)  is abiotic or biotic. 
B)  is required by an organism. 
C)  is required for growth. 
D)  can be used to produce ATP.

Question 3

A population of Drosophila melanogaster with 10,000 individuals and a carrying capacity of 20,000 follows the logistic growth equation. Suppose that 5,000 individuals of a competitor species, Drosophila simulans, are added to the population, and that this species has an α of 0.5. One would predict that this number of competitive individuals will decrease the D. melanogaster population growth rate by the same amount as the addition of _______ D. melanogaster individuals would.

Accepted Answer

A)  250 
B)  750 
C)  1,000 
D)  2,500 
A)  250 
B)  750 
C)  1,000 
D)  2,500

Question 4

The dominant saltmeadow cordgrass (Spartina patens) was planted across an elevation gradient around a stress-tolerant low marsh species, smooth cordgrass (S. alterniflora). Within six months, S. alterniflora had suppressed the stature and growth of S. patens. This is an example of

Accepted Answer

A)  competitive reversal. 
B)  competitive exclusion. 
C)  niche partitioning. 
D)  fugitive species interactions. 
A)  competitive reversal. 
B)  competitive exclusion. 
C)  niche partitioning. 
D)  fugitive species interactions.

Question 5

Two species of sparrows are competing, and these species behave according to the Lotka‒Volterra equations. If each individual sparrow reduces the population growth rate of its own species by 0.02 per year, and it reduces the population growth rate of the other species by 0.005 per year, then the competition coefficient is

Accepted Answer

A)  0.005. 
B)  0.02. 
C)  0.25. 
D)  0.4. 
A)  0.005. 
B)  0.02. 
C)  0.25. 
D)  0.4.

Question 6

Brown and Davidson's study of a desert community showed that

Accepted Answer

A)  there is substantial overlap in the seeds eaten by ants and rodents. 
B)  exclusion of rodents leads to a decrease of ant colonies. 
C)  exclusion of both ants and rodents has little effect on the availability of seeds. 
D)  rodents and ants prefer different size seeds. 
A)  there is substantial overlap in the seeds eaten by ants and rodents. 
B)  exclusion of rodents leads to a decrease of ant colonies. 
C)  exclusion of both ants and rodents has little effect on the availability of seeds. 
D)  rodents and ants prefer different size seeds.

Question 7

How did Brewer manipulate the level of competition in his experiment on pitcher plants?

Accepted Answer

A)  By adding noncarnivorous competitor species 
B)  By weeding and clipping noncarnivorous competitor species 
C)  By adding ants 
D)  By removing ants 
A)  By adding noncarnivorous competitor species 
B)  By weeding and clipping noncarnivorous competitor species 
C)  By adding ants 
D)  By removing ants

Question 8

Which statement about carnivorous plants is false?

Accepted Answer

A)  Many carnivorous plants are found only in environments where soils are poor in nutrients. 
B)  Carnivorous plants like Venus flytraps occasionally consume relatively large animals, including frogs and slugs. 
C)  Carnivorous plants typically have very extensive root systems. 
D)  Many pitcher plants have an internal layer of flaky wax that assists in prey capture. 
A)  Many carnivorous plants are found only in environments where soils are poor in nutrients. 
B)  Carnivorous plants like Venus flytraps occasionally consume relatively large animals, including frogs and slugs. 
C)  Carnivorous plants typically have very extensive root systems. 
D)  Many pitcher plants have an internal layer of flaky wax that assists in prey capture.

Question 9

Which observation would be the strongest evidence that character displacement is occurring?

Accepted Answer

A)  Competing species are more morphologically similar when apart than when they are together. 
B)  The outcome of competition reverses after a period of time. 
C)  Within species, individuals that resemble their competitors the most have a selective advantage. 
D)  Within species, individuals that resemble their competitors the most have a selective disadvantage. 
A)  Competing species are more morphologically similar when apart than when they are together. 
B)  The outcome of competition reverses after a period of time. 
C)  Within species, individuals that resemble their competitors the most have a selective advantage. 
D)  Within species, individuals that resemble their competitors the most have a selective disadvantage.

Question 10

Dragonfly species A (with a carrying capacity of 1,000) and species B (with a carrying capacity of 400) are competing. The competition coefficient of species A on species B is 0.25, and the competition coefficient of species B on species A is 0.5. Dragonfly species C (with a carrying capacity of 5,000) and species D (with a carrying capacity of 10,000) are also competing. The competition coefficient of species C on species D is 0.1, and the competition coefficient of species D on species C is 0.2. Based on the Lotka‒Volterra equation, which of these pairs of species can coexist?

Accepted Answer

A)  Only species A and species B 
B)  Only species C and species D 
C)  Both pairs of species can coexist. 
D)  Neither pair of species can coexist. 
A)  Only species A and species B 
B)  Only species C and species D 
C)  Both pairs of species can coexist. 
D)  Neither pair of species can coexist.

Question 11

Which of the following is not an example of a resource?

Accepted Answer

A)  A stenocara beetle captures water from fog that condenses on its back 
B)  An increase in temperature increases aggressiveness in a species of coral reef fish. 
C)  Dung beetles collect and store dung to be used as a food source for their larva 
D)  A bumblebee collects nectar from a flowering plant 
A)  A stenocara beetle captures water from fog that condenses on its back 
B)  An increase in temperature increases aggressiveness in a species of coral reef fish. 
C)  Dung beetles collect and store dung to be used as a food source for their larva 
D)  A bumblebee collects nectar from a flowering plant

Question 12

Which statement about studies on the importance of competition in nature is false?

Accepted Answer

A)  Nearly all studies find the occurrence of competition; competition is ubiquitous in nature. 
B)  Many studies find the occurrence of competition; competition is common in nature. 
C)  Analyses of the studies identified several possible sources of bias, including the failure of researchers to publish studies that show no significant results. 
D)  Many studies were biased because they overly represented species that were suspected to show competition. 
A)  Nearly all studies find the occurrence of competition; competition is ubiquitous in nature. 
B)  Many studies find the occurrence of competition; competition is common in nature. 
C)  Analyses of the studies identified several possible sources of bias, including the failure of researchers to publish studies that show no significant results. 
D)  Many studies were biased because they overly represented species that were suspected to show competition.

Question 13

Two species of ground crickets compete in the eastern United States. In colder areas, Allonemobius fasciatus outcompetes Allonemobius socius, but in warm areas, A. socius outcompetes A. fasciatus. This is an example of

Accepted Answer

A)  a competitive reversal. 
B)  allelopathy. 
C)  a conspecific precedence. 
D)  a character displacement. 
A)  a competitive reversal. 
B)  allelopathy. 
C)  a conspecific precedence. 
D)  a character displacement.

Question 14

Use inequalities generated by the Lotka-Volterra competition model to determine whether two species of Paramecium (P. caudatum is "species 1" and P. aurelia is "species 2") will coexist or drive each other to extinction in the three scenarios below. In these examples, N1 = N2, and K1 = K2 = 50.
Scenario 1: Determine the outcome of the competitive interaction between P. caudatum and P. aurelia if F1F1F1S1$\alpha$F1F1F10 = 0.3, and F1F1F1S1$\beta$F1F1F10 = 0.6.
Scenario 2: Determine the outcome of the competitive interaction between P. caudatum and P. aurelia if F1F1F1S1$\alpha$F1F1F10 = 1.5, and F1F1F1S1$\beta$F1F1F10 = 0.6.
Determine the outcome of competition between the species under scenario 2.Answer the following questions:
a) Do the two species coexist?
b) Does one species drive the other to extinction? If so, which goes extinct?

Accepted Answer

a) No, the two species do not

Question 15

Which of the following findings from Connell's experiments with intertidal barnacles is false?

Accepted Answer

A)  In both species, the extent of the distribution of larvae is greater than that of adults. 
B)  One species is excluded from the top of the intertidal zone due to sensitivity to desiccation. 
C)  One species is excluded from the bottom of the intertidal zone due to competition with the other species. 
D)  Both species of barnacles survived better when tidal disturbances removed patches of competitive mussels. 
A)  In both species, the extent of the distribution of larvae is greater than that of adults. 
B)  One species is excluded from the top of the intertidal zone due to sensitivity to desiccation. 
C)  One species is excluded from the bottom of the intertidal zone due to competition with the other species. 
D)  Both species of barnacles survived better when tidal disturbances removed patches of competitive mussels.

Question 16

Refer to the figure.
  Based on the figure, what is the expected outcome of the competition between species 1 and species 2?

Accepted Answer

A)  Coexistence 
B)  Competitive exclusion of species 2 by species 1 
C)  Competitive exclusion of species 1 by species 2 
D)  Persistence of one species only; whichever one persists will depend on the initial conditions 
A)  Coexistence 
B)  Competitive exclusion of species 2 by species 1 
C)  Competitive exclusion of species 1 by species 2 
D)  Persistence of one species only; whichever one persists will depend on the initial conditions

Question 17

A fundamental niche

Accepted Answer

A)  is always the same as a realized niche. 
B)  can only be altered if excess food is available to an organism. 
C)  is often not realized because no one species has exclusive access to all the resources within its fundamental niche. 
D)  is unrestricted by species-species interactions. 
A)  is always the same as a realized niche. 
B)  can only be altered if excess food is available to an organism. 
C)  is often not realized because no one species has exclusive access to all the resources within its fundamental niche. 
D)  is unrestricted by species-species interactions.

Question 18

Refer to the figure.
  A population of sea palms in year 1 has a density of 80 N/m2. The predicted density expected in year 2 is _______ N/m2 which is _______ the exact replacement curve.

Accepted Answer

A)  60; below 
B)  19; above 
C)  19; below 
D)  80; below 
A)  60; below 
B)  19; above 
C)  19; below 
D)  80; below

Question 19

Competitive exclusion states that two organisms cannot indefinitely occupy the same niche when resources are limited. When this does occur, organisms tend to show some sort of competitive coexistence. Which of the following is an example of competitive exclusion?

Accepted Answer

A)  Songbirds pick different nesting sites. 
B)  Manatees consume all the native grasses in a lagoon. 
C)  Oak trees and pine trees live in the same forest. 
D)  Wildebeests and zebras graze on the same savannah. 
A)  Songbirds pick different nesting sites. 
B)  Manatees consume all the native grasses in a lagoon. 
C)  Oak trees and pine trees live in the same forest. 
D)  Wildebeests and zebras graze on the same savannah.

Question 20

Suppose that, instead of the results actually obtained in Brown and Davidson's experiments, the number of rodents in the ant-excluded treatment was roughly the same as the number of rodents in the control group, and the number of ants in the rodent-excluded treatment was roughly the same as the number of ants in the control group. Which of the following would you then conclude?

Accepted Answer

A)  Competition is asymmetrical, with rodents affecting ants more than ants affect rodents. 
B)  The two species have reduced competition through resource partitioning. 
C)  Competition is asymmetrical, with rodents affecting ants less than ants affect rodents. 
D)  There has been a competitive reversal. 
A)  Competition is asymmetrical, with rodents affecting ants more than ants affect rodents. 
B)  The two species have reduced competition through resource partitioning. 
C)  Competition is asymmetrical, with rodents affecting ants less than ants affect rodents. 
D)  There has been a competitive reversal.

Which statement about Patterson's study of the distributions of Tamias chipmunks in the southwestern United States is false?

The critical feature determining whether a substance is a resource is whether it

The dominant saltmeadow cordgrass (Spartina patens) was planted across an elevation gradient around a stress-tolerant low marsh species, smooth cordgrass (S. alterniflora). Within six months, S. alterniflora had suppressed the stature and growth of S. patens. This is an example of

Brown and Davidson's study of a desert community showed that

How did Brewer manipulate the level of competition in his experiment on pitcher plants?

Which statement about carnivorous plants is false?

Which observation would be the strongest evidence that character displacement is occurring?

Which of the following is not an example of a resource?

Which statement about studies on the importance of competition in nature is false?

Two species of ground crickets compete in the eastern United States. In colder areas, Allonemobius fasciatus outcompetes Allonemobius socius, but in warm areas, A. socius outcompetes A. fasciatus. This is an example of

Which of the following findings from Connell's experiments with intertidal barnacles is false?

Refer to the figure. Based on the figure, what is the expected outcome of the competition between species 1 and species 2?

A fundamental niche

Refer to the figure. A population of sea palms in year 1 has a density of 80 N/m². The predicted density expected in year 2 is _ N/m²which is _ the exact replacement curve.

Competitive exclusion states that two organisms cannot indefinitely occupy the same niche when resources are limited. When this does occur, organisms tend to show some sort of competitive coexistence. Which of the following is an example of competitive exclusion?

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Exam 14: Competition

Which statement about Patterson's study of the distributions of Tamias chipmunks in the southwestern United States is false?

The critical feature determining whether a substance is a resource is whether it

The dominant saltmeadow cordgrass (Spartina patens) was planted across an elevation gradient around a stress-tolerant low marsh species, smooth cordgrass (S. alterniflora). Within six months, S. alterniflora had suppressed the stature and growth of S. patens. This is an example of

Brown and Davidson's study of a desert community showed that

How did Brewer manipulate the level of competition in his experiment on pitcher plants?

Which statement about carnivorous plants is false?

Which observation would be the strongest evidence that character displacement is occurring?

Which of the following is not an example of a resource?

Which statement about studies on the importance of competition in nature is false?

Two species of ground crickets compete in the eastern United States. In colder areas, Allonemobius fasciatus outcompetes Allonemobius socius, but in warm areas, A. socius outcompetes A. fasciatus. This is an example of

Which of the following findings from Connell's experiments with intertidal barnacles is false?

Refer to the figure. Based on the figure, what is the expected outcome of the competition between species 1 and species 2?

A fundamental niche

Refer to the figure. A population of sea palms in year 1 has a density of 80 N/m2. The predicted density expected in year 2 is _______ N/m2 which is _______ the exact replacement curve.

Competitive exclusion states that two organisms cannot indefinitely occupy the same niche when resources are limited. When this does occur, organisms tend to show some sort of competitive coexistence. Which of the following is an example of competitive exclusion?

The Web of Life

The Physical Environment

The Biosphere

Coping With Environmental Variation:

Coping With Environmental Variation: Energy

Evolution and Ecology

Life History

Behavioral Ecology

Population Distribution and Abundance

Population Dynamics

Population Growth and Regulation

Predation

Parasitism

Mutualism and Commensalism

The Nature of Communities

Change in Communities

Biogeography

Species Diversity in Communities

Production

Energy Flow and Food Webs

Nutrient Supply and Cycling

Conservation Biology

Landscape Ecology and Ecosystem Management

Global Ecology

Filters

Refer to the figure. A population of sea palms in year 1 has a density of 80 N/m². The predicted density expected in year 2 is _ N/m²which is _ the exact replacement curve.