Chapter 5: Evolution and Community Ecology

Question 1

A landslide causes part of a mountainside to fall away, leaving bare rock. In the years immediately following the landslide, the area will experience

A.	primary succession.
B.	secondary succession.
C.	tertiary succession.
D.	a climax community.

Answer 1

A. primary succession.

Question 2

If these are present in a new environment, a species is unlikely to become invasive.

A.	predators, parasites, and competitors
B.	cane toads, kudzu, and zebra mussels
C.	exotic species
D.	symbiotic and commensalist species

Answer 2

A. predators, parasites, and competitors

Question 3

A reintroduced population of wolves in a national park is 90 percent grey and 10 percent black, consistent with the wolf population in other regions. After several generations in isolation, the national park’s wolf population is 60 percent grey and 40 percent black. The wolf population has likely experienced

A.	natural selection.
B.	genetic drift.
C.	mutations.
D.	migration.

Answer 3

B. genetic drift.

Question 4

In Madagascar, several species of lemur eat bamboo, but each species specializes in one part of the bamboo—one species eats mature bamboo stalks, one species eats bamboo shoots, and one species eats leaves. This is an example of

A.	speciation.
B.	resource partitioning.
C.	competition.
D.	niche partitioning.

Answer 4

B. resource partitioning.

Question 5

In the example above, one lemur species eats only bamboo shoots. Bamboo shoots contain a high level of cyanide, a toxic chemical. This lemur species has developed a tolerance for a certain amount of cyanide. What do you think will happen over time?

A. The level of cyanide in the bamboo population will increase.
B. The level of cyanide in the bamboo population will decrease.
C. The level of cyanide in the bamboo population will remain the same.
D. The level of cyanide in the lemur population will decrease.

Answer 5

A. The level of cyanide in the bamboo population will increase.

Question 6

When energy is transferred between trophic levels, the amount of available energy lost is about

A.	90 percent.
B.	50 percent..
C.	25 percent.
D.	10 percent.

Answer 6

A. 90 percent.

Question 7

Humans are generally

A.	carnivores.
B.	herbivores.
C.	omnivores.
D.	detritivores.

Answer 7

C. omnivores.

Question 8

Any being that uses the sun’s energy to create sugars is a

A.	primary producer.
B.	secondary producer.
C.	primary consumer.
D.	secondary consumer.

Answer 8

A. primary producer.

Question 9

Which best describes evolutionary success?

A. A successful organism possesses adaptive traits and is able to pass those traits on to numerous offspring which then reproduce.
B. A successful organism possesses traits that are different from traits in the rest of the population and that allow the organism to compete more successfully.
C. A successful organism produces more offspring than others in the population.
D. A successful organism possesses adaptive traits and produces more offspring that survive.

Answer 9

A. A successful organism possesses adaptive traits and is able to pass those traits on to numerous offspring which then reproduce.

Question 10

Around 65 million years ago, 95 percent of the planet’s species were wiped out, and the age of the dinosaurs ended. Which of the following best explains why we still have numerous species today?

A. The species that exist today were those that were not wiped out when the dinosaurs died.
B. The species that exist today evolved from surviving species to fill niches left vacant by the dinosaurs.
C. The species that exist today speciated due to separation among different populations.
D. The species that exist today have the potential to be as numerous as the ones that went extinct.

Answer 10

B. The species that exist today evolved from surviving species to fill niches left vacant by the dinosaurs.

Question 11

An invasive species is a species that has been introduced to a new area and lacks limiting factors.

True
False

Answer 11

True

Question 12

On islands off the coast of Siberia, paleontologists have found the remains of pygmy mammoths. These populations were likely separated from mainland mammoth populations and became a new type of mammoth through allopatric adaptation.

True
False

Answer 12

False (speciation)

Question 13

An organism that depends on another without killing it is a predator.

True
False

Answer 13

False (parasite)

Question 14

A nation where most of the people eat a primarily vegetarian diet will be able to support a lower population than it would if the people ate a lot of meat.

True
False

Answer 14

False (higher)

Question 15

In a woodland, a rabbit eats grass, and a coyote eats the rabbit. The coyote is a secondary consumer.

True
False

Answer 15

True

Question 16

In the years immediately after a fire, a forest will experience

A.	primary succession.
B.	secondary succession.
C.	tertiary succession.
D.	a climax community.

Answer 16

B. secondary succession.

Question 17

Which of the following best describes a successful individual in evolutionary terms?

A. A successful individual possesses traits that are different from the traits of the rest of the population.
B. A successful individual produces many offspring that possess unique traits.
C. A successful individual is well adapted to its environment and produces offspring that survive to pass on genes.
D. A successful individual will be well adapted to its environment and produce a few high quality offspring.

Answer 17

C. A successful individual is well adapted to its environment and produces offspring that survive to pass on genes.

Question 18

When the environment changes too quickly for an organism to adapt, what will occur?

A.	evolution
B.	speciation
C.	genetic drift
D.	extinction

Answer 18

D. extinction

Question 19

Two species of finch live in the same environment. Over time, one develops a larger beak to consume larger seeds, while the other develops a narrow beak to consume more delicate seeds. This is an example of

A.	resource partitioning.
B.	character displacement.
C.	coevolution.
D.	competitive exclusion.

Answer 19

A. resource partitioning.

Question 20

An interaction in which an individual of one species kills and consumes an individual of another is called

A.	predation.
B.	parasitism.
C.	herbivory.
D.	symbiosis.

Answer 20

A. predation.

Question 21

In the western United States, at the southern edge of their range, moose are sometimes so severely infested with ticks that they die. The tick/moose relationship is best described as

A.	predatory.
B.	parasitic.
C.	symbiotic.
D.	mutualistic.

Answer 21

B. parasitic.

Question 22

A beehive depends on pollen from flowers to survive. Flowers depend on bees to pollinate them. Humans tend bee hives, offering the bees a place to live in exchange for some of their honey. The relationship among these three sets of organisms is

A.	parasitic.
B.	commensalist.
C.	symbiotic.
D.	mutualistic.

Answer 22

D. mutualistic.

Question 23

The ultimate source of energy in an ecosystem in which deer eat grass and coyotes eat deer is

A.	the grass.
B.	the sun.
C.	the deer.
D.	chemosynthesis.

Answer 23

B. the sun.

Question 24

In a food web that consists of grass, mice, deer, coyotes, and hawks, which species is likely to have the greatest biomass?

A.	grass
B.	mice
C.	coyotes
D.	hawks

Answer 24

A. grass

Question 25

A niche restricted by competition is a

A.	fundamental niche.
B.	realized niche.
C.	resource partitioned niche.
D.	displaced niche.

Answer 25

B. realized niche.

Question 26

In the history of the world, how many mass extinctions have occurred?

A.	5
B.	7
C.	10
D.	13

Answer 26

A. 5

Question 27

In a mass extinction, the rate of extinction exceeds

A.	99%.
B.	85%.
C.	the rate of environmental change.
D.	the rate of background extinction.

Answer 27

D. the rate of background extinction.

Question 28

A deer browsing on a shrub is an example of

A.	predation.
B.	parasitism.
C.	herbivory.
D.	symbiosis.

Answer 28

C. herbivory.

Question 29

The first level of all food pyramids

A.	consists of primary producers.
B.	consists of primary consumers.
C.	is chemosynthesis.
D.	is photosynthesis.

Answer 29

A. consists of primary producers.

Question 30

A species with a restricted tolerance for environmental conditions is

A.	a specialist.
B.	a generalist.
C.	highly competitive.
D.	an autotroph.

Answer 30

A. a specialist.

Question 31

Two populations of a deer species are separated when a glacier forms. After the glacier melts, the two populations have become different species. This is an example of allopatric selection.

True
False

Answer 31

False (speciation)

Question 32

Communities that are powered by the sun depend on chemosynthesis for their energy.

True
False

Answer 32

False (photosynthesis)

Question 33

A food web cascade occurs when one species has an indirect effect on species at a different level of the energy pyramid.

True
False

Answer 33

False (trophic cascade)

Question 34

Animals gathering around a water hole in a drought-prone area and establishing hierarchies of access to the water is an example of competition.

True
False

Answer 34

True

Question 35

You have many species of bacteria living in your gut that help you with digestion. This relationship is best defined as commensalism.

True
False

Answer 35

False (mutualism)