Question 1

Considering the traditional view of ecological succession, which plant would most likely be a pioneer species in a primary succession event?​
A) ​an oak tree that produces acorns dispersed by squirrels
B) ​a snapdragon flower pollinated by bees
C) ​a dandelion that produces seeds asexually, which are dispersed by the wind
D) ​a perennial species such as Douglas fir trees
E) a birch tree​

Accepted Answer

Pioneer species in primary succession are typically those that can colonize bare, lifeless environments, such as newly formed volcanic islands or areas stripped by glaciers. They must be hardy, able to reproduce asexually or have seeds that are easily dispersed without the need for a developed ecosystem. Dandelions (C) fit this description well because they produce seeds that can be dispersed by the wind, allowing them to quickly colonize new areas.

Question 2

The cowbird chick with its foster parent exemplifies an example of ____.​
A) ​commensalism
B) ​brood parasitism
C) ​competition
D) ​mutualism
E) parasitoidism​

Accepted Answer

Cowbird chicks exemplify brood parasitism because they are laid in the nests of other bird species, which then raise the cowbird chick often at the expense of their own offspring.

Question 3

An example of a specific adaptation against predation is ____.​
A) ​photosynthetic dinoflagellates providing sugars to corals
B) ​eagles and foxes fighting over a carcass
C) ​two species of Paramecium feeding on bacteria
D) ​sundew plants and wolf spiders competing for food
E) ​a skunk squirting foul-smelling, irritating repellents

Accepted Answer

Skunks have developed the ability to squirt a foul-smelling and irritating substance as a specific adaptation to deter predators, making choice E the correct answer.

Question 4

This orchid attached to a tree branch is an example of ____. 
A) competition
B) parasitism
C) predation
D) commensalism
E) mutualism

Accepted Answer

The answer of This orchid attached to a tree branch...

Question 5

An example of keystone species are ____.​
A) ​beavers that build dams
B) ​mice that feed on mushrooms and truffles
C) ​Douglas fir trees
D) ​kudzu
E) earthworms that aid decomposition​

Accepted Answer

Beavers are considered a keystone species because their dam-building activities create wetlands, which provide habitats for many other species and significantly alter the ecosystem.

Question 6

Which is a factor in determining which plant type becomes the pioneer species in a primary succession event?​
A) ​the species of plants that preceded it
B) ​the animals that occupy the area
C) ​chance events that affect the order in which pioneer species arrive
D) ​the nature of the existing soils
E) the type of disturbance​

Accepted Answer

Pioneer species in a primary succession event are often determined by chance events that affect the order in which they arrive, as there is no existing soil or ecosystem to influence their establishment initially.

Question 7

The plants and animals present in a region from which the trees were removed ten years earlier represent ____.​
A) ​primary succession
B) ​a climax forest
C) ​pioneer species
D) ​secondary succession
E) species introduction​

Accepted Answer

Secondary succession occurs in areas where a disturbance has removed the vegetation but has left the soil intact, such as in regions where trees were removed.

Question 8

Tapeworms and flukes are examples of ____.​
A) ​commensalism
B) ​mutualism
C) ​competition
D) ​predation
E) parasitism​

Accepted Answer

Tapeworms and flukes are examples of parasitism, where they live in or on a host organism and benefit at the host's expense.

Question 9

Hoverflies like to drop in at outdoor picnics to sample the sweets, but the reaction of humans is to flee the scene because of the flies' uncanny resemblance to bees. Thus, the survival of hoverflies is enhanced by ____.
A) mimicry
B) display behavior
C) warning coloration
D) chemical defenses
E) camouflage

Accepted Answer

Mimicry enhances the survival of hoverflies because their resemblance to bees, which are often perceived as dangerous due to their ability to sting, deters predators, including humans, from attacking them.

Question 10

This image shows an area in which a glacier has melted. What is indicated by the number "2"? 
A) competition for food resources
B) resource partitioning between two competing species
C) emergence of climax species
D) colonization by pioneer species
E) secondary succession

Accepted Answer

The answer of This image shows an area in which...

Question 11

Phorid flies lay their eggs inside the bodies of various insects and spiders. When the larvae hatch, they consume the body of the "host" from the inside out. The phorid fly is an example of a ____.
A) brood parasite
B) parasitoid
C) commensalist
D) competitive excluder
E) mutualist

Accepted Answer

Phorid flies are considered parasitoids because their larvae live as parasites inside a host organism and ultimately kill the host, which is characteristic of parasitoid behavior.

Question 12

How are parasitoids different from typical brood parasites?
A) They are usually not insects.
B) They affect only plants.
C) They lay eggs inside a host, which is eventually killed.
D) They fool another species into caring for their young.
E) They usually only affect the eggs of birds.

Accepted Answer

Parasitoids, unlike typical brood parasites, lay their eggs inside or on a host organism, and the developing larva eventually kills the host. This is a key characteristic that differentiates them from brood parasites, which typically lay their eggs in the nests of other species, relying on the host to raise their young without directly killing the host.

Question 13

Secondary succession can occur ____.​
A) ​after a fire
B) ​on a new sand dune
C) ​on bare rock
D) ​immediately after the formation of an artificial lake
E) ​on a glacier

Accepted Answer

Secondary succession occurs in areas where a disturbance has happened but soil is still present, such as after a fire. Choices B, C, D, and E describe scenarios where primary succession would occur, as they involve environments where soil needs to be developed first.

Question 14

Two species of closely related squirrels both feed on acorns produced by oak trees. One species feeds exclusively near the top of the tree and the other feeds exclusively toward the bottom of the tree. This is an example of ____.
A) competitive exclusion
B) resource partitioning
C) mutualism
D) commensalism
E) mimicry

Accepted Answer

This is an example of resource partitioning, where two species divide a resource based on differences in their behavior or morphology, allowing them to coexist by reducing direct competition for the same resources.

Question 15

The first plant to colonize the plains of Mount Saint Helens after this volcano erupted in 1980 was a prairie lupine. The prairie lupine is therefore an example of ____.​
A) ​a secondary successor
B) ​a pioneer species
C) ​a keystone species
D) ​an exotic species
E) an introduced species​

Accepted Answer

Prairie lupine, as the first plant to colonize the plains of Mount Saint Helens after the eruption, is an example of a pioneer species. Pioneer species are the first to colonize previously disrupted or damaged ecosystems, beginning a chain of ecological succession that ultimately leads to a more biodiverse steady-state ecosystem.

Question 16

Which represents an early stage in primary succession?​
A) ​pine tree growth
B) ​mosses and lichen on bare rock
C) ​weedy annual plants in an open field
D) ​climax species in succession
E) fields of food crops​

Accepted Answer

Mosses and lichen on bare rock represent an early stage in primary succession, as they are among the first organisms to colonize bare or newly exposed areas, beginning the process of soil formation.

Question 17

​Many introduced species have deleterious effects on communities and ecosystems because ____.
A) ​coevolved parasites and pathogens are absent
B) ​the introduced species are long-lived
C) ​predators prefer the introduced species, resulting in proliferation of native prey species
D) ​the community from which they came lost an important predator, competitor, or parasite
E) human beings do not know how to appreciate them​

Accepted Answer

Introduced species often lack their natural predators, competitors, or parasites in new environments, which can allow them to proliferate unchecked, often to the detriment of native species and ecosystems.

Question 18

The monarch butterfly is poisonous to birds; therefore, birds avoid eating them. Viceroy butterflies look very similar to monarch butterflies but are not poisonous. Because they look like monarch butterflies, birds also do not eat viceroy butterflies. This is an example of ____.
A) resource partitioning
B) competitive exclusion
C) mimicry
D) camouflage
E) commensalism

Accepted Answer

This is an example of mimicry, where the viceroy butterfly mimics the appearance of the poisonous monarch butterfly to avoid predation, even though viceroys themselves are not poisonous.

Question 19

Which is an example of an event that would give rise to primary succession?​
A) ​a dense landslide of mountain rocks covering an entire valley
B) ​a fire that burns all surface vegetation
C) ​an abandoned agricultural field
D) ​a lake that dries up, killing all aquatic plants
E) a forest that is logged​

Accepted Answer

Primary succession occurs in lifeless areas where there is no soil to begin with. A dense landslide covering an entire valley would remove the soil and create such a condition, making it an example of an event leading to primary succession.

Question 20

Commensalism is a type of ____.​
A) ​predation
B) ​symbiosis
C) active competition​
D) ​scramble competition
E) competitive exclusion​

Accepted Answer

Commensalism is a type of symbiosis where one organism benefits from the relationship and the other is neither helped nor harmed.

Quiz 18: Communities and Ecosystems

Considering the traditional view of ecological succession, which plant would most likely be a pioneer species in a primary succession event?​

The cowbird chick with its foster parent exemplifies an example of ____.​

An example of a specific adaptation against predation is ____.​

This orchid attached to a tree branch is an example of ____.

An example of keystone species are ____.​

Which is a factor in determining which plant type becomes the pioneer species in a primary succession event?​

The plants and animals present in a region from which the trees were removed ten years earlier represent ____.​

Tapeworms and flukes are examples of ____.​

Hoverflies like to drop in at outdoor picnics to sample the sweets, but the reaction of humans is to flee the scene because of the flies' uncanny resemblance to bees. Thus, the survival of hoverflies is enhanced by ____.

This image shows an area in which a glacier has melted. What is indicated by the number "2"?

Phorid flies lay their eggs inside the bodies of various insects and spiders. When the larvae hatch, they consume the body of the "host" from the inside out. The phorid fly is an example of a ____.

How are parasitoids different from typical brood parasites?

Secondary succession can occur ____.​

Two species of closely related squirrels both feed on acorns produced by oak trees. One species feeds exclusively near the top of the tree and the other feeds exclusively toward the bottom of the tree. This is an example of ____.

The first plant to colonize the plains of Mount Saint Helens after this volcano erupted in 1980 was a prairie lupine. The prairie lupine is therefore an example of ____.​

Which represents an early stage in primary succession?​

​Many introduced species have deleterious effects on communities and ecosystems because ____.

The monarch butterfly is poisonous to birds; therefore, birds avoid eating them. Viceroy butterflies look very similar to monarch butterflies but are not poisonous. Because they look like monarch butterflies, birds also do not eat viceroy butterflies. This is an example of ____.

Which is an example of an event that would give rise to primary succession?​

Commensalism is a type of ____.​

Considering the traditional view of ecological succession, which plant would most likely be a pioneer species in a primary succession event?

The cowbird chick with its foster parent exemplifies an example of ____.

An example of a specific adaptation against predation is ____.

An example of keystone species are ____.

Which is a factor in determining which plant type becomes the pioneer species in a primary succession event?

The plants and animals present in a region from which the trees were removed ten years earlier represent ____.

Tapeworms and flukes are examples of ____.

Secondary succession can occur ____.

The first plant to colonize the plains of Mount Saint Helens after this volcano erupted in 1980 was a prairie lupine. The prairie lupine is therefore an example of ____.

Which represents an early stage in primary succession?

Many introduced species have deleterious effects on communities and ecosystems because ____.

Which is an example of an event that would give rise to primary succession?

Commensalism is a type of ____.