AP Environmental Science Practice Quiz: Ecological Succession

Written by AP Content Team, Verified for 2026 AP Exams, Last updated: May 2026

Test your understanding with short quizzes. This quiz has 16 questions to check your progress.

Question 1 of 16

Which of the following best describes the process of ecological succession?

A)The daily interaction between predator and prey within a stable community.B)The gradual change in the species composition and community structure of an ecosystem over time.C)The immediate recovery of an ecosystem to its original state after a disturbance.D)The adaptation of a single organism to a new environmental condition.

All Questions (16)

Which of the following best describes the process of ecological succession?

A) The daily interaction between predator and prey within a stable community.

B) The gradual change in the species composition and community structure of an ecosystem over time.

C) The immediate recovery of an ecosystem to its original state after a disturbance.

D) The adaptation of a single organism to a new environmental condition.

Correct Answer: B

Based on the provided content, ecological succession is the process by which an ecosystem's structure changes over time. This involves shifts in the types and numbers of species present.

According to the provided text, what are the two main types of ecological succession?

A) Aquatic and Terrestrial

B) Pioneer and Keystone

C) Primary and Secondary

D) Rapid and Gradual

Correct Answer: C

The text explicitly states, 'There are two main types of ecological succession: primary and secondary succession.'

A species whose activities have a disproportionately large effect on its community's structure is defined as a(n):

A) Pioneer species

B) Indicator species

C) Keystone species

D) Successional species

Correct Answer: C

The content defines a keystone species as one 'whose activities have a particularly significant role in determining community structure.'

The presence of a specific lichen on a tree indicates very low levels of air pollution. Based on the text, this lichen is best described as a(n):

A) Indicator species

B) Keystone species

C) Pioneer species

D) Primary species

Correct Answer: A

The text defines an indicator species as a plant or animal whose presence demonstrates a 'distinctive aspect of the character or quality of an ecosystem.' In this case, the lichen indicates air quality.

Which term applies to the first organisms that commonly colonize an unoccupied habitat?

A) Keystone members

B) Indicator members

C) Secondary successors

D) Pioneer members

Correct Answer: D

The provided content states, 'Pioneer members of an early successional species commonly move into unoccupied habitat.'

According to the provided text, what is a potential long-term consequence of pioneer species adapting to a new habitat over time?

A) They will always become the keystone species of the new ecosystem.

B) The ecosystem will revert to its pre-disturbance state immediately.

C) The origin of new species may occur.

D) The total biomass of the ecosystem will permanently decrease.

Correct Answer: C

The text directly states that pioneer species 'adapt over time, which may result in the origin of new species.'

Following a major disturbance like a wildfire, ecological succession will affect which of the following ecosystem characteristics over time?

A) The geographic coordinates of the ecosystem.

B) Only the number of keystone species.

C) Total biomass, species richness, and net productivity.

D) The type of succession from secondary to primary.

Correct Answer: C

The content explicitly mentions, 'Succession in a disturbed ecosystem will affect the total biomass, species richness, and net productivity over time.'

What is the key difference between a keystone species and an indicator species as described in the text?

A) Keystone species are early colonizers, while indicator species appear in mature ecosystems.

B) Keystone species influence community structure, while indicator species reflect environmental quality.

C) Keystone species are always animals, while indicator species are always plants.

D) Keystone species increase net productivity, while indicator species increase biomass.

Correct Answer: B

This question requires synthesizing two definitions. The text defines keystone species by their role in 'determining community structure' and indicator species by their ability to demonstrate 'quality of an ecosystem.'

The process of ecological succession demonstrates that ecosystems are:

A) Static and unchanging once they reach maturity.

B) Entirely dependent on a single keystone species for survival.

C) Dynamic and change in composition and properties over time.

D) Incapable of recovering from any form of disturbance.

Correct Answer: C

The core concept of succession is change over time. The text describes this change and its effects on biomass, species richness, and productivity, all of which point to the dynamic nature of ecosystems.

A volcanic eruption creates a new island of bare rock. The subsequent development of an ecosystem on this island is an example of which process?

A) Secondary succession, led by indicator species.

B) Community structuring by a keystone species.

C) Primary succession, initiated by pioneer species.

D) A decrease in net productivity over time.

Correct Answer: C

This scenario describes the colonization of a completely new, unoccupied habitat (bare rock). This is the definition of primary succession, which is started by pioneer members moving into the habitat.

Which of the following lists includes three factors that are all affected by ecological succession?

A) Climate, longitude, and keystone species.

B) Total biomass, species richness, and net productivity.

C) Pioneer species, secondary succession, and habitat size.

D) Indicator species, latitude, and soil type.

Correct Answer: B

The text directly states that succession affects 'the total biomass, species richness, and net productivity over time.'

If the removal of sea otters from a kelp forest ecosystem causes a collapse of the kelp and the species that depend on it, the sea otter is acting as a(n):

A) Indicator species, because its absence indicates a problem.

B) Pioneer species, because it structures the early ecosystem.

C) Keystone species, because its activities determine community structure.

D) Successional species, because it is part of the ecosystem's changes.

Correct Answer: C

The significant impact of the sea otter's removal on the entire community structure is the defining characteristic of a keystone species as described in the provided text.

The main role of a pioneer species in ecological succession is to:

A) Represent the final, stable stage of an ecosystem.

B) Indicate the overall health or quality of the environment.

C) Move into and adapt to previously unoccupied habitats.

D) Maintain the structure of the entire biological community.

Correct Answer: C

The content specifies that 'Pioneer members of an early successional species commonly move into unoccupied habitat and adapt over time.'

An abandoned farm field begins to grow over with weeds and shrubs. This is an example of:

A) Primary succession, because new species are originating.

B) Secondary succession, because the ecosystem is recovering from a disturbance in an area that already has soil.

C) The establishment of a keystone species.

D) The use of an indicator species to measure biomass.

Correct Answer: B

Secondary succession occurs in areas that have been disturbed but still retain soil and some life. An abandoned farm field fits this description, distinguishing it from primary succession which starts on bare surfaces.

Which statement accurately synthesizes the information about species roles and succession?

A) Only keystone species can be pioneer species.

B) Indicator species are responsible for driving the process of secondary succession.

C) Pioneer species initiate succession in unoccupied habitats, while keystone species may be crucial for maintaining structure in later stages.

D) Primary succession and secondary succession are determined by the presence of indicator species.

Correct Answer: C

This answer correctly combines the definitions. Pioneer species are defined by their role in early succession in unoccupied habitats. Keystone species are defined by their structural importance, which can be a factor at any stage, but is often most apparent in more developed communities.

Over the course of both primary and secondary succession, an ecosystem will generally experience changes in its:

A) Fundamental classification from terrestrial to aquatic.

B) Species richness and total biomass.

C) Dependence on a single pioneer species.

D) Geographic location on the continent.

Correct Answer: B

The text states that succession affects total biomass and species richness. This is a fundamental outcome of the successional process, regardless of whether it is primary or secondary.