Trophic Cascades and Keystone Species

A side-effect when a certain species that usually helps to keep the entire ecosystem balanced is reduced or removed. When their numbers are changed there is an ecological imbalance.

• trophic level

• trophic cascade

• food web

• food chain

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-2

NGSS.MS-LS2-4

Which of the following are true about a keystone species?

• Is the GLUE that holds an ecosystem together.

• If it is removed, it will impact the structure and biodiversity of a habitat/ecostyem.

• It has NO impact on other organisms in an ecosystem.

• There is only 1 keystone species in every ecosystem.

Tags

NGSS.MS-LS2-2

NGSS.MS-LS2-4

NGSS.MS-LS2-5

A keystone species that is a critical food source for predator populations. For example, krill.

• keystone predator

• keystone prey

• keystone ecosystem engineer

• keystone plant

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

NGSS.MS-LS2-4

A keystone species that create, modify, or maintain the landscape around them. For example, a beaver.

• keystone predator

• keystone prey

• keystone ecosystem engineer

• keystone plant

Tags

NGSS.MS-LS2-4

What are the effects of removing top predators from an ecosystem?

• Increased biodiversity

• Decreased population of primary producers

• Increased population of primary consumers

• No significant impact

Tags

DOK Level 2: Skill/Concept

Explain how the removal of a keystone species can lead to a trophic cascade.

• The removal of a keystone species can lead to a trophic cascade by disrupting the balance of the ecosystem, causing a chain reaction that affects multiple trophic levels.

• The removal of a keystone species has no effect on trophic cascades.

• The removal of a keystone species only affects the primary producers.

• The removal of a keystone species only affects the top predators.

Tags

DOK Level 3: Strategic Thinking

Investigate how the introduction of a new keystone species might affect an existing ecosystem.

• The introduction of a new keystone species will have no effect on the ecosystem

• The introduction of a new keystone species can disrupt the existing balance, potentially leading to changes in population dynamics and ecosystem structure

• The introduction of a new keystone species will only affect the primary producers

• The introduction of a new keystone species will only affect the top predators

Tags

DOK Level 4: Extended Thinking

Which of the following is an example of a trophic cascade?

• A decrease in the population of primary consumers leading to an increase in primary producers

• An increase in the population of top predators leading to a decrease in primary producers

• A change in weather patterns affecting the entire ecosystem

• The introduction of a new plant species into an ecosystem

Tags

DOK Level 2: Skill/Concept

Synthesize information from multiple sources to explain how human activities can lead to trophic cascades.

• Human activities have no effect on trophic cascades

• Human activities such as overfishing, deforestation, and pollution can disrupt the balance of ecosystems, leading to trophic cascades that affect multiple trophic levels

• Human activities only affect primary producers

• Human activities only affect top predators

Tags

DOK Level 4: Extended Thinking

A keystone species that keeps populations under control by hunting. This also impacts other species further down the food chain.

• keystone predator

• keystone prey

• keystone ecosystem engineer

• keystone plant

Tags

NGSS.MS-LS2-4