The video explains the concept of keystone species, highlighting their crucial role in ecosystems. It discusses the impact of grey wolves in Yellowstone, showing how their presence or absence affects the entire ecosystem. The role of elephants in forest management is explored, emphasizing their contribution to biodiversity. Finally, the importance of parrotfish in maintaining healthy coral reefs is discussed, stressing the need for conservation efforts.

What is a keystone species, and why is it important in an ecosystem?

• A species that is the largest predator in an ecosystem.

• A species that is the most colorful in an ecosystem.

• A species that has a large impact on its environment relative to its abundance.

• A species that is the most numerous in an ecosystem.

How did the reintroduction of wolves affect the elk population in Yellowstone?

• Elk numbers were unaffected by the wolves.

• Elk numbers initially declined but later stabilized.

• Elk numbers remained unchanged.

• Elk numbers increased significantly.

In what way do elephants contribute to forest biodiversity?

• By preventing other animals from entering the forest.

• By eating only one type of plant.

• By creating open spaces and light shafts for other plants.

• By planting new trees.

What role do parrotfish play in maintaining coral reef health?

• They provide food for larger fish species.

• They build coral reefs.

• They eat coral, helping it grow faster.

• They control algae growth, preventing it from smothering coral.

Why is it important to protect parrotfish in the Caribbean?

• They are the largest fish in the reef.

• They are the most colorful fish in the reef.

• They are a major food source for humans.

• They help keep coral reefs resilient against environmental stressors.