Keystone Species

What defines a keystone species in biology?

• A species that is the largest in its habitat.

• A species that has a disproportionately large impact on its habitat, regardless of its size or numbers.

• A species that only affects other species indirectly.

• A species that is at the peak of a food chain.

How did the absence of wolves in Yellowstone National Park affect elk behavior?

• Elk became more aggressive towards other species.

• Elk started to migrate to different areas of the park.

• Elk became less cautious and settled in one place to eat more.

• Elk numbers increased significantly due to the absence of predators.

How do African forest elephants contribute to the biodiversity of their forest ecosystem?

• They primarily eat small plants, allowing larger trees to grow.

• They create new water sources by digging holes in the ground.

• They knock down acacia trees, allowing light for other plants, and spread seeds through their dung.

• They build nests in trees, providing shelter for other animals.

What is the primary role of parrotfish in maintaining healthy coral reefs?

• They build new coral structures.

• They protect coral from predators.

• They eat macroalgae, preventing it from smothering coral.

• They act as a food source for larger reef inhabitants.