A Rocky Shoreline That Is Covered at High Tide but Exposed

question 41

Multiple Choice

A rocky shoreline that is covered at high tide but exposed at low tide supports a community of mussels,algae,barnacles,and starfish.An ecologist systematically removes species from different areas of the beach.Removing the mussels or the barnacles doesn't substantially change the community,but removing the starfish dramatically changes the mix of species in the area.Which is the keystone species?

• A) mussels
• B) barnacles
• C) algae
• D) starfish
• E) All of the answers are correct.

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