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Environmental Science

The Role of Keystone Species in Trophic Cascade Regulation

Quick fact

In the North Pacific, the presence of sea otters indirectly keeps kelp forests thriving: otters eat sea urchins, which otherwise overgraze kelp. When otters were hunted to near extinction, urchin populations exploded and devastated the kelp, demonstrating how a keystone species controls an entire cascade.

Why this is interesting

You've seen ecosystems, but what if removing just one animal could cause the entire forest to disappear? That's the power of a keystone species.