By controlling the spread of vegetation and the balance of certain fish species, the American alligator serves as a(n) in its ecosystem.

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Explanation:

Alligators play an important role in maintaining ecosystem balance. Sitting at the top of the food chain, alligators are top predators and help keep other animal populations in balance. By digging holes and leaving trails throughout marshes, they create habitats for fish and marine invertebrates

. the sierra madre fault zone of southern california

. the san andreas fault california