DefenseFun fact: The red spotted coral crab may be small, but animals should think twice before messing with it! It lives on and in coral, and will defend its home, using its claws to pinch and drive away predators who want to eat it or its coral. For example, when a crown-of-thorns sea star climbs on top of its coral, it will pinch at its tube feet. The pain forces the sea star to crawl away, defeated. Since the coral provides the crab with a safe place to live, and the crab protects it from predators, they live in a close, or symbiotic, relationship that is mutualistic—good for both of them.
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Reef Creature Identification Tropical Pacific by Paul Humann and Ned Deloach.