Corals Find an Effective Way to Spawn Despite Being Cemented in Place

It is hard to court the opposite sex when you are cemented in place, which explains why polyps–the tiny creatures whose exoskeletons form corals–do not reproduce by mating. Instead they cast millions of sperm and eggs into the sea, where they drift up to the ocean surface, collide, form larvae and float away to form new coral reefs

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Corals Find an Effective Way to Spawn Despite Being Cemented in Place