Many people think pocillopora coral are plants, but they’re actually animals! Each mass of coral that you see is actually hundreds of tiny animals living together. Each tiny animal is called a polyp, and hundreds of coral polyps living together are called a colony.

Like jellyfish and anemones, corals are cnidarians, which means they have a sac-like body with a mouth and tentacles on top. What makes corals different from other cnidarians is that they make their own skeletons and wear them on the outside of their body, like armor. By adding to their armor every year, they grow bigger and bigger, but they only live in the top most layer of their skeleton. The parts underneath are old skeleton bits that make up the reef.