Cnidarians are soft-bodied, carnivorous animals that have stinging tentacles arranged in circles around their mouths. They are the simplest animals to have body symmetry and specialized tissues. Cnidarians typically have a life cycle that includes two different-looking stages: a polyp and a medusa.
Cnidarians include jellyfishes, hydras and their relatives, and sea anemones and corals.
Ecology of Corals: The worldwide distribution of corals is determined by a few variables: temperature, water depth, and light intensity. Light is necessary because these corals rely on mutualistic relationships with algae that capture solar energy, recycle nutrients, and help corals lay down their calcium carbonate skeletons.
Cnidarians include jellyfishes, hydras and their relatives, and sea anemones and corals.
Ecology of Corals: The worldwide distribution of corals is determined by a few variables: temperature, water depth, and light intensity. Light is necessary because these corals rely on mutualistic relationships with algae that capture solar energy, recycle nutrients, and help corals lay down their calcium carbonate skeletons.