Sea Urchins and Sand Dollars: Echinoidea

In the United States, red, purple, and green sea urchins are harvested for their eggs, which people eat. In Japan, urchin eggs and reproductive organs are eaten as delicacies. In areas where predators of sea urchins have been over-fished, huge numbers of sea urchins damage the environment. In the Caribbean Sea, for example, sea urchins have caused ninety percent of the erosion of coral reefs. Because they are so efficient at consuming unwanted algae and waste, sea urchins are used in aquariums. Sand dollar shells are prized by beachcombers and collectors.