Coral reefs are the most diverse of all marine ecosystems. They teem with life, with perhaps one quarter of all ocean species depending on reefs for food and shelter. This is a remarkable statistic when you consider that reefs cover just a tiny fraction (less than one percent) of the earth’s surface and less than two percent of the ocean bottom. Because they are so diverse, coral reefs are often called the rainforests of the sea. ( More here )
Thanks to Lucie Thomas for forwarding video.