Coral reefs are also among the most ancient of marine ecosystems, dating back to the Mesozoic era some 225 million years ago. Modern reefs can be as much as 2.5 million years old. This rock forms habitat for an estimated one to nine million species possibly one quarter of all the species in the sea. Reefs are also invaluable as breakwaters that protect shorelines from storm damage and attract tourism. Because of their high biodiversity, coral reefs have supplied many unusual chemical compounds that show promise for treating inflammatory conditions, microbial infections, viral diseases, and some kinds of cancer.
Coral reefs are among the most endangered ecosystems on Earth.
During the first half of 1998, the Tropics experienced a marked increase in sea surface temperature. Beginning in the late 1980s, scientists at EDF and other organizations have warned that increased global warming could result in more widespread and severe coral bleaching. Coral Reef Initiative Task Force meets in Biscayne National Park, Florida to address problems facing the coral reef systems.