Silent Sentinels

Coral reefs are the jewels of the ocean. Communities of organisms as rich and diverse as any above or below the surface of the planet, they encircle the tropics like an azure necklace. SILENT SENTINELS reveals disturbing evidence that even if coral can survive continually rising ocean temperatures, they won't be able to escape the chemical effects of high levels of carbon dioxide in the atmosphere. It is the story of a polyp and a plant, one of the most successful biological relationships in the history of Earth and now greatly endangered.