coral reef coral reef

Much of the inner reef at Oahu's Hanauma Bay is dead after decades of tourism. The state may sign a law banning over-the-counter sunscreens believed to harm coral. Caleb Jones/AP hide caption

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Caleb Jones/AP

A 2014 photo shows coral on Australia's Great Barrier Reef. The Australian government is dedicating hundreds of millions of dollars to protecting and researching the reef. William West/AFP/Getty Images hide caption

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William West/AFP/Getty Images