A recent scientific survey on the Galápagos Archipelago has added ten corals to the list, including the Floreana coral (above).

In the 1980s, frequent El Niño weather patterns—which made ocean temperatures fluctuate—likely led to the poor state of the Galápagos corals.

Some scientists worry that global warming may make El Niño events more regular and prevent corals from recovering.

Until recently, scientists had not properly assessed the health of the world's tropical corals. Scientists estimate that human activities—such as pollution, global warming, and sedimentation—could kill 30 percent of reefs in the next three decades.

Coral reefs in the Indian and Pacific Ocean, for example, are vanishing faster than rain forests.

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