Coral Reefs Are Bleaching to Death

Coral reefs are dying faster than we thought, and the reason will shock you.

These underwater cities cover less than 0.2 percent of the ocean but house 30 percent

of all marine life. Think of coral as tiny apartment buildings where millions of sea creatures live,

eat, and raise their families. Here's what's killing them.

Coral has a secret roommate, microscopic algae called zooxanthellae that live inside

their tissue. These algae are like solar panels, making food through photosynthesis and

sharing up to 95 percent of it with the coral. It's the ultimate partnership.

But when ocean temperatures rise just half a degree above normal, this relationship falls apart.