coral

These images show the dire threat to the world's reefs, which hold some 25 percent of marine life.
Ryan Duffy explores in the latest episode of "Now What"
Just one drop of the stuff can damage delicate corals.
You may never see them, but coral reefs are suffering along with the rest of our planet.
The robot's target is a species of coral-eating starfish responsible for extensive reef damage.
"I’d be very surprised if we didn’t see many animals and phenomena that are new to science."