Seaweed-Threatened Corals Send Chemical SOS to Fish
When a killer seaweed touches a kind of spiky coral, the coral pushes a chemical panic button that brings small resident fish to the rescue. Unchecked, seaweed algae can overrun a coral reef, as the community dwindles in “a descent into slime,†says marine ecologist Mark Hay of the Georgia Institute of Technology in Atlanta. But within 15 minutes of contact with a toxin-making seaweed, an Acropora nasuta coral releases compounds that prompt goby fish to seek out and trim back the seaweed, Hay and colleague Danielle Dixson report in the journal Science.