It was 2 o’clock in the morning, and marine scientist Felicia Coleman, floating 150 kilometers offshore of the gulf coast of Tampa, Fla., was growing weary of looking at a monitor. It was displaying live images being captured by the remotely operated vehicle (ROV) some 90 meters below, showing lots of rock clusters inside holes in the seafloor, but nothing to explain how the holes got there. Then Coleman saw something unexpected—red grouper sweeping rocks from the seafloor holes they call home with their tail fins.
“It was one of those moments [that] you see these cartoons where scientists are yelling, ‘Eureka! I’ve found it!’” recalls Coleman, based at Florida State University. “It woke us up.” Watching the video stream, the researchers started to get the sense that the grouper were actively digging the holes, creating this habitat for themselves and the other fish. They had gone out to see ...
