Every Inch of the Seafloor

REEF TOWER SOUTH PACIFIC, 50 MILES EAST OF CAPE YORK PENINSULA, AUSTRALIA Scientists at James Cook University in Australia were charting underwater habitats just beyond the northern end of the Great Barrier Reef using multibeam sonar when they came on a freestanding coral reef tower 1,640 feet tall—taller than the Empire State Building. The base of the wedge, shaped like a shark fin, is almost a mile across, and the tip is only 130 feet below the sea surface. Subsequent dives by a remotely operated vehicle showed the tower was teeming with fish and exhibited no signs of the coral bleaching that has tormented the Great Barrier Reef. Illustrations by Maceij Frolow