In one frame International Space Station astronauts were able to capture the evolution of fringing reefs to atolls. As with the Hawaiian Islands, these volcanic hot spot islands become progressively older to the northwest. As these islands move away from their magma sources they erode and subside. The two large islands, Raiatea and Tahaa, share a single fringing reef. The next island to the northwest, Bora-Bora, consists of a highly eroded volcanic remnant with fringing reef. The last island, Tupai, signifies the destiny of these islands; the fringing reef has become an atoll with the central island below sea level.
More information and photographs of tropical islands is included in the Islands chapter of Oceanography from the Space Shuttle (Links to this were removed because they no longer work).