Under a White Sky: The Nature of the Future

by Elizabeth Kolbert

The number of species that can be found on a healthy patch of reef is probably greater than can be encountered in a similar amount of space anywhere else on earth, including the Amazon rainforest. Researchers once picked apart a single coral colony and counted more than eight thousand burrowing creatures belonging to more than two hundred species. Using genetic-sequencing techniques, other researchers tallied the number of species they could find of crustaceans alone. In one basketball-sized chunk of coral from the northern end of the Great Barrier Reef, they came up with more than two hundred species—mostly crabs and shrimp—and in a similar-sized chunk from the southern end, they identified almost two hundred and thirty species. It’s estimated that, worldwide, reefs are home to between one and nine million species, though the scientists who conducted the crustacean study concluded that even the high-end estimates probably are too low. It is likely, they wrote, that “the diversity of reefs” has been “seriously under-detected.”