Courtesy of Seabird McKeon
When scientists removed the largest species of the guard-crabs, Trapezia flavopunctata, from the path of an army of predator sea stars, the effects were dramatic; corals without guard-crabs, or with other species of guard-crab, were eaten—usually overnight. In September 2014, Smithsonian scientists Seabird McKeon and Jenna Moore published new research highlighting the role of diversity in the healthy functioning of coral reef ecosystems, showing that guard-crab species and size classes offer different kinds of effective protection against various threats to coral reefs. (Photo courtesy of Seabird McKeon)
