Nancy Knowlton

Sant Chair in Marine Science. Knowlton made major contributions to the fields of genetics, evolution, ecology, and the behavior of reef-building corals and their associated organisms. Tropical reefs shelter up to one third of all marine species, many of which are in danger of extinction. From bases at the National Museum of Natural History, the Scripps Institution of Oceanography, and the Smithsonian Tropical Research Institute, her research on the coral Montastraea annularis transformed understanding about genetic diversity and species richness in reef-building corals and their associated symbiotic algae. She demonstrated that what had long been considered a single species of coral was actually three, and that the different algae hosted by these corals are differently sensitive to high temperatures --important because this coral is widely studied by biologists and geologists as a model system, and because of the sensitivity of corals to global warming. She also showed that corals host a staggering array of bacteria, providing a foundation for understanding their vulerablity to diseases.