Sharks are infamous meat-eaters. The ocean’s buffet of fish, crabs, mussels, shrimp and krill fill the legendary predators’ stomachs and give them sustenance. Now researchers have discovered that one particular species, bonnethead sharks, also dine on seagrass to meet their nutritional needs. The discovery means bonnethead sharks are not carnivores but omnivores — a distinction that changes how the coastal swimmers influence the fragile ecosystems they call home.