An international team of researchers including those at Scripps Institution of Oceanography at the University of California San Diego and the University of Southampton, U.K., unlocked the secrets behind a non-bioluminescent population of plankton off the U.S. West Coast. They found that two chemicals needed for bioluminescence – luciferin and luciferase – are either lacking or not functioning. The study appears in the journal Limnology and Oceanography.