When Socrates said, “He is richest who is content with the least,” he was referring to human affairs, but he could just as well have been talking about tiny ocean organisms the Greeks called phytoplankton. According to a recent study in Proceedings of the National Academy of Sciences co-authored by Adam Martiny, associate professor of Earth system science and ecology at UCI, marine phytoplankton are frugal with nutrients when they’re in short supply. Plankton need elements such as phosphorus and nitrogen for growth and basic biological functions. Martiny and co-author Eric D. Galbraith of McGill University show that frugal phytoplankton may obtain more CO2 in warm, nutrient-depleted parts of the ocean than previously thought. By doing so, they can have a significant impact on marine ecosystems and the level of atmospheric carbon dioxide. “The role frugal phytoplankton play is potentially very important for the global carbon cycle but currently ignored in climate models,” said Martiny, who also directs the UCI OCEANS initiative.