Penny Chisholm

Sallie Watson "Penny" Chisholm is an American biological oceanographer at the Massachusetts Institute of Technology. She is an expert in the ecology and evolution of ocean microbes. Her research focuses particularly on the most abundant marine phytoplankton, Prochlorococcus, that she discovered in the 1980s with Rob Olson and other collaborators. She has a TED talk about their discovery and importance called "The tiny creature that secretly powers the planet".