Farzaneh Mansouri’s future data collectors are cruising around oceans worldwide, following blooms of productivity and accumulating decades of information—all in their earwax. Mansouri, an environmental scientist at Baylor University in Waco, Texas, studies the wax “earplugs” built up over years in sealed whale ear canals. The earplugs, according to her findings, provide records of the animals’ movements and diets over the course of their long lives.