Nutrient storage links past thermal exposure to current performance in phytoplankton

Environmental temperatures impact the majority of ecologically significant processes that ultimately shape the Earth’s biodiversity and ecosystems. Temperature changes affect the growth of organisms quickly by constraining rates of resource acquisition and utilization, and gradually by altering the organisms’ phenotype. To understand and predict how temporal variability in temperature affects population dynamics and persistence, we need general, mechanistic theory that captures both of these temperature effects. Here, we show that internal nutrient storage explains the effects of thermal experience on phytoplankton growth. Because the fundamental processes of resource acquisition, storage, and assimilation are shared by all life, phenotypic memory produced by temperature-dependent resource storage likely affects the performance of a wide range of organisms.