Abstract: Ecologists typically presume that competition for resources harms individuals through direct effects on their vital rates. However, recent theoretical work suggests that some systems are governed by a different mechanism: competition for time. Competition for time occurs when species reduce the amount of time their competitors grow for, rather than their competitors' growth rates. In my talk I will first introduce this novel framework and explain how it arises from careful consideration of plant ecophysiology under resource limitation. Then, I will describe how this mechanism promotes coexistence among species of plants both in theory, and using data from an experiment conducted in an annual grassland in southern California, U.S.A. Finally, I will apply this framework to make predictions about how changing precipitation patterns over the next century will impact plant biodiversity. Specifically, I will detail my finding that increases in the magnitude of precipitation events will benefit biodiversity, while increases in the frequency of precipitation events will erode it.
