Predicting the evolution of adaptation and plasticity from temporal environmental change

Abstract

Environmental change drives evolutionary adaptation, which determines geographic patterns of biodiversity. At a time of rapid environmental change, however, our ability to predict its evolutionary impacts is far from complete. Temporal environmental change, in particular, often involves joint changes in major components such as mean, trend, cyclic change, and noise. While theoretical predictions exist for adaptation to temporal change in isolated components, knowledge gaps remain. To identify those gaps, we review the relevant theoretical literature, finding that studies rarely assess the relative effects of components changing simultaneously, or attempt to translate theoretical predictions to field conditions. To address those gaps, we draw on classic evolutionary theory to develop a model for the evolution of environmental tolerance, determined by an evolving phenotypically plastic trait, in response to major components of temporal environmental change. We assess the effects of different components on the evolution of tolerance, including rates of adaptation towards new environmental optima, and the evolution of plasticity. We retrieve and synthesize earlier predictions of responses to components changing in isolation, while also generating new predictions of responses to components changing simultaneously. Notably, we show how different forms of environmental predictability emerging from the interplay of cyclic change, stochastic change (noise), and generation time shape predicted outcomes. We then parameterise our model using temperature time series from global marine hotspot in southern Australia, illustrating its utility for predicting testable geographic patterns in evolved thermal tolerance. Our framework provides new insights into the evolution of adaptation and plasticity under temporal environmental change, while offering a path to improving predictions of biological responses to climate change.