A conceptual framework for understanding thermal constraints on ectotherm activity with implications for predicting responses to global change

Activity budgets influence the expression of life history traits as well as population dynamics. For ectotherms, a major constraint on activity is environmental temperature. Nonetheless, we currently lack a comprehensive conceptual framework for understanding thermal constraints on activity, which hinders our ability to rigorously apply activity data to answer ecological and evolutionary questions. Here, we integrate multiple aspects of temperature-dependent activity into a single unified framework that has general applicability. We also provide examples of the implementation of this framework to address fundamental questions in ecology relating to climate change vulnerability and species' distributions using empirical data from a tropical lizard.