Life on earth is fundamentally shaped by variability. Yet ecologists are only just beginning to understand the essential role that fluctuating, heterogenous conditions play in driving major biological patterns. Species’ differing responses to variation potentially become one of the most important drivers of biodiversity patterns, and these responses reflect myriad adaptations to anticipate variation in the environment. In this session, we explore recent discoveries about the ways that differing organismal responses to variable environments drive population dynamics and patterns of community diversity. We highlight an emerging dimension of this work which explores how ecological information used by organisms — i.e. patterns in their environment that are predictable enough to serve as cues for finding resources, mates, or refuges — influences population and community dynamics. By using information, organisms stand a better chance of tracking beneficial conditions and avoiding detrimental ones. Information is present in cues when they correspond to patterns of environmental variation, and information is useful when it is predictive of conditions that promote or inhibit species’ growth or reproduction, and when that information is detectable to the organisms. The results presented in this session demonstrate the potential to generate novel hypotheses about the drivers of biodiversity when species’ responses to variable environments are treated as a fundamental feature of natural systems. In particular, our session is intended to improve ecologists’ understanding of environmental variation’s role in ecological dynamics by establishing a conceptual foundation based on well-tested mathematical techniques and drawing explicit links between ecological studies on species’ responses to varying environments. It is our hope that this symposium can draw together scientists from diverse ecological backgrounds with the united interest of understanding how species’ responses to environmental variability — both passively and actively through the use of information — act as major drivers of ecological dynamics.