Meeting Summary: A central challenge in understanding the origins of biodiversity is that, while we can observe and test local ecological phenomena, we must usually infer the longer-term outcomes of these ecological forces indirectly. We propose to develop inferential models at the interface between macroecology and population-level processes, and apply them to data from geological or ecological chronosequences that present communities of different ages. Inferences from these "snapshots in time" thereby allow for model validation and a link between direct observational methods for local communities and models that make indirect inferences underlying community history. We propose to directly link ecological theories and models of community composition and comparative population genomics, all within a temporal framework. Our approach is to use approaches from statistical mechanics to understand the long-term steady state dynamics of biodiversity, and then build a unified model bridging theory from phylogenetic and comparative population genomics with ecological processes to understand the non-steady state history underlying patterns of species diversity. This model will then be used to make joint predictions of species abundances and genetic diversities over time. We will then test this model with data collected across diverse taxa and a range of systems that provide snapshots in time. This unified approach will bridge ecological and evolutionary theory to elucidate processes responsible for origins and maintenance of species diversity and provide a framework for making predictions about future biodiversity dynamics.