Understanding the mechanisms responsible for the generation of biodiversity and its maintenance is critical in developing effective strategies for conservation and ecological restoration. Geohistorical records allow ecologists to test for the generality of processes responsible for the maintenance of biodiversity over a range of natural environmental variation. Further, such records provide necessary baselines, prior to the onset of anthropogenic influences, with which to compare recent ecological patterns and processes. However, widespread misconceptions exist regarding the quality of geohistorical records and their application to ecological questions. Paleobiology has made great strides in understanding and accounting for biases in the fossil record, opening new avenues for application of modern ecological theory, in a scale-informed context, to paleoecological and evolutionary problems. This symposium will first present a synopsis of the ecological fidelity and acuity of geohistorical records in both marine and terrestrial settings. Building upon this foundation, speakers will address paleoecological research at multiple levels of organization from community to global scale biodiversity dynamics, focusing on the following two themes: 1) community restructuring in response to past environmental shifts, and 2) factors influencing extinction risk at community and macroecological scales. The research presented will apply theory and methods from diverse areas of ecology including niche theory, food web dynamics and metabolic scaling to provide insights into the ecological processes structuring biodiversity over longer temporal scales from the near to distant past.