Many ecological processes operate at timescales beyond those of direct human observation. Even multi-year modern ecological analyses cannot encompass the full range of past environmental conditions, much less those envisioned in the near future. Thus, predicting future biotic responses to environmental change and establishing pre-human baselines for conservation and remediation efforts necessitates incorporating historical and paleontological data. The past decade has witnessed increased emphasis on long-term ecological studies because of the deepening understanding that biotic systems are inherently dynamic and that longer temporal scales are critical to understanding the role of natural variability. Paleoecologists have also made significant advances in recent years, quantifying the ecological fidelity and temporal acuity of the fossil record, and developing a suite of independent environmental proxies that extend the temporal depth of direct empirical data back through the Quaternary. While both neontological and paleontological communities recognize the urgent need for establishing target baselines for restoration efforts, opportunities for interaction between the two communities have been limited, hindering the development of critically important collaborative research efforts. In bringing these communities together, this session will present innovative and multidisciplinary tools for (1) establishing the natural range of environmental variability and ecosystem function, (2) analyzing past ecosystem response to climatically driven environmental change, and (3) understanding how ecosystems are responding now to progressive human impacts. Speakers work at a variety of temporal scales and across disparate taxonomic groups, using innovative approaches to document faunal change over time. In addition, this session will provide an overview of the quality of data recorded in geohistorical archives, and stress the development of robust analytical techniques for applying geohistorical data to modern-day conservation and remediation issues.