Biodiversity studies of past and modern communities are key to understand the long-term patterns and processes related to ecosystem change in which repositories and historical/legacy data are important. Although the Quaternary fossils are better represented in global databases like Paleobiology Database or Global Biodiversity Information Facility, unfortunately, most of these data come from the well-studied parts of the world, e.g., the USA and Europe, while Indian data are sparse. It is therefore of utmost importance to focus on the Indian diversity data repositories, even for the Quaternary. Furthermore, historical data from field reports, field notes, and core registers can be important sources of legacy data. This session, in this context, welcomes contributions on how legacy data and repositories can aid in understanding varied research questions related to diversity, paleoecology, paleoenvironment, and paleoclimate, with special emphasis on Indian Quaternary data.