Establishing viviparid gastropods as Cenozoic continental environmental archive; with case studies on Oligocene SE-Asian initial icehouse weather, on climate variability during the Plio-Pleistocene transition in Central Asia, and on genetic and environmen

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Cenozoic palaeo-environmental continental archives which can be used to infer high-resolution, multi-annual to intra-seasonal climate and weather signals are scarce, with some exception of Late Holocene dendroclimatological avenues. Viviparid gastropods have been identified by us to have a high potential to study past environments. Species inhabit fluvial and lacustrine systems of all continents except for South America and Antarctica. Since the Eocene the group has diversified strongly. Although most Cenozoic shells, particularly of the subfamily Bellamyinae, are characteristic, including features such as keels, ribs and spines, taxonomical and thus ecological assignment is often difficult, especially due to the lack of early ontogenetic shell data and unambiguous morphotype analyses considering (palaeo-) environmental settings. Thus early ontogenetic shells will be SEM-documented in detail and late ontogenetic shells will be studied by 3D-fractal-geometry. The influence of the environment on shell sculpture will be tested using a physicochemical-morphometric approach. A special focus (case study) will be put on relating shell plasticity with gene expression. Viviparid gastropods are comparatively large and thus allow sclerochronological sub-sampling for stable isotope studies in a resolution of a week or even less. Two further case studies will address palaeo-weather patterns: a) Oligocene initial (monsoonal?) icehouse climate and weather conditions in Southeast Asia and b) changing climate and weather patterns and faunal shifts during the Plio-Pleistocene icehouse to ice age transition in Central Asia.