The Present and the Past: The Interpretation of Sub-FossilMolluscan Assemblages and the Relevance of ModernStudies, with Specific Reference to Wet-Ground Contexts inthe UK

The interpretation of sub-fossil Mollusca from archaeological contexts and Holocene soils and sediments has always relied upon there being a relationship between the present and the past. It is possible to reconstruct past environments and landscapes, since virtually all of the species found as Holocene subfossils are still to be found in the British Isles. A standard uniformitarianist approach can readily be adopted, where the modern ecologies (or aspects of the modern ecologies) of species (or groups of species) can be applied back through time. While this is not without its difficulties, many of which are outlined below, Thomas (1985, 149) correctly noted that sub-fossil analysis has worked ‘because the data generally make ecological sense’. This paper will consider some of the general theoretical difficulties of a uniformitarian approach to the interpretation of sub-fossil Mollusca, in particular concentrating on the issues surrounding the theoretical problem of non-analogue communities (Gee and Giller 1991). Attention will then turn to wetlands, with a discussion of assemblages recovered from Holocene overbank alluvial deposits and modern floodplain faunas, although the implications of the demonstrated relationships between present and past are wider. This will be followed by discussion of the interpretation of sub-fossil molluscan assemblages recovered from early-mid Holocene tufa deposits, and how modern ecological work might help improve the level at which we can reconstruct the environments in which such deposits formed.