AN 11400 YEAR PALEOECOLOGICAL HISTORY OF A BRITISH CHALK GRASSLAND

The first broad-based, paleoecological analysis of a Sedimentary sequence on the British chalk, dating to the terminal Pleistocene, reveals a history of climatic, vegetational and faunal change. The past co-occurrence of currently allopatric species among molluscs, beetles and plants supports hypotheses of the impermanence of communities. Modern pollen rain data are utilized to refine the ecological interpretation of the fossil pollen data. The presence of the Windermere Interstadial (Allerod) and the Loch Lomond re-advance (Younger Dryas) are represented by decreased abundances of arboreal taxa and increased representation of cold grassland elements. Open grassland habitats appear to have been a continuous landscape element, at least locally. since the late-glacial period on the northern British chalklands, although their species composition has changed greatly in the last 11 400 yr.