Late Glacial environmental changes indicated by a coleopteran succession from North Wales

Abstract

This investigation was designed to compare the environmental inferences that can be made from fossil Coleoptera with those that can be made from palynological data. In the Glanllynnau kettle hole, sedimentation began at 14,000 BP and continued until about 10,000 BP. The Coleoptera from these deposits show that during this period there was only one climatic oscillation and that this differed in both timing and intensity from oscillations inferred from palynological evidence. Thus, at about 13,000 BP, an intensely cold continental climate suddenly gave place to a period with summer temperatures at least as warm as those at the present day, but during this episode the landscape was entirely without trees. From 12,000 BP to about 10,000 BP there was a progressive deterioration in the temperature, and the period of Betula forest, broadly equivalent to the Allerød, is shown to have a less thermophilous fauna than that of the previous pollen Zone I. An attempt is made to explain this anomaly in terms of the differential rate of response of the plants and animals to rapid climatic changes.