The Red Moss deposits rest in a hollow which began to collect organic sediments I2,ooo years ago. The sediments, moss peat, sandy organic mud and Phragmites peat, yielded abundant wellpreserved insect remains. The species are all living today but many no longer in the British Isles. The fauna of the Late-glacial environment is one of an open and exposed bog but by Post-glacial time this had been superseded by a fauna of shrub and tree-covered wetland. Other changes in faunal composition have been observed which are thought to have been caused by oscillating thermal conditions. A series of colder and warmer episodes has been postulated which may be broadly correlated to the palynologically inferred climatic history of the Late-glacial. A marked faunal change was observed between the Late- and Post-glacial episodes and it is estimated that summer temperatures rose from IO° C to I6° C in a period of 3o to 45o years based on radiocarbon dating. Faunal changes are independent of lithological boundaries, which, because of the largely organic nature of the sediments, are vegetation controlled and this is thought to demonstrate the more positive response of insects to climatic change.