A method for reconstructing climate from fossil beetle assemblages

Fossil beetle remains have been used to reconstruct temperatures. One method by which these reconstructions are made-the Mutual Climatic Range method-is based on the overlap of the observed modern climatic ranges of the beetles present in a fossil sample. A limitation of this method is that it does not exploit variations in the rate of occurrence of a species within its climatic range. We present an alternative method that uses observed variations in this rate in modern data for climate reconstruction. The method is shown to perform well in an experiment using modern data from North America.