A statistical approach to temporal biostratigraphy

Abstract

Various statistics (similarity coefficients) can be constructed for faunal assemblages which vary more or less regularly as these assemblages change. Methods are described for placing assemblages on an evolutionary scale, the units of which are equal amounts of evolutionary transformation in the species makeup of assemblages. The greatest single factor involved in the scaling appears to be time; the effects of zoogeography are also discussed. Characteristics of different similarity coefficients differ, and some of these characteristics are discussed. Applying our method to faunal assemblages from East African hominid sites, reasonable correlations can be established between Olduvai Gorge, Tanzania, the Shungura Formation, Ethiopia, and the Koobi Fora Formation, Kenya.