Resolution of the causes and extent of faunal turnover in the past has been complicated by the absence of fossil beds that document such changes over fine time scales. This proposed work will examine temporal change in taxonomic diversification of tetrapods in Late Triassic and Early Jurassic strata of the Newark Supergroup of eastern North America at 20,000-year intervals. By examining three temporally equivalent sets of beds whose fossils occupied different habitats, the principal investigator will document diversification at relatively fine levels and test whether declines of potentially competing non- dinosaurian clades were required for expansion of dinosaur groups. The entire study is intended to provide a basis for global comparisons.
