9304345 Lockley In this renewal, PI and collaborator A. Hunt will conduct further studies of biostratigraphy, and paleoecology and systematics of vertebrate tracks on the Colorado Plateau, where the record is exceptional. PI will expand, curate and synthesize his data base, going into older strata than most previous work; fossils will be placed in a new repository established by his institution. Work will allow new and better correlations, and assemblage data will also provide insights into the composition, diversity and distribution of communities. ***