RIVERO VEGA, Rafael A., Museum of Paleontology, University of Michigan, Ann Arbor, MI 48109; Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109, CLARKE, John T., Institute of Ecology and Earth Sciences, Department of Zoology, University of Tartu, Tartu, 50090, Estonia; Department of Ecology and Biogeography, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Toruń, 87-100, Poland and FRIEDMAN, Matt, Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109; Museum of Paleontology, University of Michigan, Ann Arbor, MI 48109