This project -- the final two years of a five-year endeavor -- involves the collecting, preparation and study of outstanding remains of extinct vertebrates from the eastern Wind T+River Basin, Wyoming. Specifically, the project involves: (1) the excavation of extremely reich fossil quarries that produce unparalleled skulls, skeletons, and dentitions (50 million years old) of the earliest forerunners of many groups os rhinoceroses, even-toed ungulates, bats, marsupials and rodents: (2) survey of adjacent badland rocks (60 million to 35 million years old) to recover additional fossil vertebrates from a longer temporal sequence and broader paleoecological settings in order to reconstruct ancient ecosystems and biodiversity; and (3) the and relationships of these ancient animals. Analysis of the paleobiological problems. Accomplishments of this project to date include: (1) discovery and 60% excavation of extremely rich quarries preserving skulls and skeletons of many Eocene mammals and lizards hitherto known only from teeth and jaws; (2) scientific descriptions and analyses of the material representing ancient marsupials, primates, armadillo-like beasts, rodents, archaic ungulates, and even-toed ungulates: (3) analyses of new, remarkable specimens, e.g.: first known skulls of tarsier-like Shoshonius has overturned traditional views on the primate evolutionary tree; skulls of the lemur-like Notharctus venticolus demonstrate the oldest record of primate sexual dimorphism and imply early primate social behaviors; skull of new rodent, Armintomys, reveals earliest appearance of a specialized jaw structure called hystricomorphy, a major evolutionary innovation in rodents; (4) more precise geology and stratigraphic correlation of Eocene faunas and horizons n the Western Interior of the Rocky Mountains using conventional geologic techniques, and satellite/aircraft remote sensing imagery; (5) analysis of biodiversity and faunal change through time; and (6) detailed studies of evolutionary patterns processes through time. Since 1988, these accomplishments have been documented in 23 papers in professional journals, student dissertations and theses, and presentations at professional meetings.
