Date of Award


Degree Name

Master of Arts



First Advisor

Dr. Bob Anemone

Second Advisor

Dr. Chris Beard

Access Setting

Masters Thesis-Open Access


A new early Eocene mammalian fauna from a series of localities in the Great Divide Basin of southwestern Wyoming is described in this Masters Thesis. Seven localities in the vicinity of Tipton Buttes have yielded 1627 fossil specimens that have been identified, catalogued, and analyzed. The goal of this thesis is to develop a biostratigraphic framework for dating this fossil assemblage based on comparisons with well-dated assemblages from other localities in the American West. Field crews from Western Michigan University have collected fossil vertebrates from Tipton Buttes during most summer field seasons between 1995 and 2003. The analyses indicate that the fossils from Tipton Buttes most likely date from the Lysitean (Wa6) subage of the Wasatchian North American Land Mammal Age. This identification is based on the presence of representative mammalian taxa from the Lysitean including the apapid primate Cantius abditus, the hyopsodontid condylarth Hyopsodus minor, and the absence of younger forms like Lambdotherium.

Included in

Anthropology Commons