Taphonomic Interpretation of Gnat-Out-of-Hell, an Early Uintan Small Mammal Locality in the Uinta Formation, Utah

Abstract

Fossil mammals from the Uinta Formation of northeastern Utah play a central role in our understanding of the Uintan “North American Land Mammal Age” (Scott and Osborn, 1890; Black and Dawson, 1966; Walsh, 1996; Rasmussen et al., 1999). However, the mammal collections from the Uinta Formation are notably short on small mammals. Historically, most of the work on the Uinta Formation mammals, and consequently our understanding of mammalian evolution in the Rocky Mountain region during the Uintan, has been based on mammals from about the size of Leptotomus (a large ischyromyid rodent), Leptotragulus (a selenodont artiodactyl), and Epihippus (a horse), on up to brontotheres and amynodontid rhinos. Smaller taxa, such as marsupials, insectivores, apatemyids, primates, and the smaller rodents, have rarely been recovered from the Uinta Formation.KeywordsSmall MammalMiddle EoceneLate EoceneFossil AssemblageExtant TaxonThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.