Unusual Vertebrate Microfaunas From the Willwood Formation, Early Eocene of the Bighorn Basin, Wyoming

  • Mary T. Silcox
  • Kenneth D. Rose
Part of the Topics in Geobiology book series (TGBI, volume 18)


The Bighorn Basin of northwestern Wyoming is well known for its extensive and richly fossiliferous Paleocene and Eocene alluvial deposits, which have preserved events in the early Cenozoic history of mammals in unusually fine detail (e.g., Bown and Rose, 1987; Rose, 1990; Bown et al., 1994a, b; Silcox and Rose, 1997; Gingerich, 1989; O’Leary, 1996). Fieldwork in this region dates back to 1880, when Jacob Wortman uncovered the first fossilized mammalian remains (Gingerich, 1980). Since that time, field crews headed by Sinclair, Granger, Jepsen, Gilmore, Simons, Gingerich, and Bown and Rose have built extensive collections of early Tertiary vertebrate fossils. Tens of thousands of jaws and hundreds of skeletons provide a detailed record of the morphology of early mammalian taxa, and of the faunal composition of the region as a whole (e.g., Bown et al., 1994b).


Small Mammal Mammalian Fauna Fossil Mammal Vertebrate Paleontology Surface Collection 
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Copyright information

© Springer Science+Business Media New York 2001

Authors and Affiliations

  • Mary T. Silcox
    • 1
  • Kenneth D. Rose
    • 2
  1. 1.Department of AnthropologyPenn State UniversityUniversity ParkUSA
  2. 2.Department of Cell Biology and AnatomyJohns Hopkins University School of MedicineBaltimoreUSA

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