Degree Name

MS (Master of Science)



Date of Award


Committee Chair or Co-Chairs

Blaine W. Schubert

Committee Members

Joshua X. Samuels, Chris Widga


North American black bears and brown bears can be difficult to distinguish in the fossil record due to similar dental and skeletal morphologies. Challenges identifying ursid material from Oregon Caves National Monument (ORCA) called for an accurate tool to distinguish the species. This study utilized a large database of lower tooth lengths and ratios in an attempt to differentiate black and brown bears in North America. Further, this project examined how these linear measurements differ geographically. Analysis of variance (ANOVA) found significant differences between black and brown bears from across North America for every variable studied. Stepwise discriminant analyses (DA) found lengths separated species better than ratios. When sexes were analyzed, ANOVA only found significant differences for lengths while DA found lengths and ratios could not accurately distinguish between sexes. Fossil specimens from North America, including ORCA specimens, demonstrated the utility of this study, supporting several identifications and questioning others.

Document Type

Thesis - unrestricted


Copyright by the authors.