Landmark Analysis of Musteloid Carnassials Applied to Taxonomic Identification and Examination of Sexual Dimorphism and Regional Morphotypes

Guy Wilson Cave (GWC) in Sullivan County, Tennessee holds many late Pleistocene mammal fossils. Based on visual morphology, several partial mandibles with lower carnassial from GWC appeared to be musteloids. Geometric morphometrics has been successfully used to identify fragmentary fossils, so a landmark based, 2 dimensional technique was applied to identify the GWC musteloids using the lower carnassial. Digital images of several GWC fossils and of extant reference musteloids were combined using morphometric programs tpsDIG1, tpsUtil, and tpsSuper. Statistical data analysis was performed in PASW Statistics. Results successfully separated Mephitis mephitis (striped skunk) from M. macroura (hooded skunk) and Martes americana (American marten) from M. pennanti (fisher). Sex-based and geographical patterns were also found in the data. Sex separated all three species via the lower carnassial. Geographic divisions were found for Mephitis mephitis, Martes americana and M. pennanti populations that hint at interestingly unique biogeographical histories for each taxon.