Extreme Variation in the Sagittal Crest of Tapirus polkensis (Mammalia Perissodactyla) at the Gray Fossil Site Northeastern TN.

• Main Author: Abernethy, Aaron Randall
• Format: Others
• Published: Digital Commons @ East Tennessee State University 2011
• Subjects: Sexual Dimorphism; Ontogeny; Morphology; Miocene; Earth Sciences; Paleobiology; Paleontology; Physical Sciences and Mathematics
• Online Access: https://dc.etsu.edu/etd/1348; https://dc.etsu.edu/cgi/viewcontent.cgi?article=2539&context=etd

The preservation and quantity of fossil tapirs (Tapirus polkensis) from the Gray Fossil Site in northeastern Tennessee provides a unique opportunity for comparison and analysis of skeletal characters. Intraspecifically, modern tapirs show little to no variation in the morphology of the sagittal crest. However, several different morphologies exist within the sample at Gray. No osteological evidence of sexual dimorphism exists for tapirs, and no correlation between crest shape and sex was observed. Several juveniles display well defined crests, while some adults have only minor thickening of the temporal ridges; therefore, no distinct correlation between age and crest state could be established. Three different patterns of wear exist within the sample, but there is no correlation between these and crest morphology. No cranial pathologies were found to be associated with a crest type. Despite some correlations the sagittal crest could simply be a variable character due to intraspecific variation.