GSA Annual Meeting in Indianapolis, Indiana, USA - 2018

Paper No. 122-8
Presentation Time: 3:15 PM


RESIDE, Anna, Department of Earth and Environmental Sciences, Vanderbilt University, 5726 Stevenson Science Center, Nashville, TN 37235; Department of Forestry and Environmental Studies, Yale University, New Haven, CT 06520 and DESANTIS, Larisa R.G., Department of Earth and Environmental Sciences, Vanderbilt University, Nashville, TN 37235

Dental microwear texture analysis (DMTA) is commonly used to assess the dietary ecology of both extant and extinct taxa by examining the patterns of microscopic textures on the occlusal surfaces of teeth. However, different teeth often vary in function and therefore record diet differently. In felids, for example, lower carnassial first molars are most commonly analyzed as these teeth process both flesh and bones, while in ursids and canids which have cusps and teeth posterior to the carnassial sheering facet, the second molar grinding facet is most representative of diet—including carcass utilization. Limiting which tooth facets are examined for dietary interpretations therefore limits which fossils can be included in particular studies, and these limitations are particularly striking for carnivorous mammals because of the relative scarcity of predator species on the landscape. However, the Tasmanian devil (Sarcophilus harrisii), an apex predator, has multiple carnassial-like molars that likely function in similar ways and may record diet similarly. To aid in assessments of the fossil record, it is critical to understand if the dental microwear textures of different teeth in S. harrisii are similar (due to similar function) or different (due to differences in position relative to the mandibular condyle). Here, we compared the complexity (Asfc), anisotropy (epLsar), and textural fill volume (Tfv) of the second, third, and fourth molars of extant specimens of S. harrisii to assess dental microwear texture variability across the tooth row. No significant differences were found between tooth positions, suggesting that lower second through fourth molars share similar functions and capture dietary behavior similarly. Collectively, these data provide critical support that teeth with similar morphologies yield similar functions as evinced by dental microwear textural attributes and the analysis of different teeth with similar forms can be analyzed together to infer the ecology of taxa such as Tasmanian devils.