Master of Science (MS), Bowling Green State University, 2018, Geology

Sauropods have been one of the most studied dinosaur groups due to their extremely large body size. An open question is what these animals ate to reach such gargantuan sizes. The diets of fossil vertebrates can be determined by examination of microscopic wear patterns on the surface of the teeth, which can distinguish between hard and soft foods and constrain the feeding height and food selectivity of the animal. This study examined the microwear patterns on ten Late Jurassic sauropod teeth from the Morrison Formation of North America, including the diplodocids Barosaurus, Diplodocus, and Suuwassea and the macronarian Camarasaurus, using scanning electron microscopy (SEM). In addition, the capability of a three-dimensional laser scanner, a less expensive and potentially less damaging method than SEM, to image these microwear patterns was tested. The SEM images were analyzed for wear patterns, before they were marked on the images and the lengths and widths of the wear was measured. The 3D images were also examined to test if microscopic wear could be seen on the models. The 3D scans proved too coarse to view microscopic detail while only scratches were found on six of the ten teeth tested. No wear was found on the Barosaurus teeth tested. From this information it was concluded that both Suuwassea and Camarasaurus fit with previous studies indicating both were more selective, mid-height browsers while the single Diplodocus tooth tested did not match the previous study which indicated the animal should be a low level non-selective browser due to the lack of pitting visible on the wear surface. The laser scanner proved unable to create images fine enough to see the microscopic wear on the teeth, which indicates that while still a valuable tool in other circumstances, the 3D scanner has not reached a point where it can completely replace the older SEM method.

Committee: Dr. Margaret Yacobucci Dr. (Advisor); Dr. John Farver Dr. (Committee Member); Dr. Yuning Fu Dr. (Committee Member) Subjects: Biology; Geology; Paleontology