The paleoecology of Guy Wilson Cave is based on 1) systematic identification of cervid material, 2) taphonomic analysis of cervids with a focus on carnivore utilization, and 3) carbon isotopes from cervid and herbivore tooth enamel (δ13C). Systematic identification reveals that there are at least three cervid species in the cave fauna based on fossil remains: Odocoileus virginianus, Rangifer tarandus, and either Cervalces scotti or Alces alces. Separation of Cervalces and Alces based on the dental material was not possible. Taphonomic analysis of gnawing and tooth markings showed alterations by a canid predator, and the overall pattern suggests full-heavy utilization and possible scavenging activity by the dire wolf, Canis dirus. δ13C analysis of the herbivore community showed that taxa were feeding in a dominantly C3 environment, likely a relatively dense forest. Odocoileus showed no dietary shift from the late Pleistocene to today, also suggesting a forested environment in the past.

Cryptobranchus guildayi is described as an extinct species of large salamander that is closely related to the hellbender, Cryptobranchus alleganiensis. The validity of this extinct taxon has been questioned, so an expanded osteological sample of modern hellbenders was used for comparative purposes with the C. guildayi fossil material. Based on this analysis, all supposed distinguishing morphological characteristics used to define C. guildayi can be observed in specimens of C. alleganiensis, or are based on misidentifications. Therefore, Cryptobranchus guildayi is considered to be conspecific with C. alleganiensis and taxonomically should be considered a junior synonym of the latter. The reassignment of the C. guildayi specimens to C. alleganiensis and examination of undescribed fossil specimens from the same region expands the prehistoric range of the species to the Potomac River and its tributaries and also extends the age of the species to the Irvingtonian North American land mammal age.

This study focuses on the morphometric and systematic studies of fossil vitaceous seeds recently recovered from the Gray Fossil Site (7-4.5 Ma, latest Miocene-earliest Pliocene) northeastern Tennessee. Morphologically, all fossil seeds correspond to the extant subgenus Vitis (genus Vitis) of the Vitaceae based on the smooth dorsal surface with a centrally positioned chalaza connected with a conspicuous chalaza-apex groove and short linear ventral infolds that are slightly diverged apically. A multivariate analysis based on 11 measured characters from 76 complete seeds identified three types of seeds, each representing a distinct morphotaxon. Based on comparison with modern and fossil vitaceous specimens, three new species were recognized: Vitis grayana sp. nov., Vitis lanatoides sp. nov., and Vitis latisulcata sp.nov. The close resemblance between the first two fossil grapes (Vitis grayana and Vitis lanatoides) with extant eastern Asian Vitis provides further evidence that the eastern Asian floristic elements existing in the southeastern North American flora continued to as late as late Neogene.

Since the early days of the discovery of the Gray Fossil Site (GFS), meticulous efforts to preserve the spatial data were a priority. Direct surveying of fossils prior to recovery, as well as grid mapping the site, provided relative spatial data within a square meter. Such efforts meant that even fragments and microfossils, recovered during the screening operations and eventual concentrate picking, maintained some spatial data. Available spatial data are used to identify smaller deposits within the greater system, as well as non-random distribution patterns among a number of GFS taxa. Patterns are particularly pronounced in the large-bodied taxa, Teleoceras aepysoma and the GFS mammutid, as well as microvertebrates. Results suggest that controlling factors include taphonomic constraints related to body size, proximity to near-shore or shallow areas, underlying geological features, and to a lesser extent “ecological role”. Results of this research may help guide future excavation and collection methods.

Snake vertebrae are common in the fossil record, whereas cranial remains are generally fragile and rare. Consequently, vertebrae are the most commonly studied fossil element of snakes. However, identification of snake vertebrae can be problematic due to extensive variation. This study utilizes 2-D geometric morphometrics and canonical variates analysis to 1) reveal variation between genera and species and 2) classify vertebrae of modern and fossil eastern North American Agkistrodon and Crotalus. The results show that vertebrae of Agkistrodon and Crotalus can reliably be classified to genus and species using these methods. Based on the statistical analyses, four of the fossil viperid vertebrae from Hickory Tree Cave were assigned to Crotalus horridus, one to C. adamanteus, and another to Agkistrodon piscivorus. The potential presence of the latter two species could indicate that the deposit is from a warm period during the Quaternary such as a Pleistocene interglacial or Holocene warm interval.

No description available.

The following chapters presented here use modern ecological data and modern marine systems to evaluate past marine depositional settings and the preservation potential of various environments in the geological record. While the chapters in this dissertation vary in terms of study area, sedimentary systems (carbonate vs. siliciclastic), depositional environment, and organisms, all projects are based on developing and using quantitative models to evaluate the present as a means for understanding the past. Chapter one focuses on the preservation potential of rocky intertidal environments. The rocky intertidal zone is one of the most poorly preserved fossil-rich environments in the geological record. However in most coastal marine habitats today, it is one of the most diversity rich environments. Chapter one also focuses on the analytical advantages of hierarchical sampling of gastropod communities across San Salvador Island, the Bahamas to quantify community and species level preservation potential in rocky shore environments. Chapters two and three are based on the fossil-rich sedimentary deposits from the Po coastal plain in northeastern Italy. These deposits have been widely studied in terms of their sedimentology and stratigraphy, resulting in a highly resolved sequence stratigraphic architecture. The integration of sequence stratigraphy with paleobiology can enhance our understanding of spatiotemporal biotic patterns recorded in the fossil record. Used in conjunction with the highly-resolved stratigraphic framework, biotic patterns can be used to assess depositional cycles and bathymetry through time. Chapter two integrates sequence stratigraphic patterns and paleoecological data to develop bathymetric models across fossiliferous marine successions of the Po coastal plain, Italy. Chapter three evaluates the modern ecological dataset used to derive the bathymetric models. The last chapter also explores water depth distribution for selected taxa recorded in the Quaternary sediments and observed in present-day habitats. The dissertation research explored here demonstrates that modern ecological systems are essential to evaluating past geologic events. Through direct observation and quantitative analysis, I have learned that modern and fossil communities behave differently depending on environment (e.g. energy, salinity, water depth, etc.). These variables affect the distribution of living organisms today and through my research, delineate fossil distributions through time. With these observations, new questions have arisen about the latitudinal variability of rocky intertidal fossil preservation and extrapolating the quantitative bathymetric models to deeper time intervals. These questions will lead to future endeavors and pointedly add to the field of geology and stratigraphic paleobiology. / Ph. D.

Fossil localities across the state of Tennessee and the data related to those sites were compiled from Tennessee Division of Geology Bulletin 84, titled “Tennessee’s Prehistoric Vertebrates,” and stored in a Microsoft Access geodatabase housed by the Department of Collections at the East Tennessee State University Museum of Natural History located at the Gray Fossil Site. Included in the database are forms to enter new site localities, view information about those already entered, view and add data to a master faunal list for the state, view sites repository information and store and add documents that are key-word searchable from the main menu. This database was compiled to give researchers a straightforward and easy to use means of analyzing known information about paleontological sites across the state, with the potential to be expanded worldwide. Conservation of data is crucial and can be lost over time unless data preservation efforts are made.

Rhinoceroses were an important part of North America’s Paleogene and Neogene ecosystems, with Teleoceras aepysoma being one of the last representatives of this family. Specimens of T. aepysoma from the Gray Fossil Site (GFS) possess distinct/peculiar pathologies: including a pair of fused ribs and ankylosed phalanges. A qualitative description of the pathologies in the GFS T. aepysoma, including new material, was conducted to accurately identify pathologies and make interpretations about the life history of the GFS rhinos. Analysis suggests that rheumatoid arthritis is common in the lower limb bones of GFS rhinos. Additionally, the rib and toe pathologies are more severe than anticipated, with the ribs showing multiple stages of healing indicating repeated trauma, likely being the first direct evidence of agonistic behavior in Teleoceras. This study provides a glimpse of what pathological conditions rhinocerotids may have been vulnerable to through time, as well as a baseline for future studies.

No description available.