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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Fossil Musk Turtles (Kinosternidae, Sternotherus) From the Late Miocene-Early Pliocene (Hemphillian) of Tennessee and Florida

Bourque, Jason R., Schubert, Blaine W. 01 January 2015 (has links)
The oldest fossil musk turtles, genus Sternotherus, are reported from the Hemphillian of eastern Tennessee and central Florida. Sternotherus palaeodorus, n. sp., is known from five partial shells discovered at the late Miocene-early Pliocene (7-4.5 Ma; late Hemphillian) Gray Fossil Site in Washington County, Tennessee. Sternotherus palaeodorus possesses an enlarged intergular scute, wide first vertebral scute that overlaps peripheral set 1, posteriorly extensive hypoplastron to peripheral 7 contact, and a posteriorly situated inguinal musk duct pore (characteristics more typically seen in Kinosternon). A cladistic analysis recovered S. palaeodorus within crown group Sternotherus in the strict consensus and on the stem of Sternotherus in the majority rule consensus. Sternotherus bonevalleyensis, n. sp., from the Palmetto Fauna (5.5-5 Ma; late Hemphillian) of central Florida was perhaps contemporaneous with S. palaeodorus and is known only from isolated shell fragments. It is morphologically most similar to the Sternotherus minor complex and Sternotherus depressus. Subsequent Blancan fossils from the Suwannee River of Florida represent aff. S. minor peltifer. Additionally, a fragmentary left hyoplastron of cf. Sternotherus from Haile 19A, Alachua County, Florida, could be the oldest record for the genus (ca. 9-8.5 Ma; early Hemphillian). These accounts reveal that Sternotherus was diverse and moderately well distributed geographically by its first known fossil occurrences and support previous hypotheses that the Sternotherus minor complex evolved in the Gulf coastal plain and dispersed throughout that region since at least the latest Miocene-earliest Pliocene.
32

Late Pleistocene Shrews and Bats (Mammalia: Soricomorpha and Chiroptera) From Térapa, a Neotropical-Nearctic Transitional Locality in Sonora, Mexico

Czaplewski, Nicholas J., Morgan, Gary S., Arroyo-Cabrales, Joaquín, Mead, Jim I. 01 December 2014 (has links)
Two species of shrews and four species of bats are described for Late Pleistocene fossils from Térapa, Sonora, Mexico. Shrews include Notiosorex and an indeterminate genus and species of Soricidae. Bats include several vespertilionids (Lasiurus, Antrozous pallidus, and Myotis) and a molossid (Tadarida brasiliensis). Previous interpretations based on evidence from sediments and other fossils at Térapa suggested the Late Pleistocene presence of a riparian corridor that was wetter and more tropical than at present, including a slow-moving stream, riparian forest, ponded water, marsh, and savanna, or a submerged to emergent grassland. Vertebrate fossils including a crocodylian, certain birds, and a capybara supported the more-tropical interpretation for these habitats. The bats and shrews in the Pleistocene paleofauna support these inferred paleohabitats but only weakly support the more-tropical aspect. Only one bat (Tadarida brasiliensis) has largely tropical biogeographic affinities; the others are widespread or temperate-zone taxa. None of the Neotropical families Phyllostomidae, Mormoopidae, or Natalidae that presently occur in the vicinity of Térapa are yet represented by fossils there. This fact might reflect a nonanalog Late Pleistocene fauna or might simply be due to the general rarity of bat and shrew fossils in fluvio-lacustrine deposits.
33

Evaluating Tsunami Education in Coastal Washington, USA: A 2001-2012 Review

Johnston, D., Johnson, V., Becker, J., Leonard, G., Fraser, S., Saunders, W., Wright, K., Paton, D., Gregg, C., Houghton, B., Schelling, J., Nelson, D., Crawford, G., Walker, B., Wood, N. 01 January 2014 (has links)
Improving the response capacity of coastal communities at risk to tsunami presents an on-going challenge. To meet this challenge Washington State Emergency Management has supported the development of an evaluation program since 2001 to monitor and continually improve its earthquake and tsunami education and preparedness programs. The overall conclusion of the initial studies was that the hazard education program up to that time had been successful in terms of promoting awareness of and access to information about tsunami hazard among the residents. However, despite success in disseminating hazard information, levels of preparedness were recorded at low to moderate levels. Following the initial evaluation a range of educational materials and outreach initiatives were developed to address the key research findings and ongoing evaluations have tracked changes in community preparedness. Our research and education has used multiple research and outreach approaches to bring about measureable change in the earthquake and tsunami preparedness of coastal Washington residents.
34

Paleontology of Caves

Schubert, Blaine W., Mead, Jim I. 01 December 2012 (has links)
No description available.
35

Advanced Members of the Ailuridae (Lesser or Red Pandas - Subfamily Ailurinae)

Wallace, Steven C. 01 January 2011 (has links)
This chapter deals with the advanced members of Ailuridae. A side from a few well-represented taxa such as Simocyon batalleri and Pristinailurus bristoli, the fossil record of the Ailuridae consists of mostly isolated teeth and fragmentary specimens. However, these two taxa are beginning to shed new light on this group of specialized carnivorans. The selection of the various dental characters appears to have been mosaic, with different teeth specializing at different rates (and with different focal zones). In addition, some forms specialized in hypercarnivory, while others were becoming adapted to hypocarnivory to varying degrees. It is quite likely that Simocyon's move to the trees may have directly led to the selection of features which allowed this group to exploit flowers and/or fruit (in addition to eating meat), and therefore hypocarnivory may have been a direct result of this change in lifestyle. Moreover, it appears that although both living "pandas" use their so-called "falsethumb" for feeding, each lineage acquired this unique trait via different pathways-one for feeding and one for climbing-making this one of the most fascinating examples of convergent evolution. Lastly, as demonstrated by Pristinailurus bristoli, not every member of this group remained arboreal, which may have reduced its ability to compete with other more generalized omnivores, and ultimately to the extinction of nearly every member of this group.
36

Late Quaternary Chronology and Extinction of North American Giant Short-Faced Bears (Arctodus Simus)

Schubert, Blaine W. 15 April 2010 (has links)
Eight new AMS radiocarbon dates on giant short-faced bears (Arctodus simus) from the contiguous United States are reported, and previously published dates from across North America are reviewed and discussed. The dates deemed to be most reliable are on purified collagen samples, and these serve as the basis for interpreting the late Pleistocene chronology and extinction of the species. The oldest acceptable radiocarbon date from the lower forty-eight states is 34,080 ± 480 BP from Island Ford Cave, Virginia, and the youngest is the previously reported 9630 ± 60 BP date from Bonner Springs, Kansas. An additional date of 10,921 ± 50 BP on the same Kansas specimen indicates a precision problem in the age of this individual. Regardless of this anomaly, new AMS dates of ∼10,800-11,000 BP on A. simus confirm that it existed up to the Pleistocene/Holocene transition and may have been one of the last megafaunal species to go extinct in North America. Further, these dates solidify the co-existence of these massive bears with humans of the Clovis cultural complex.
37

Evaluating Disaster Education: The National Oceanic and Atmospheric Administration’s TsunamiReady™ Community Program and Risk Awareness Education Efforts in New Hanover County, North Carolina

Horan, Jennifer, Meinhold, Stephen, Gill, Duane A., Houghton, Bruce F., Gregg, Chris E., Matheson, Tom, Paton, Douglas, Johnston, David 01 January 2010 (has links)
This chapter describes the evaluation of the TsunamiReady™-based educational materials distributed in New Hanover County, North Carolina. The authors evaluate whether educational materials about tsunami risk increased the perception of hazard risk, information, knowledge, and preparedness behaviors. There are three main findings. First, local knowledge of regional hazards remains a strong predictor of changes in attitudes and behavior. Second, educational materials about unlikely hazards have only a moderate impact. Third, information seeking and preparedness behavior is a function of general psychological attributes such as personal risk calculations. The authors argue that a community’s hazard experiences and the frequency and severity of hazard events play an important role in receptiveness to educational efforts as well as disaster preparedness.
38

Cranial Morphology and Systematics of an Extraordinary Sample of the Late Neogene Dwarf Tapir, Tapirus Polkensis (Olsen)

Hulbert, Richard C., Wallace, Steven C., Klippel, Walter E., Parmalee, Paul W. 01 March 2009 (has links)
The previously poorly known "Tapiravus" polkensis Olsen, 1960 (Mammalia, Perissodactyla, Tapiridae) is now known from abundant, well preserved specimens from both the type area in central Florida and from the Gray Fossil Site (GFS) in eastern Tennessee. The latter has produced over 75 individuals, the greatest number of tapirids from a single fossil site, including many articulated skeletons. Almost all linear measurements taken on skulls, mandibles, and cheek teeth from GFS have coefficients of variation less than 10 (most between 3 and 7), indicating the presence of a single species. However, the sample reveals considerable intraspecific variation for a few key morphologic features, including development of the sagittal crest, outline shape of the nasals, and number and relative strength of lingual cusps on the P1. The Florida sample of T. polkensis is more limited, but has the same state as the GFS sample for all preserved characters of systematic significance, and while the Florida teeth are on average smaller (especially narrower lower cheek teeth), they fall either within or just below the observed range of the Gray Fossil Site population. The new material supports a reassignment of "Tapiravus" polkensis to the genus Tapirus, and demonstrates that the geologic age of the species is significantly younger than previously thought, Hemphillian rather than Barstovian. Tapirus polkensis is the smallest known North American Tapirus, and smaller than any of the extant species in the genus, with an estimated average mass of 125 kg.
39

Late Pleistocene Giant Short-Faced Bears, Mammoths, and Large Carcass Scavenging in the Saltville Valley of Virginia, USA

Schubert, Blaine W., Wallace, Steven C. 01 December 2009 (has links)
The Saltville Valley of southwestern Virginia contains an abundance of extinct Late Pleistocene megafauna. Recent excavations in the valley produced two particularly notable discoveries, the remains of a scavenged mammoth (Mammuthus sp.) and a giant short-faced bear (Arctodus simus). The bear is the first carnivoran record from Saltville, and its large dental dimensions, dentary proportions, and exceptionally short-face, evince an exceedingly powerful bite for this individual. Mammoth remains are relatively abundant from Saltville, but the material described here preserves extreme examples of scavenging by carnivores. Based on comparisons with the feeding behavior and bone alteration patterns of extant hyenas, cats, wolves, and bears, we conclude that at least two types of large carnivorans scavenged this mammoth carcass. AMS radiocarbon dates of 14 510±55 14C yr BP on the Mammuthus and 14 853±55 14C yr BP on the A. simus demonstrate that they are nearly the same age. Very few direct radiocarbon dates on A. simus have been reported from the contiguous United States. The Saltville A. simus represents the most eastern date for the species, as well as the only date from the Appalachian Highlands.
40

Geotechnical Characterization of Sevier and Rome Shale, East Tennessee

Nandi, A., Liutkus, C. M., Whitelaw, M. J. 27 November 2009 (has links)
A complex mosaic of Sevier (Ordovician) and Rome (Cambrian) Shale are widely distributed throughout the sedimentary sequences in the southern Appalachians. These shales exhibit variable geotechnical characteristics including the strength and durability. We have investigated the factors controlling the Unconfined Compressive Strength (UCS) and Slake Durability Index (SDI) of Sevier and Rome Shale in order to better understand site-specific engineering problems associated with these shales and to predict their geotechnical behavior. The results have shown the variation in mineral content including expanding clay, calcite, gypsum, and presence of microfractures filled with calcite have significantly affected the durability and strength of shale rock mass. In order to obtain realistic estimate of time-dependent weathering patterns in the Sevier and Rome Shale, we have performed multi-cycle SDI; results have indicates that a 5-cycle SDI better estimates the disintegration pattern of shale and can be used to classify shale in terms of the degree of weathering.

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