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Late Quaternary Dragon Lizards (Agamidae: Squamata) From Western Australia, Julie Rej 2017 East Tennessee State University

Late Quaternary Dragon Lizards (Agamidae: Squamata) From Western Australia, Julie Rej

Electronic Theses and Dissertations

Fossil Agamidae from Western Australia have been the subject of limited study. To aid in fossil agamid identification, Hocknull (2002) examined the maxilla and dentary of several extant species from Australia and determined diagnostic characters for various species groups. In the study here, fossil agamids from two localities in Western Australia, Hastings Cave and Horseshoe Cave, were examined, grouped, and identified to the lowest unambiguous taxonomic level. Morphometric analyses were conducted to compare morphotypes, and find additional diagnostic characters. From Hastings Cave there were two maxilla morphotypes and three dentary morphotypes. Based on identifications, taxa present at this locality were ...


The Homology And Phylogeny Of The Diploporita (Blastozoa: Echinodermata), Sarah Lynne Sheffield 2017 University of Tennessee, Knoxville

The Homology And Phylogeny Of The Diploporita (Blastozoa: Echinodermata), Sarah Lynne Sheffield

Doctoral Dissertations

Evolutionary relationships of extinct echinoderms are poorly understood, especially within stem-bearing blastozoans, a large group of echinoderms with unique respiratory structures and feeding brachioles. They were highly experimental in their body plans and very unlike echinoderms today (e.g., sea urchins). Many of the blastozoan subgroups recognized in recent classifications do not represent clades (natural associations of organisms derived from a single ancestor); they are either grades of organization or groups united by superficially similar features. Consequently, these ‘traditional’ groupings cannot be used to analyze evolutionary questions, such as biogeography or rates of evolution. This problem is highlighted within the ...


Behavioral Paleoecology Of Lower Cambrian Deposit Foragers: Reinterpreting Looping And Meandering Traces Using Optimal Foraging Theory And Quantitative Analysis, Zachary Andrew Jensen 2017 University of Nevada, Las Vegas

Behavioral Paleoecology Of Lower Cambrian Deposit Foragers: Reinterpreting Looping And Meandering Traces Using Optimal Foraging Theory And Quantitative Analysis, Zachary Andrew Jensen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The early Cambrian was a period of transition during which the seafloor environment was changing from a microbial-mat-dominated environment to a bioturbation-dominated environment. The result was a patchy landscape of variable food resources for foraging burrowers to exploit. Looping trace fossils, such Psammichnites gigas and Taphrhelminthopsis nelsoni, appear in strata worldwide during this transitional period, and the ecological niche they filled is a subject of debate among ichnologists. The objectives of this study are (1) to determine the foraging strategies preserved by looping traces through the application of optimal foraging theory and quantitative analysis, and (2) use those results to ...


Understanding Feathered Dinosaurs, Michael D. Sprague 2017 Cedarville University

Understanding Feathered Dinosaurs, Michael D. Sprague

The Research and Scholarship Symposium

Young-earth creationists hold to separate creations of birds and land animals due to a literal interpretation of Genesis 1:20-25, which describes their creations on different days. As such, they oppose the conventional model of theropod-to-bird evolution. For many years, there were few Mesozoic birds known, namely Hesperornis and Icthyornis. Specimens such as Archaeopteryx, found in 1861, seemed to strengthen the argument for the proposed transition. However, even after John Ostrom reinvigorated the idea of dinosaur-to-bird evolution in 1960 with the discovery of Deinonychus, evidence of this transition was still sparse. In the 1990’s, exquisitely-preserved dinosaur fossils began to ...


A Correlation And Stratigraphy Of Detailed Measured Core Sections Of The Waynesville And Liberty Formations (Katian; Richmondian) - Transecting Warren, Clinton, And Fayette Counties Of Ohio, Mark P. Guilliams 2017 Cedarville University

A Correlation And Stratigraphy Of Detailed Measured Core Sections Of The Waynesville And Liberty Formations (Katian; Richmondian) - Transecting Warren, Clinton, And Fayette Counties Of Ohio, Mark P. Guilliams

The Research and Scholarship Symposium

The stratigraphy of the Cincinnatian is difficult to understand and interpret which has resulted in various models for deposition ranging from a layer cake model with continuous beds to completely discontinuous beds. The interest of this study is the Liberty and Waynesville Formations (previously part of the Bull Fork Formation); these are Late Ordovician (Katian; Richmondian) units of predominantly limestone and shale. This project assesses the continuity of fine scale beds within these formations across a small area (approx. the size of Ohio’s Clinton County) by correlating measured sections from drill cores. The project involved the study of five ...


A Description Of A New Allosaurus (Dinosauria: Theropoda) Skull With Comparison To Additional Specimens, Michael D. Sprague 2017 Cedarville University

A Description Of A New Allosaurus (Dinosauria: Theropoda) Skull With Comparison To Additional Specimens, Michael D. Sprague

The Research and Scholarship Symposium

Allosaurus was a genus of large theropod dinosaur from the Late Jurassic Period (Kimmeridgian to early Tithonian). The history of the taxonomic classification of Allosaurus species is muddled at best, and the number of recognized species varies significantly between researchers. Most Allosaurs from the Morrison Formation are typically lumped into a single species, Allosaurus fragilis. Given the amount of variation seen in Allosaurs through the Morrison, the genus may more diverse than generally recognized. A nearly complete Allosaurus skull (CM 279) located in the Creation Museum in Petersberg, KY is described, with comparison of its skull morphology to two other ...


Understanding Feathered Dinosaurs, Michael D. Sprague 2017 Cedarville University

Understanding Feathered Dinosaurs, Michael D. Sprague

The Research and Scholarship Symposium

Young-earth creationists hold to separate creations of birds and land animals due to a literal interpretation of Genesis 1:20-25, which describes their creations on different days. As such, they oppose the conventional model of theropod-to-bird evolution. For many years, there were few Mesozoic birds known, namely Hesperornis and Icthyornis. Specimens such as Archaeopteryx, found in 1861, seemed to strengthen the argument for the proposed transition. However, even after John Ostrom reinvigorated the idea of dinosaur-to-bird evolution in 1960 with the discovery of Deinonychus, evidence of this transition was still sparse. In the 1990’s, exquisitely-preserved dinosaur fossils began to ...


Results Of Test-Hole Drilling For Observation Well Planning In The Upper Loup Natural Resources District, Fall 2016, Douglas Hallum, Sue Olafsen Lackey 2017 University of Nebraska-Lincoln

Results Of Test-Hole Drilling For Observation Well Planning In The Upper Loup Natural Resources District, Fall 2016, Douglas Hallum, Sue Olafsen Lackey

Conservation and Survey Division

The High Plains Aquifer underlies much of Nebraska (Figure 1). It is the primary source of groundwater within the Upper Loup Natural Resources District (ULNRD) of central Nebraska (Figure 2). Water derived from the aquifer is an important natural resource for the area and supplies water for recreation, wildlife and agriculture, as well as domestic, municipal, and industrial uses. A general lack of water level observations in the region (Figure 3), recently developed groundwater irrigated acres along the upper Calamus River (Figure 4), falling spring water levels measured in existing irrigation wells (Figure 5), and a stable to falling stream ...


Basic Meteorological Data Derived 30-Year Normas (1981-2010) Of Actual Evapotranspiration Rates In Nebraska, Usa, Jozsef Szilagyi 2017 University of Nebraska-Lincoln

Basic Meteorological Data Derived 30-Year Normas (1981-2010) Of Actual Evapotranspiration Rates In Nebraska, Usa, Jozsef Szilagyi

Conservation and Survey Division

No abstract provided.


A Unique Petroglyph Carving On The Shawangunk Ridge, Lower Hudson Valley, New York, Howard R. Feldman 2017 Touro College

A Unique Petroglyph Carving On The Shawangunk Ridge, Lower Hudson Valley, New York, Howard R. Feldman

Lander College for Women - The Anna Ruth and Mark Hasten School Publications and Research

A unique circular petroglyph from the Shawangunk Ridge in the lower Hudson Valley, New York was found carved into the resistant metaconglomerate/quartzitic rock not far from Mohonk Mountain House. The Shawangunk Formation crops out near Rosendale, New York and extends in a general southwestward direction accessible along Route 17 near Wurtsboro, again at the Delaware Water Gap and then can be traced in into Pennsylvania and Virginia. The ridge and surrounding area (e.g. Wallkill Valley) is lacking in chert, a vital raw material used in the carving of petroglyphs (Feldman, et al., 2016). However, there are numerous other ...


Dielasma Or Tunethyris? A Taxonomic Conundrum, Howard R. Feldman, Talia J. Belowich, Tova Braver, Sarah Laks 2017 Touro College

Dielasma Or Tunethyris? A Taxonomic Conundrum, Howard R. Feldman, Talia J. Belowich, Tova Braver, Sarah Laks

Lander College for Women - The Anna Ruth and Mark Hasten School Publications and Research

A new species of a dielasmid brachiopod from the Triassic Saharonim Formation of Makhtesh Ramon, southern Israel, was discovered in Anisian-Ladinian limestones that alternate with calcareous shales. The environment of deposition was an open shelf with normal salinity. The new species is homeomorphic with Paleozoic forms, but may not belong to the genus Dielasma; however, it may be a species of Tunethyris, a Triassic genus from Tunisia. If the Triassic specimens belong to the Paleozoic genus Dielasma, an important new Lazarus genus is added to the systematic literature. However, if the specimens belong to the Triassic Tunethyris, there are important ...


Paleoecology Of Foraminifera From The Late Miocene - Early Pliocene Pullen And Saint George Formations, Northwestern California, Trenton J. Ryan 2017 Humboldt State University

Paleoecology Of Foraminifera From The Late Miocene - Early Pliocene Pullen And Saint George Formations, Northwestern California, Trenton J. Ryan

Theses and projects

The Pullen and Saint George formations are coeval late Miocene-early Pliocene sedimentary formations in northwestern California. The type localities of both formations were studied from a micropaleontologic perspective that focused primarily on Foraminifera, but with additional observations of other fossil groups to reconstruct their past depositional environments. The results obtained in this study provided a photomicrographic inventory of the microfossils from both formations, aided in investigating changes in paleobathymetry of the formations during the late Miocene and early Pliocene based on Foraminifera, and allowed for interpretation of paleoecological signals from the foraminiferan associations. Foraminifera have not been previously described in ...


Geometric Morphometric Differentiation Of Two Western Usa Lizards (Phrynosomatidae: Squamata): Uta Stansburiana And Urosaurus Ornatus, With Implications For Fossil Identification, Julie Rej, Jim I. Mead 2017 East Tennessee State University

Geometric Morphometric Differentiation Of Two Western Usa Lizards (Phrynosomatidae: Squamata): Uta Stansburiana And Urosaurus Ornatus, With Implications For Fossil Identification, Julie Rej, Jim I. Mead

Bulletin of the Southern California Academy of Sciences

Squamate fossil identification has been challenging due to the incomplete understanding and sometimes complete lack of osteological research of extant species. Here we compared the maxilla of two similar species of phrynosomatids: Uta stansburiana (Common Side-blotched Lizard) and Urosaurus ornatus (Ornate Tree Lizard). Through landmark-based geometric morphometric analyses, we determined which characters significantly separated the two species. A principle component analysis (PCA) and a stepwise discriminant function analysis (DFA) were conducted, in which we compared 15 landmarks between U. stansburiana and U. ornatus. Both the PCA and stepwise DFA showed separation between the two species. The stepwise DFA selected five ...


Arctica Islandica Shell Growth And Geochemical Records From Northern Norway As North Atlantic Marine Climate Proxies For The Last Millennium, Madelyn Mette 2017 Iowa State University

Arctica Islandica Shell Growth And Geochemical Records From Northern Norway As North Atlantic Marine Climate Proxies For The Last Millennium, Madelyn Mette

Graduate Theses and Dissertations

Paleoclimate proxy records are needed to better understand the behavior of various components of Earth’s complex climate system across major climate transitions of the past. Such records can also provide benchmarks to test climate models and interpret the evolution of climate forcing, feedbacks, and interactions in the past, present, and future. Development of high-resolution, high-latitude records of climate change such as those presented in this dissertation, provide insight to highly sensitive regions where very few lengthy instrumental records exist. This dissertation presents shell growth and geochemical records from the long-lived marine bivalve, Arctica islandica, from northern Norway to investigate ...


2016 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach, Connie Reimers-Hild 2017 University of Nebraska-Lincoln

2016 Nebraska Water Leaders Academy - Final Report, Mark E. Burbach, Connie Reimers-Hild

Conservation and Survey Division

The effective management of Nebraska’s water resources is evermore challenged by variations in weather, climate, technology, socioeconomic policies, and regulation. Anthropogenic climate change, declining water tables and stream flows, increasing demands on freshwater, aging water infrastructure, fiscal constraints, and impacts on aquatic organisms are particularly imminent challenges in Nebraska and around the world (Pahl-Wostl et al., 2013; Pittock et al., 2008; USACE, 2010). Sustaining freshwater ecosystem services in the face of emerging environmental threats presents an immense societal dilemma worldwide (Pittock et al., 2013; Rockström et al., 2009, Millenium Ecosystem Assessment, 2005). The rapidly changing conditions of water resources ...


Nebraska, Usa: Wonderful Fossils, Natural History Museums And Public Art Depicting Fossils, Robert F. Diffendal Jr 2017 University of Nebraska-Lincoln

Nebraska, Usa: Wonderful Fossils, Natural History Museums And Public Art Depicting Fossils, Robert F. Diffendal Jr

Robert F. Diffendal, Jr., Publications

Nebraska is known by vertebrate palaeontologists as the place in North America where there is a very complete Cenozoic geologic record of mammalian evolution over the last thirty-five million years or so. All you have to do is visit any of the many major natural history museums in the USA and in many countries around the world, including the UK, to see fossil skulls, articulated skeletons and large slabs of rock containing bones of fossil mammals from Nebraska to verify this assertion. Nebraska is also the site of Cretaceous rocks containing the oldest known Cretaceous fossil flower and many other ...


Locomotion And Skeletal Morphology Of Late Cretaceous Mosasaur, Tylosaurus Proriger, Jesse A. Carpenter 2017 Georgia Southern University

Locomotion And Skeletal Morphology Of Late Cretaceous Mosasaur, Tylosaurus Proriger, Jesse A. Carpenter

University Honors Program Theses

Mosasaurs (Reptilia: Squamata) are apex marine predators from the Late Cretaceous (Turonian to Maastrichtian) epicontinental seas of North America, Africa, Europe, and Asia. From previous studies, it has been suggested that this group trends towards increased rib compactness, lengthening and increased posterior inclination of neural spines of intermediate and terminal caudal vertebrae to support a caudal fluke, and a transition from anguilliform to carangiform locomotion, closer to thunniform in pelagic adapted species. This study examined multiple Tylosaurus specimens using centrum length/width (CL/CW) and width/height (CW/CH) ratios along with neural spine height and angle of posterior inclination ...


Preservation Of Sea Anemone Burrows In Silurian (~432 Million Years Old) Carbonate Rocks Of Southeastern Indiana, Usa, Marissa Tomin 2017 The University of Akron

Preservation Of Sea Anemone Burrows In Silurian (~432 Million Years Old) Carbonate Rocks Of Southeastern Indiana, Usa, Marissa Tomin

Williams Honors College, Honors Research Projects

Preservation of trace fossils (ichnofossils) in siliciclastic environments is often quite different from preservation in carbonate environments, representing an important source of variation that must be well understood in order to enhance interpretations of paleoenvironments and paleoecology. This study focuses on Conostichus, a relatively common burrow constructed by solitary sea anemones. These trace fossils are generally well-preserved (i.e., they display detailed external features) in siliciclastic rocks but are typically little more than conical masses in carbonate rocks. However, certain specimens recovered from the middle Silurian Massie Formation at the Napoleon quarry of southeastern Indiana are composed entirely out of ...


Lilliput Effect Dynamics Across The Cretaceous-Paleogene Mass Extinction: Approaches, Prevalence, And Mechanisms, Matthew Brett Jarrett 2016 University of South Florida

Lilliput Effect Dynamics Across The Cretaceous-Paleogene Mass Extinction: Approaches, Prevalence, And Mechanisms, Matthew Brett Jarrett

Graduate Theses and Dissertations

An organism's body size entails both physiological and ecological costs. Furthermore, as a parameter in analyzing organisms, it represents a fundamental and essential morphometric character. Reductions in size following mass extinction is a commonly observed phenomenon in the fossil record. This study examines the evolutionary significance of this phenomenon termed the: 'Lilliput Effect' by proposing that it represents a rapid evolutionary response to altered selection pressures during a mass extinction. This primary hypothesis is evaluated against two additional hypotheses of size reduction: 1) stunted growth as a response to stressed ecosystems, and/or 2) mass extinctions are size selective ...


Early Miocene Quantitative Calcareous Nannofossil Biostratigraphy From The Tropical Atlantic, Waheed A. Albasrawi 2016 University of Nebraska-Lincoln

Early Miocene Quantitative Calcareous Nannofossil Biostratigraphy From The Tropical Atlantic, Waheed A. Albasrawi

Dissertations & Theses in Earth and Atmospheric Sciences

Quantitative analysis for the Lower Miocene of Ocean Drilling Program Hole 959A from the West African margin was performed to document all the calcareous nannofossil biostratigraphic events present. Combined with data from previous investigations of the Lower Miocene from the tropical Atlantic, this research identifies and tests the viability of markers used in current zonation scheme, identifies alternative markers for age boundaries, and examine statistically the most probable order of event in the Lower Miocene using the Ranking and Scaling method (RASC).

The examination of Hole 959A was performed on a 112 samples. Seven additional sites that collectively span the ...


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