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Full-Text Articles in Physical Sciences and Mathematics

The Anatomy And Phylogeny Of A New Large Plioplatecarpine Mosasaur From The Campanian Bearpaw Shale Of Montana (Usa), Richard A. Carr Jan 2023

The Anatomy And Phylogeny Of A New Large Plioplatecarpine Mosasaur From The Campanian Bearpaw Shale Of Montana (Usa), Richard A. Carr

Master's Theses

In 2018, a large and associated plioplatecarpine mosasaur skull, pectoral girdle, and rib cage, whose total body length may have exceeded five meters, was uncovered in the Late Campanian Bearpaw Shale of Northeast Montana (USA). Phylogenetic analysis of this specimen, MOR 10855, recovers this individual as a basal member of the genus Plioplatecarpus. This specimen, is unique in that it is estimated to be nearly twice the size of any of the other species of Plioplatecarpus found in the Western Interior Seaway during this part of the Cretaceous. While the included phylogenetic study suggests MOR 10855 represents a new …


Developing The Housing Attribute And Spatial Index (Hasi) Tool To Identify Characteristic Neighborhoods Using Variable Importance Factors Calculated Utilizing Random Forest Regression Modeling In Arcgis Pro, William A. Wallace Jan 2023

Developing The Housing Attribute And Spatial Index (Hasi) Tool To Identify Characteristic Neighborhoods Using Variable Importance Factors Calculated Utilizing Random Forest Regression Modeling In Arcgis Pro, William A. Wallace

Master's Theses

The purpose of this research is to examine the functionality in utilizing Random Forest Regression (RFR) Variable Importance (VI) values in characterizing neighborhoods based on the attributes of existing housing units by creating an automated GIS tool. An important concept that has been implemented in the past in real-estate valuation is the concept of Hedonic Price Modeling (HPM), which uses regression techniques to identify the impacts that individual attributes have on the cost of a good in a heterogenous market outside of mere utility. The benefit of this research is to produce a tool that automates the RFR process such …


The Relationship Between Climate Social Vulnerability And Asthma, Diane Nunez Jan 2023

The Relationship Between Climate Social Vulnerability And Asthma, Diane Nunez

Master's Theses

Asthma is a chronic respiratory disease that affects millions of people worldwide, the incidence and severity of asthma is influenced influenced by various factors, including air masses, and weather conditions. Asthma can also disproportionately affect different sociodemographics groups, leading to inequalities and injustices. This study used statistical analysis and GIS to analyze the spatial distribution of asthma calls and their relationship to sociodemographic traits in Wichita, KS, Tulsa, OK, and Oklahoma City, OK, and the seasonal distribution of asthma calls and their relationship to air masses. Results show that the relationship between asthma prevalence is higher among certain sociodemographic groups, …


Timing Of Diversification, Dispersal, And Biogeography Of Parrots In The Genus Amazona (Psittaciformes: Psittacidae) Throughout The Caribbean, Visualized In Gis, Christopher Kingwill Jan 2023

Timing Of Diversification, Dispersal, And Biogeography Of Parrots In The Genus Amazona (Psittaciformes: Psittacidae) Throughout The Caribbean, Visualized In Gis, Christopher Kingwill

Master's Theses

Avian fossil records from across the Caribbean (Greater and Lesser Antilles) demonstrate higher avian diversity prior to extinction events due to climate change at the end of the Pleistocene and human impact across the Caribbean throughout the Holocene. Amazon parrots (Amazona) are a diverse genus of New World parrots found throughout Central and South America, as well as the Caribbean. Their phylogeny and evolutionary history, specifically for Caribbean species, has been debated in terms of source areas in Central and South America and the timing of and number of colonization events to different islands that preceded diversification into …


Dye Tracing And The Effects Of Infrastructure In Hidden River Cave, Horse Cave, Ky, Alexa G. Franks Jan 2022

Dye Tracing And The Effects Of Infrastructure In Hidden River Cave, Horse Cave, Ky, Alexa G. Franks

Master's Theses

Hidden River Cave is a stream cave system found in Horse Cave, KY with continuous water flow of its two branches, Wheet River and East River. The infrastructure of the city of Hose Cave, KY was originally designed to utilize natural sinkholes for drainage of all wastewaters. The city uses many of these, now modified, sinkholes for wastewater disposal and storm water drainage. Historically, Hidden River Cave has been severely impacted by unmonitored dumping of contamination. To better understand and identify specific flow paths from sinkholes and infrastructure into Hidden River Cave, this study documented various sinkholes and other infrastructure, …


Using Geochemical Composition To Determine Paleo Environmental Conditions And Source Inputs In Paleozoic Rocks Within The Central Kansas Uplift Usa, Christiana Fumnanya Eziashi Jan 2022

Using Geochemical Composition To Determine Paleo Environmental Conditions And Source Inputs In Paleozoic Rocks Within The Central Kansas Uplift Usa, Christiana Fumnanya Eziashi

Master's Theses

Paleoenvironmental conditions, sediment characteristics and lateral continuity using chemostratigraphy are not well established for stratigraphic units associated with some small fields within the Central Kansas Uplift (CKU). Samples of drill cuttings recovered from six wells (Hottman #1, and Hottman-Furthmeyer#1, Yocemento #1, Mong Benno #2, Rhian #3 and Worcester #1) at 10 ft intervals between 3150 ft and 3900 ft below ground level, were processed and analyzed using X-ray fluorescence (XRF) and X-Ray diffraction (XRD). The XRF technique was used to determine elemental compositions, and XRD was used to determine mineral content. The composition of the rock cuttings was used to …


Stable Isotope Analysis Of A Platecarpus Tympaniticus (Squamata, Mosasauridae) With Actinocamax Sternbergi (Mollsuca, Belemnoidea) Reveals Possible Endothermic Thermoregulation, Mitchell Lukens Jan 2022

Stable Isotope Analysis Of A Platecarpus Tympaniticus (Squamata, Mosasauridae) With Actinocamax Sternbergi (Mollsuca, Belemnoidea) Reveals Possible Endothermic Thermoregulation, Mitchell Lukens

Master's Theses

Mosasaurs, ancient marine reptiles, dominated the late Cretaceous oceans. However, their ecological success is a contentious topic. Were they ectothermic, like their modern relatives the varanid lizards? Or endothermic like extant marine mammals? Stable isotopes can reveal temperature and physiological variances within skeletons, but do not differentiate between body temperature and ambient environmental temperature. A rare mosasaur specimen from the Smoky Hill Chalk of a partial, articulated Platecarpus tympaniticus with stomach contents of belemnites provides a possible direct temperature contrast between predator and prey. The belemnites, related to modern coleoids, are identified as Actinocamax sternbergi. These animals possessed body …


A Karst Feature Prediction Model For Prince Of Wales Island, Alaska Based On High Resolution Lidar Imagery, Alexander Lyles Jan 2021

A Karst Feature Prediction Model For Prince Of Wales Island, Alaska Based On High Resolution Lidar Imagery, Alexander Lyles

Master's Theses

Investigation into surface karst formation is significant to hazard prediction, hydrogeologic drainage, and land management. Southeast Alaska contains over 600,000 acres of mapped carbonate bedrock, and some of the fastest recorded karst dissolution in the world. The objectives of this study are to develop and compare multiple semi-automated models to map and delineate karst features from bare-earth LiDAR imagery using ArcGIS Desktop 10.7, and to apply a preliminary geostatistical analysis of sinkhole morphometric parameters to highlight potential spatial patterns of karst evolution on Prince of Wales Island, Alaska. A semi-automated approach of mapping karst features provides a dataset that minimizes …


Policy Analysis Of Emissions Cap And Trade: The United State And The European Union, Drew Bealby Jan 2021

Policy Analysis Of Emissions Cap And Trade: The United State And The European Union, Drew Bealby

Master's Theses

Effects of climate change are appearing each day therefore proactive steps need to be made to reduce these effects. The National Aeronautics and Space Administration (NASA) notes that humans producing greenhouse gases (GHGs) such as carbon dioxide (CO2), methane, and nitrous oxide are the main reason the Earth’s overall temperature is rising (NASA 2019). A policy analysis was done on the European Union Emissions Trading Scheme (EU ETS) along with comparisons to the United States’ emissions policies that are in place currently. The European Union (E.U.) itself is both an economic and political union of 27 countries in …


Ecological Controls On The Campanian Distribution Of Hesperornis (Aves: Hesperornithiformes) In The Western Interior Seaway, Blake Chapman Jan 2021

Ecological Controls On The Campanian Distribution Of Hesperornis (Aves: Hesperornithiformes) In The Western Interior Seaway, Blake Chapman

Master's Theses

The epicontinental Western Interior Seaway (WIS) of Late Cretaceous North America provided a unique marine habitat for cephalopods, fish, marine reptiles, and the foot-propelled diving seabird Hesperornis. While several predator-prey relationships among Hesperornis or other hesperornithiforms and other WIS animals have been hypothesized based on gut contents, bite marks, and coprolites/colonites, ecological relationships have not been quantitatively tested. Paleontological species distribution modeling (SDM) studies have focused on extinct non-marine taxa and marine invertebrates, with only two marine vertebrate studies of extant taxa. Here, two SDM methods were used to test the influence of vertebrate faunas, sedimentary rock type, paleogeography, …


A Karst Feature Predictability Model Within Barber County, Kansas, Gary M. Kelner Jan 2020

A Karst Feature Predictability Model Within Barber County, Kansas, Gary M. Kelner

Master's Theses

This research consisted of two topics: 1) geographic predictive models of karst features and 2), a petrographic study examining the lithology of the study area. The study area is a privately owned ranch in the Gypsum Hills of Barber County, Kansas and is known to have karst features. Two predictive models for karst features were utilized. Previously identified features, Light Detection and Ranging (LiDAR), and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery aided in the creation of these predictive models. These predictability models also used the ESRI ArcMap software platform. The data for these models consists of slope, …


Analysis Of Clastic Cave Sediment In A Fluviokarst System, Russell Cave, Northeast Alabama, Jonathan Camelo Jan 2020

Analysis Of Clastic Cave Sediment In A Fluviokarst System, Russell Cave, Northeast Alabama, Jonathan Camelo

Master's Theses

Russell Cave is part of a fluviokarst system located along the edge of the Cumberland Plateau in northeast Alabama. The cave system acts as a surface-subsurface drainage system transporting, depositing, and accumulating large influxes of terrestrial-derived materials (sediments, organic material, and magnetic minerals) into the subsurface system forming sediment traps. Five core sites along various discontinuous sediment banks were collected and sampled in 2 cm intervals. Data collection involved Red-Green-Blue (RGB) color, loss on ignition (LOI), magnetic susceptibility (MS) grain-size analysis, end member mixing analysis (EMMA), and 14C radiocarbon dating. The goals for this research were to identify the …


Weighing The Impacts Of Airbnb In Iceland: Multivariate Perspectives, Alexa Gorlick Jan 2020

Weighing The Impacts Of Airbnb In Iceland: Multivariate Perspectives, Alexa Gorlick

Master's Theses

This research sought to evaluate if the sharing economy leader, Airbnb, creates impacts that residents of Iceland feel they experience. The study also aimed to discover if rural and urban inhabitants have similar perspectives on Airbnb impacts. Airbnb’s entrepreneurial encroachment into the accommodation sector has caused a multitude of localities to manage an assortment of complex affairs. These matters are difficult to solve due to their changing, contradictory, and incomplete premise. The purpose of this research is to determine if Airbnb activity is prominent in Iceland and therefore causing the country to experience similar issues that officials are struggling to …


Gypsum Karst Speleogenesis In Barber County, Kansas Of The Permian Blaine Formation, Kaitlyn Gauvey Jan 2019

Gypsum Karst Speleogenesis In Barber County, Kansas Of The Permian Blaine Formation, Kaitlyn Gauvey

Master's Theses

Field reconnaissance examining the Permian Blaine Formation and the karst features within those rocks were conducted on two ranches in Barber County, Kansas. Karst features are developed dominantly in gypsum and include caves, sinkholes, losing streams, springs, and other surficial karst features. The Blaine Formation is known as a significant karst unit and major aquifer system in Oklahoma; however, little work has been conducted in Kansas. This study identifies the processes that lead to karst development in the Blaine Formation in Kansas and represents the first stage of a karst study to develop predictive karst models. This survey of caves …


Prospecting For Coal Bed Uranium In Kansas Through The Use Of Arcgis And Uranium Proxies, Logan Howell May 2018

Prospecting For Coal Bed Uranium In Kansas Through The Use Of Arcgis And Uranium Proxies, Logan Howell

Master's Theses

The potential implications for the discovery of coal bed uranium in Kansas not only have a significant scientific and human health interest impact, but also a possible future economic one as well. This study sought to look for coal bed uranium within the Cretaceous Dakota Formation located in north-central of Kansas. This study utilized the two coal bed uranium proxies of historic subbituminous coal production and radon, and ArcGIS to produce a field-site selection map. This map was used to pick counties within Kansas to collect samples from. Once samples were collected, they were scanned for radiation using all available …


Spatial Patterns Of Precipitation Trends In The Continental United States, 1950-2016, Shayne O'Brien May 2018

Spatial Patterns Of Precipitation Trends In The Continental United States, 1950-2016, Shayne O'Brien

Master's Theses

Identifying trends in aspects of meteorology is becoming increasingly important to understanding how climate can be expected to change, and how those affected may plan contingencies. Analyzing spatial patterns of precipitation trends allows for associations to be discovered to better understand regional climatology. For this study, daily precipitation data were collected from The National Oceanic and Atmospheric Administration (NOAA) Global Historical Climate Network (GHCN) at stations across the continental United States, with selection based on distance from each other within a state, as well as percent completeness of observation data. Two stations per state were selected, with some exceptions for …


Osteohistology And Skeletochronology Of An Ontogenetic Series Of Clidastes (Squamata: Mosasauridae): Growth And Metabolism In Basal Mosasaurids, Cyrus C. Green Jan 2018

Osteohistology And Skeletochronology Of An Ontogenetic Series Of Clidastes (Squamata: Mosasauridae): Growth And Metabolism In Basal Mosasaurids, Cyrus C. Green

Master's Theses

Clidastes was a large marine reptile from the Late Cretaceous Western Interior Seaway of North America. Though the remains of Clidastes have been found in the Cretaceous chalks and shales for over 150 years, little is known about their growth rates.

Osteohistology is a well-documented technique used to investigate growth in extinct animals. Previous histological studies of Clidastes have hypothesized higher growth rates in basal mosasaurids than varanids due to higher vascularity. These studies focused on adult specimens but did not look at ontogenetic changes in growth rates. Isotopic studies of Clidastes indicate high metabolic temperatures, leading to speculation these …


Exploring The Relationship Between The Nemaha Uplift And The Mid-Continent Rift Using 3d Mapping Visual Analysis, Faris Abanumay Jan 2018

Exploring The Relationship Between The Nemaha Uplift And The Mid-Continent Rift Using 3d Mapping Visual Analysis, Faris Abanumay

Master's Theses

The present study presents and explains the relationship between Nemaha uplift and Mid-continent rift (MCR), where the understanding of the faulting systems around the study region were extremely important with regard to finding the relationship. The Nemaha is located in Kansas State in the Central United States with a total area of about 719 square miles. It was formed around the pre- Mississippian era. The compression and rifting processes that led to formation of faults, volcanoes, ridges and oceanic plates controls the faulting in the Nemaha region. The MCR system is a major tectonic feature in North America that is …


Characterizing Basement Structures To Evaluate Their Influence On Overlaying Sedimentary Layers: Case Study Of Three Fields In The Central Kansas Uplift, Muhammad S. Karim Dec 2017

Characterizing Basement Structures To Evaluate Their Influence On Overlaying Sedimentary Layers: Case Study Of Three Fields In The Central Kansas Uplift, Muhammad S. Karim

Master's Theses

Potential field and well log data were used to investigate basement features and the overlaying sedimentary layers across four counties in the Central Kansas Uplift. The objective of this study was to (1) investigate and determine the orientation of basement structures/features, (2) estimate the depth to basement, and (3) examine the influence (if any) and relationship between the basement features and the overlaying sedimentary deposits of three oil fields in the study area. Aeromagnetic data was used to interpret and map basement features by applying derivative filters. Well log data was used to pick formation top values and create contour …


Morphometric Changes In Semicircular Canal Shape Within Theropoda (Dinosauria: Saurischia) And Their Dietary Implications, James Logan King Jul 2017

Morphometric Changes In Semicircular Canal Shape Within Theropoda (Dinosauria: Saurischia) And Their Dietary Implications, James Logan King

Master's Theses

heropods were a suborder of dinosaurs that displayed a large variety of dietary preferences throughout the Mesozoic and into the Cenozoic as modern birds. Being ancestrally carnivorous, many of the large-bodied early theropods were hypercarnivorous; however, members of Theropoda diversified their diets into omnivory and herbivory. Modern vertebrates with different dietary preferences have different spatial sensitivities to changes in head and body movement. In order to test if theropod diet plays a major role in the rostral (RSC), caudal (CSC), and lateral (LSC) semicircular canal shape, therizinosaurs, tyrannosaurids, ratites, an allosaurid, an ornithomimid, and a phorusrhacid were analyzed via 2D …


Stable Isotope Diet Analysis Of Teleoceras Fossiger From The High Plains Of Kansas, Patrick J. Wilson May 2017

Stable Isotope Diet Analysis Of Teleoceras Fossiger From The High Plains Of Kansas, Patrick J. Wilson

Master's Theses

Stable isotope geochemistry provides a way of examining both modern and ancient ecosystems. One important use of stable carbon isotopes is to determine the amount of C3 versus C4 plant biomass in the diet of herbivorous mammals. C3 plants have a more negative stable carbon isotope ratio (δ13C) than C4 plants because of the different photosynthetic pathways each type uses. These different δ13C values are preserved in the hydroxyapatite of herbivores upon consumption of the different plant types. The purpose of this study it to use δ13C values from serial samples of tooth enamel from six isolated permanent molars of …


The Relationship Among Suture Complexity, Shell Form, And Stratigraphic Formation In Ammonites Of The Western Interior Seaway, Darrah Jorgensen May 2017

The Relationship Among Suture Complexity, Shell Form, And Stratigraphic Formation In Ammonites Of The Western Interior Seaway, Darrah Jorgensen

Master's Theses

Throughout ammonite evolution, shell suture patterns grew increasingly more complex, but the purpose of these sutures has long been debated. One hypothesis is that suture complexity is related to the structural integrity of the shell under pressure. To test this hypothesis, suture complexity was compared to shell form and stratigraphic formation to determine if there were significant differences in suture complexity, as a proxy for structural integrity, among shell forms or stratigraphic formations. Highly complex sutures might have allowed for the tightly coiled form of many ammonites, an advantage compared to less coiled forms because the pressure is distributed over …


Uas-Collected Multispectral Imagery For The Identification Of Rangeland Vegetation In A Southern Mixed-Grass Prairie, Adam Rusk May 2017

Uas-Collected Multispectral Imagery For The Identification Of Rangeland Vegetation In A Southern Mixed-Grass Prairie, Adam Rusk

Master's Theses

The interest in using unmanned aerial systems (UAS) for remote sensing of natural resources and ecology has grown rapidly in recent years and continues to develop. Recent improvements in the cost, size, and accessibility of consumer-grade UASs are now facilitating image collection on low-flying UAS platforms. Rangelands provide a unique opportunity to explore the uses of UAS remote sensing due to their large spatial extent and spatial and temporal heterogeneity. This study focuses on the use of UAS’s to identify rangeland vegetation in a southern mixed-grass prairie in Kansas. Two primary questions were asked: 1) Do small UASs with low-cost …


Analysis Of Big Creek Aquifer Alluvial Facies And Associated Phreatic Surface Contour Maps Hays, Ellis County, Kansas, Krisopher John Neuhauser May 2017

Analysis Of Big Creek Aquifer Alluvial Facies And Associated Phreatic Surface Contour Maps Hays, Ellis County, Kansas, Krisopher John Neuhauser

Master's Theses

Three contour maps of groundwater elevation levels below Hays, Kansas generated in 2016 show that the phreatic surface in eight monitoring wells declined 3.6 inches to 1 foot 9.6 inches over a three-month period of July, August, and September. They also indicate that groundwater flows in curvilinear directions toward Big Creek. Analyses of ten north-south oriented structural cross sections of the alluvial fill beneath the central region of Hays provide evidence of buried low-sinuosity and meandering streams, floodplains, and possibly adjoining tributaries and abandoned channels. Correlation of the more porous and permeable sand and gravel facies along a northwest to …


Hydrogeological Study Of A Municipal Groundwater Well Field In Central Kansas, Tyler Saryerwinnie May 2017

Hydrogeological Study Of A Municipal Groundwater Well Field In Central Kansas, Tyler Saryerwinnie

Master's Theses

The City of Victoria is a small town of approximately 1,200 people situated in Central Kansas. Along with other communities in Kansas, recent drought has made the issue of water quality and availability a pressing concern with local officials. This city relies heavily on the use of ground-water wells located south of the town near the Big Creek channel. It is the purpose of this study to define the hydrogeological conditions effecting the City’s well field, and in turn apply this information to define an area of influence and outline potential hazards for the well field. Utilizing previous studies, along …


Dental Microwear Variation In Teleoceras Fossiger (Rhinocerotidae) From The Miocene (Hemphillian) Of Kansas, With Consideration Of Masticatory Processes And Enamel Microstructure, Kelsie Abrams Jul 2016

Dental Microwear Variation In Teleoceras Fossiger (Rhinocerotidae) From The Miocene (Hemphillian) Of Kansas, With Consideration Of Masticatory Processes And Enamel Microstructure, Kelsie Abrams

Master's Theses

Dental microwear analysis is the study of microscopic features on the surfaces of teeth, and is used to reconstruct and analyze diet in extinct and extant animals. Microwear analysis on ungulates is typically conducted on the paracone or protoconid of the second molar, as these cusps are usually the first point of contact between upper and lower teeth during the chewing stroke. However, the exact method of mastication varies in different groups of ungulates, and the influence of mastication on the location and production of microwear features has been studied very little. Additionally, the role of highly specialized enamel microstructure …


Petrophysical Attributes, Depositional Environment, And Diagenetic History Of A Mississippian Interval From Mcpherson County, Kansas, Usa, John Hunter Green May 2016

Petrophysical Attributes, Depositional Environment, And Diagenetic History Of A Mississippian Interval From Mcpherson County, Kansas, Usa, John Hunter Green

Master's Theses

Siliceous – carbonate intervals in the Mid-­‐Continent are proven producible hydrocarbon reservoirs, however they have been understudied compared to more classic type reservoirs because of difficulties in characterization and correlations due to the heterogeneity and complex nature of their lithofacies. Understanding the characteristics of siliceous – carbonate lithofacies through macro and micro scale analysis can enhance the assessment of reservoir attributes and quality. Core, thin sections, and well logs were used to determine characteristics of a Mississippian (Osagean – Meramecian) interval (2,906 ft. and 2,946 ft.) from Canton SWD 1-36 located in McPherson County, Kansas, USA. Qualitative and quantitative analyses …


An Integrated Analysis Of The Oppliger And Harkness Oil Fields Using Well Log Data And 3d Seismic Data, Casey B. Langdon Jan 2016

An Integrated Analysis Of The Oppliger And Harkness Oil Fields Using Well Log Data And 3d Seismic Data, Casey B. Langdon

Master's Theses

Subsurface mapping from well points and 3D seismic interpretation are essential techniques used to study and locate structures in petroleum exploration. In this study, subsurface structure maps, detailed well log facies analysis, 3D seismic interpretation, and attribute analysis were used to map a Mississippian interval and middle Pennsylvanian age interval from two oil fields in Ness County, Kansas. The objective of this study is to analyze formation properties and facies distribution, map middle Pennsylvanian Cherokee channel deposits using seismic data, and to construct a structural model highlighting important features effecting oil production. Results show that the stratigraphic succession of this …


3d Geometric Morphometrics In Modern And Extinct Foot-Propelled Diving Birds: An Evaluation Of The Tarsometatarsus For Species Identification, Mackenzie E. Kirchner-Smith Nov 2015

3d Geometric Morphometrics In Modern And Extinct Foot-Propelled Diving Birds: An Evaluation Of The Tarsometatarsus For Species Identification, Mackenzie E. Kirchner-Smith

Master's Theses

Hesperornithiformes (Aves: Ornithurae) were flightless foot-propelled diving birds that lived during the Late Cretaceous and have a good fossil record compared to most Mesozoic birds. Extinct taxa are often identified using fragmentary or isolated specimens, and several species of Hesperornis have been named from the morphology of the tarsometatarsus, often relying on size for taxonomic differentiation. However, little has been done to examine intraspecific variation in this bone and evaluate its use for taxonomic identification. To test for intraspecific and interspecific variation in the tarsometatarsus of hesperornithiforms, variation in extant members of the foot-propelled diving Gaviidae (loons) and Podicipedidae (grebes) …


Redescription Of A Specimen Of Pentaceratops (Ornithischia: Ceratopsidae) And Phylogenetic Evaluation Of Five Referred Specimens From The Upper Cretaceous Of New Mexico, Joshua J. Fry Jul 2015

Redescription Of A Specimen Of Pentaceratops (Ornithischia: Ceratopsidae) And Phylogenetic Evaluation Of Five Referred Specimens From The Upper Cretaceous Of New Mexico, Joshua J. Fry

Master's Theses

Pentaceratops sternbergi is a late Campanian ceratopsian predominately known from the San Juan Basin in New Mexico. Previous specimen descriptions and cladistic analyses are based on partial skulls and composite specimens, which places Pentaceratops as an intermediate form between Chasmosaurus and Triceratops. Recent reports have questioned the taxonomic validity of several referred specimens, leading to taxonomic confusion. To address taxonomic issues, Museum of Northern Arizona specimen MNA V1747 (formerly MNA Pl. 1747) is redescribed and included in the first specimen-based phylogenetic analysis. Additional preparation since the initial description has made available additional skull elements and revealed MNA V1747 to be …