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Full-Text Articles in Life Sciences

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 …


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 …


An Investigation Into Historical And Contemporary Breeding Occurrence Of The Ferruginous Hawk In Kansas, Erica Clark Jan 2021

An Investigation Into Historical And Contemporary Breeding Occurrence Of The Ferruginous Hawk In Kansas, Erica Clark

Master's Theses

The Ferruginous Hawk (Buteo regalis) is the largest Buteo species occurring in grasslands, nesting along bluffs, buttes and isolated trees. In Kansas, the Ferruginous Hawk is listed as a Species of Greatest Conservation Need, Tier II. A previous study on Ferruginous Hawks nesting in Kansas during the years of 1979 to 1987, with sporadic visits from the 1990s to 2000, revealed that the most productive nesting territories were inaccessible to predators, placed on rocky ledges and the surrounding landscape was over 50% rangeland. I revisited 82 of the 111 historic nest territories in the summers of 2019 and …


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, …


An Assessment Of Convergence In The Feeding Morphology Of Xiphactinus Audax And Megalops Atlanticus Using Landmark-Based Geometric Morphometrics, Edward Chase Shelburne Jan 2020

An Assessment Of Convergence In The Feeding Morphology Of Xiphactinus Audax And Megalops Atlanticus Using Landmark-Based Geometric Morphometrics, Edward Chase Shelburne

Master's Theses

Convergence is an evolutionary phenomenon wherein distantly related organisms independently develop features or functional adaptations to overcome similar environmental constraints. Historically, convergence among organisms has been speculated or asserted with little rigorous or quantitative investigation. More recent advancements in systematics has allowed for the detection and study of convergence in a phylogenetic context, but this does little to elucidate convergent anatomical features in extinct taxa with poorly understood evolutionary histories. The purpose of this study is to investigate one potentially convergent system—the feeding structure of Xiphactinus audax (Teleostei: Ichthyodectiformes) and Megalops atlanticus (Teleostei: Elopiformes)—using a comparative anatomical approach to assess …


Effects Of Fragmentation On Species Retention In National Parks, Liz Tanner Jan 2019

Effects Of Fragmentation On Species Retention In National Parks, Liz Tanner

Master's Theses

The North American landscape is becoming increasingly fragmented, resulting in habitat patches with decreased area and increased isolation. Often, these patches exist as protected areas, such as national parks. The Theory of Island Biogeography is frequently used as a model for these patches, where each park serves as an ‘island’ surrounded by a ‘sea’ of human-altered habitats. As such, species richness and extinctions in a park might be explained by its area. For this study, I used regression models to examine the relationship between richness and area, as well as extinctions and area, for mammals and birds in national parks. …


The Effect Of Vegetative Structure On Nest-Burrow Selection By The Western Burrowing Owl: Comparing Traditional Methods To Photogrammetry With An Unmanned Aerial System, Dylan J. Steffen Jan 2019

The Effect Of Vegetative Structure On Nest-Burrow Selection By The Western Burrowing Owl: Comparing Traditional Methods To Photogrammetry With An Unmanned Aerial System, Dylan J. Steffen

Master's Theses

The shortgrass prairie ecoregion in the United States has been reduced to 52% of its historical extent, contributing to reduced habitat for native species. One such species is the Burrowing Owl (Athene cunicularia). The Western Burrowing Owl subspecies (A. c. hypugaea) is listed as a Species of Special Concern in nearly every western and midwestern state, including Kansas where it is designated as a Tier II Species of Greatest Conservation Need. Habitat destruction due to conversion to cropland, increasing use of pesticides, and reduction in burrowing mammal abundance are the primary threats that have led to …


Incorporating Multi-Spectral Imaging Into Long-Term Upland Breeding Bird Monitoring, Kyle William Schumacher Jan 2018

Incorporating Multi-Spectral Imaging Into Long-Term Upland Breeding Bird Monitoring, Kyle William Schumacher

Master's Theses

Quivira National Wildlife Refuge in Kansas, United States partnered with Fort Hays State University Hays, KS in 2014 to begin a collaborative research project that aimed to develop a long-term monitoring protocol guided by the Comprehensive Conservation Plan for the refuge published in 2013. This plan identified specific wildlife taxa underrepresented in management impact assessments throughout the property. As a result of this plan, surveys were established to monitor interactions between upland breeding birds and the vegetation community. I conducted point count surveys in 2016, 2017, and 2018 for 122 observation points across four transects. I measured seventeen vegetation variables …