Paleontology Commons^™

Geology, Paleoecology And Vertebrate Biostratigraphy Of The Hell Creek Formation, Carter County, Montana, Usa, Joshua Collin Mathews

Graduate Research Theses & Dissertations

The Hell Creek Formation of the Northern Great Plains records one of the greatest mass extinction events in Earth’s history, bringing to a close the reign of the dinosaurs at the end of the Cretaceous period. This rock unit comprises one of the most studied geological formations in the world and is one of the few locations on the planet that preserve terrestrial deposits containing ejecta from the bolide impact that slammed into the Yucatan Peninsula 66 million years ago. This profound event in the geologic record has led to numerous studies of paleobiotas, climate change, ecosystem recovery dynamics, and …

Microbial Mats In Dinosaur Ichnocoenoses, Nora Noffke, Paul C. Murphey, Roger C. Buntin, Martin G. Lockley

OES Faculty Publications

Until now, the significance of microbial mats in preservation of dinosaur tracks and in reconstructing the palaeoenvironment in which dinosaurs roamed was rarely studied. Dinosaur tracks are commonly found close to ancient aquatic bodies where moist sediment had once allowed footstep registration. At such sites, epibenthic or endobenthic microbial mats may have developed as well and may have led to exquisite track preservation. Microbial mats in coastal, lacustrine or flood plain environments cause ‘microbially induced sedimentary structures—MISS’, which are micobialites found in sandy or evaporitic settings. The microbial structures record environmental parameters including meteorological conditions that existed at the time …

Conservation And Survey Division 2024 Annual Report, R.M. Joeckel, Michele Waszgis

Conservation and Survey Division: Faculty and Staff Publications

The Conservation and Survey Division of the University of Nebraska - Lincoln is the agency designated by statute to investigate and interpret the geologically related natural resources of the State, to make available to the public the results of these investigations, and to assist in the development and conservation of these resources. It consists of program areas in geology, water, soils and remote sensing-geographic information systems.

Early Holocene Interaction Of Aeolian, Alluvial, And Lacustrine Processes In A Dune-Dammed Valley In The Central Nebraska Sand Hills, Gpsia Mahoney, R. D. Mandel, P.R. Hanson, Sherilyn Fritz

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Stratigraphy And Osl Chronology Of Lunette Deposits Indicates That Nebraska’S Rainwater Basins Formed By Aeolian Deflation Between 39 And 25 Ka, P.R. Hanson, Robert Matthew Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Visualization Of Paleocurrents On A Web Application Using Gplates, Anjan Sapkota

MS in Computer Science Theses

Paleocurrents are flow directions derived from features of sedimentary rocks that reveal the direction of the current of wind or water that deposited the sediment. In 2015, Brand et al. created a global database of paleocurrents, which contains over 1,000,000 measurements worldwide: North America, South America, Australia, Great Britain, parts of Western Europe, China, Africa are fairly well represented; Antarctica, Eastern Europe, and Asia are modestly represented and Russia is poorly represented. The contribution of this thesis is a web application that uses the GPlates’ Application Programming Interface (API) to visualize global paleocurrents through time in an interactive way based …

A Day In The Badlands: A 52 Million-Year-Old Safari Adventure, Devra Hock-Reid, Judy Diamond, Jenn Paul

Zea E-Books Collection

with Amy Chew, Christopher Gilbert, Ross Secord, and Stephen Chester

Illustrations by Jenn Paul • Book design by Aaron Sutherlen

About the Badlands Fossils -- This story tells about the fossils of ancient animals found in the Wind River and Bighorn basins of Wyoming. Wyoming’s rich fossil record tell us about amazing animals from millions of years ago. About 66 million years ago, an asteroid slammed into the Earth, causing devastating changes that led to the extinction of dinosaurs. As the planet began to recover, it was much warmer than today, allowing palm trees and other tropical plants to grow …

Traittrainr: Accelerating Large-Scale Simulation Under Models Of Continuous Trait Evolution, Jenniffer Roa Lozano, Mataya Duncan, Duane D. Mckenna, Todd A. Castoe, Michael Degiorgio, Richard Adams

Entomology and Plant Pathology Faculty Publications and Presentations

Abstract

The scale and scope of comparative trait data are expanding at unprecedented rates, and recent advances in evolutionary modeling and simulation sometimes struggle to match this pace. Well-organized and flexible applications for conducting large-scale simulations of evolution hold promise in this context for understanding models and more so our ability to confidently estimate them with real trait data sampled from nature. Results

We introduce TraitTrainR, an R package designed to facilitate efficient, large-scale simulations under complex models of continuous trait evolution. TraitTrainR employs several output formats, supports popular trait data transformations, accommodates multi-trait evolution, and exhibits flexibility …

3d Reconstruction And Comparative Anatomical And Kinematic Analyses Of The Foot Of Archaeopteryx, Alexander M. Kirk

USF Tampa Graduate Theses and Dissertations

Research on the evolution of dinosaur flight has long been dominated by the wing, often overlooking the foot. The foot of Archaeopteryx, the “icon of evolution”, thus offers a unique opportunity to investigate this critical evolutionary stage. Chapter I of this dissertation integrates advanced 3D reconstruction techniques, combining photogrammetry with X-ray data, to create a high-resolution model of the foot of the Thermopolis specimen of Archaeopteryx for visualization and analysis. Driven by 3D coordinate axes derived from joint surface topology, the analyses in Chapter II reveal terrestrial adaptations -- such as a medially oriented hallux (81°), serially shorter phalanges on …

Invertebrate Functional Diversity Of Fossils From Arrow Canyon, Nevada, Nathaniel Valentine

Undergraduate Research Symposium Podium Presentations

Paleontology can be used to study how ecosystems evolve and respond to changes in the environment. Here we examine invertebrate fossils from the Pennsylvanian, a time period that ranged from 323.2 to 298.9 million years ago, which are preserved along the walls of Arrow Canyon (Nevada) in the Bird Spring Formation. We surveyed three sites within the canyon, and used data from the Paleobiology Database to create a list of taxa found on the canyon from this time interval. Although ecosystems have traditionally been studied using the composition of the ecosystem (the number of species), recent work has shown that …

Tooth Type And Position In A Hypothetical Pectinodon..., Keith Snyder, Jonathon Campos, Neal Doran, Charity Simmons

Achieve

In 1856, Leidy rst identied Troodontidae as a taxonomic unit. It was not until 1945 that C.M. Sternberg assigned it to a family status. There has been much debate on taxonomic naming in this family, but in 1987, Currie conated all previous names into a single species, Troodon formosus. On the basis of isolated teeth, Carpenter (1982) suggested a second species, Pectinodon bakkeri from the Lance Formations. With limited specimens (24), Longrich (2008) proposed tooth positioning for the 4 tooth types he dened. This was especially challenging since no cranial or post-cranial skeletal structures have yet been identied.

Over the …

Tales In The Teeth: Using Isotopic Analysis To Understand The Paleoecology And Social Behavior Of Brontotheres Of The Intermountain Basins During The Middle Eocene, John Michael Michalski

All Graduate Reports and Creative Projects, Fall 2023 to Present

Isotopic analysis has been a common practice used in paleontology to study ancient ecosystems, and the lives of animals therein. Oxygen isotopic analysis is of particular importance not only because of its use in studying paleoecology, diet, and migration, but also its use in studying mountain elevation, and its impact on ancient ecosystems. I use stable oxygen isotopic analysis to study the habits and ecology of brontotheres from intermountain basins surrounding the Uinta Mountains of Utah and Wyoming, USA. I studied the oxygen isotopes from 16 fossil specimens of teeth, most of which belonged to brontotheres, including the genera Palaeosyops …

Biostratigraphic Revision Of Esthonyx (Tillidontia, Mammalia) In The Contect Of Climate Change In The Lower Eocene Of The Bighorn Basin, Wyoming, John Colter Johnson

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Esthonyx is an early Eocene tillodont found in North America, Europe, and India. The genus was named by Edward Drinker (E. D.) Cope in 1874 based on specimens from the San Jose Formation in New Mexico. Since then, several species of Esthonyx have been described from North America alone. The best record of Esthonyx comes from the central Bighorn Basin (BHB) in Wyoming, where it appears in 220 localities in a 640 m-thick stratigraphic succession. Since the last summary of Esthonyx in the BHB, several hundred new specimens have been collected and curated at the Denver Museum of Nature and …

Phylogeny And Disparity Of Ammonoid Family Acanthoceratidae Over Ocean Anoxic Event 2, Lindsey Howard

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The widespread use of genera as proxies for species in paleobiological studies might affect the results of these studies. Although most attention has been given to taxonomic diversity studies, this could also be true of disparity and phylogenetic studies. In particular, the assumption that particular character states truly diagnose all members of a genus might distort results. This study examines the disparity of Acanthoceratid ammonoids at both the generic and species level. 149 species from 42 genera were examined with 52 characters measured. Following the measurements, an inverse modeling simulation was run 100 times to generate a simulated phylogeny with …

Painting A New Perspective On Ordovician Echinoderm Diversity Patterns, Ohav Barak Harris

USF Tampa Graduate Theses and Dissertations

The Ordovician Period was a time of great biotic and environmental change, encompassing two important biotic events: the Great Ordovician Biodiversification Event (GOBE) and the Late Ordovician Mass Extinction (LOME). The GOBE occurred during the Middle Ordovician and was a period of rapid diversity increase for marine invertebrate groups, as lower-level taxonomic groups like families and genera came into the forefront. The Ordovician ends with the LOME, an extinction event that is thought to have occurred in two phases: an initial glaciation followed by a subsequent warming. Approximately 85% of marine species went extinct during the LOME, making it the …

Theory Of An Automatic Seepage Meter And Ramifications For Applications, V. A. Zlotnik, D. K. Solomon, D. P. Genereux, T. E. Gilmore, C. E. Humphrey, A. R. Mittelstet, A. V. Zlotnik

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Burning Calories, Burning Ocean: Metabolic Rate In Bivalves As A Predictor Of Extinction Selectivity Through Time And During Rapid Global Warming, Siddharth Gavirneni

Theses - ALL

Organismal metabolic rate is linked to environmental temperature and oxygen consumption, and as such, may be a useful predictor of extinction risk during major climate- driven crises. However, metabolic attributes can be quantified in many ways, highlighting differing aspects of organisms’ ecology. Here, we estimate resting whole-body and mass-specific metabolic rates in post-Carboniferous bivalve taxa using body size and seawater paleotemperature to assess how metabolic rate determines survival both during and outside of intervals of rapid climate warming, or ‘hyperthermals’. Accounting for the effects of geographic range size, we find a pattern of preferential extinction of bivalves with lower total …

Paleoecology Of The Late Cretaceous Western Interior Seaway And Gulf Coastal Plain, Ceara Kathleen Quinn Purcell

Earth and Planetary Sciences ETDs

This dissertation presents research into the paleobiogeography and paleoecology of the Western Interior Seaway (WIS) and Gulf Coastal Plain (GCP) during the Late Cretaceous. The dataset utilized here includes an extensive record of marine invertebrates from over 200 years of fossil collecting and sedimentary data collated from over 45 different literature sources, representing approximately 17 million years of deposition. The high-resolution of this dataset, and its extensive geographic distribution and temporal duration, make it ideal for exploring various ecological questions. Using these data, I have attempted to reconstruct paleobiogeographic provinces as published in prior works, explore functional diversity patterns, and …

Controls On Soft Tissue And Cellular Preservation In Late Eocene And Oligocene Vertebrate Fossils From The White River And Arikaree Groups Of Nebraska, South Dakota, And Wyoming, John E. Gallucci, Grace Woolslayer, Kelsey Barker, Brian Kibelstis, Allison R Tumarkin-Deratzian, Paul V. Ullmann, David E. Grandstaff, Dennis O. Terry

School of Earth & Environment Departmental Research

Previous studies on microtaphonomy have identified multiple types of organic microstructures in fossil vertebrates from a variety of time periods and past environmental settings. This study investigates potential taphonomic, paleoenvironmental, and paleoclimatic controls on soft tissue and cellular preservation in fossil bone. To this end, fifteen vertebrate fossils were studied: eight fossils collected from the Oligocene Sharps Formation of the Arikaree Group in Badlands National Park, South Dakota, and seven fossils from formations in the underlying White River Group, including the Oligocene Brule Formation of Badlands National Park, and the Eocene Chadron Formation of Flagstaff Rim, Wyoming; Toadstool Geologic Park, …

Ecological Dynamics Of Cenozoic North American Mammals, Alexandria Brandis Shupinski

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Understanding how community structure is affected by various ecological, climatic, and environmental changes is a long-standing goal in ecology. However, disentangling human impacts from these other variables is difficult when using short modern timescales and anthropogenically altered communities. The fossil record provides a means to investigate community structure dynamics across critical intervals, excluding humans as a variable. Here, in three studies, I assess changes in North American mammal paleocommunity structure across the last 66 million years (Ma) at multiple temporal and spatial scales. In Chapter 1, I identify changes in mammal functional diversity (FD) locally and continentally, using three independent …