Paleobiology Commons^™

Minerals Rock!: Improving Audience Engagement And Interest In Stem Through Enhancement Of The In-Person And Online Mineral Collection At Ursinus College, Juliette Lyons

Environment and Sustainability Summer Fellows

Museums are a vital source of educational resources for the general public. They provide information on a variety of topics and disciplines and encourage visitors to be excited about and engaged in learning something new. As we work to comprehend key topics such as climate change, it is especially important for the broader public to better understand science, including geology. While the geological collection at Ursinus, Pieces of Earth’s History, is not in a museum, implementing methods that museums use can improve the reception of the collection. Through the application of research gathered through articles, journals, books, and talking with …

A Multi-Isotope Investigation Of Mammoth Diet, Habitat, And Movement Patterns In The Central Great Plains, U.S.A., Jacob Mccloskey

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

During the Last Glacial Maximum (LGM), the Great Plains in Nebraska consisted of wooded parklands and grasslands, whereas spruce (Picea) forests, parklands, and steppe grasslands dominated east of the Missouri River. I analyzed bulk carbon (δ¹³C), oxygen (δ¹⁸O), and strontium (⁸⁷Sr/⁸⁶Sr) isotopes from tooth enamel in isolated mammoth (Mammuthus) molars to compare diet and movement patterns in two late Pleistocene assemblages: one in Nebraska (n = 24), and one in western Iowa and Missouri (n = 17). Furthermore, I identified a morphometric subset of molars as …

The Petm: A Window Into Earth's Future Climate, Jacalyn M. Wittmer Malinowski

Climate Change and the Individual, 2025-26

The Paleocene-Eocene Thermal Maximum (PETM) is not just an event that occurred in Earth’s distant past (~55 million years ago) but is a crucial lesson for today’s meteoric climate change. The PETM offers a historical parallel of rapid flux of greenhouse gases into the atmosphere that caused global warming, ocean acidification, dramatic changes in weather, and extinctions. This global warming event was the result of 20,000 years of “rapid” warming (in geological terms) however, we are experiencing rates of warming that are 5-10x higher than PETM levels. We are not experiencing rapid warming today, in comparison to the past, we …

Sedimentary Archives Of Late Quaternary Limnological, Ecological, And Environmental Change In The Eastern Sierra Nevada (California, Usa), Bailee Hodelka

Theses and Dissertations--Earth and Environmental Sciences

The Sierra Nevada essentially serve as the headwaters of California, providing crucial freshwater to the state through seasonal snowmelt. This water supply is threatened by climate change in complex ways that are not fully understood. Geological records provide a valuable source of information on how the hydrology, limnology, and ecology of the Sierra Nevada region has responded to climate changes of the past. This dissertation presents new sedimentary and paleoecological research from Mono Lake and Convict Lake (Mono County, California) and aims to shed light on environmental changes in the eastern Sierra Nevada from ~16 ka to present.

At Mono …

Evaluating Fungal Population Response To The Miocene Climatic Optimum: High-Resolution Palynological Insights From The South China Sea And Mcmurdo Sound, Antarctica, Mallory Pilie

LSU Master's Theses

Fungi play key and specific roles in ecosystems, specifically as many have restricted geographic distributions, known host/substrate preferences, and are important local environmental indicators due to their short dispersal distances. This study of fossil fungi from a time interval of pronounced global warming, the Miocene Climatic Optimum (MCO), allows analysis of fungal response to an analogue for future climate change scenarios. The research presented herein is part of a larger project, Fungi in a Warmer World (FiaWW), which is using globally-distributed sediment samples to provide foundational information on fungal community distribution patterns and will provide the first fungi-based climatological reconstructions …

Palynology And Paleoclimatology Of The Chicxulub Impact Crater In The Early Paleogene, Vann Smith

LSU Doctoral Dissertations

At the end of the Cretaceous Period, a large bolide impacted the Earth and formed the Chicxulub impact crater in the Yucatán Peninsula, Mexico. In 2016, International Ocean Discovery Program (IODP) Expedition 364 Site M0077 drilled into the buried peak ring of the crater, recovering a marine Paleocene to early Eocene post-impact section deposited on top of the impact breccia. Palynological analysis of 195 samples from the post-impact section has yielded the first pre-Holocene vegetational record from inside the Chicxulub impact crater and the first palynological record of the recovery of life following the end-Cretaceous mass extinction from inside the …

Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey, Corinne Myers, Jason Moore, Louis Scuderi

Earth and Planetary Sciences ETDs

Multiple linear regression was used to determine the relationships between diversity-independent factors (i.e., abiotic, climatic) 2, 5, and 10 Myrs-prior to the most elevated Phanerozoic extinctions. We constructed five abiotic variables from Phanerozoic proxy records1–5 to compare to extinction rates: mean temperature, temperature instability, carbon cycle instability, continental weathering rates, and habitat instability. All three models were statistically significant (P < 0.05) and explained > 70% of the variation in Alroy’s6 three-timer generic extinction rates. However, the 2 Myr-prior model explained the most variance in extinction rates and had the most predictive power, based on adjusted and predictive R2 (~ 72% and 41%, respectively). Carbon …

Diversity – Independent Factors Predict Elevated Extinction Rates, Dustin Perriguey

Earth and Planetary Sciences Faculty and Staff Publications

Multiple linear regression was used to determine the relationships between diversity-independent factors (i.e., abiotic, climatic) 2, 5, and 10 Myrs-prior to the most elevated Phanerozoic extinctions. We constructed five abiotic variables from Phanerozoic proxy records1–5 to compare to extinction rates: mean temperature, temperature instability, carbon cycle instability, continental weathering rates, and habitat instability. All three models were statistically significant (P < 0.05) and explained > 70% of the variation in Alroy’s6 three-timer generic extinction rates. However, the 2 Myr-prior model explained the most variance in extinction rates and had the most predictive power, based on adjusted and predictive R2 (~ 72% and 41%, respectively). Carbon …

Improving Thorium-230 Determination In Marine Sediment, Katherine Mateos

Independent Study Project (ISP) Collection

Our oceans are intimately related to the climate of our planet. Paleoceanographic approaches aim to study oceans through geologic time to improve models of future climate. Radioisotopes provide us with chemical tracers that help us understand change through time. The uraniumseries decay chain contains thorium-230, a decay product of uranium-234. This isotope is useful to paleoceanographers in its disequilibrium to its parent isotope and in determining the flux of sediment falling to the ocean floor. In order to use 230Th to study oceans, we must be able to accurately measure the amount of thorium in sediment samples. Thorium is found …

Assessing Diagenetic Conditions In The Late Triassic Chinle Formation Through Petrographic And Geochemical Analysis Of Phytosaur Teeth, John Fortner

Earth Sciences Theses and Dissertations

The Upper Triassic (Norian; ~227-208 Ma) Chinle Formation of Petrified Forest (PeFo) National Park was deposited during a time of major tectonic breakup and profound changes in atmospheric circulation and faunal compositions. Little has been done however to assess whether surficial paleoenvironmental trends related to deterioration of the Late Triassic Megamonsoon resulted in similar trends in the early diagenetic environment. Here, we use phytosaur tooth dentin as a proxy for diagenetic conditions in the Chinle of PEFO, as its greater susceptibility to chemical alteration relative to enamel makes it an excellent substrate from which changing diagenetic conditions may be studied …

Constraining The Oxygen Values Of The Late Cretaceous Western Interior Seaway Using Marine Bivalves, Camille H. Dwyer

Earth and Planetary Sciences ETDs

The Western Interior Seaway (WIS) remains an oceanographic enigma, including its circulation, similarity to the open ocean, and the fidelity of geochemical proxies to reconstruct paleoenvironments. Across the late Campanian and early Maastrichtian I test whether: 1) the WIS had unique δ¹⁸O_VPDB compared to other marine settings, 2) increasing oceanographic restriction changed the stable isotope composition, and 3) biases, e.g., taxonomy or diagenesis, influenced stable isotope compositions. Results indicate distinct δ¹⁸O_VPDB in the WIS compared to other marine settings. δ¹⁸O_VPDB values were stable through time, suggesting insignificant oceanographic restriction and a …

Giant Beaver Palaeoecology Inferred From Stable Isotopes, Tessa Plint, Fred J. Longstaffe, Grant Zazula

Earth Sciences Publications

This is a multi-individual (n = 11), stable carbon and nitrogen isotope study of bone collagen (δ¹³C_col and δ¹⁵N_col) from the giant beaver (genus Castoroides). The now-extinct giant beaver was once one of the most widespread Pleistocene megafauna in North America. We confirm that Castoroides consumed a diet of predominantly submerged aquatic macrophytes. These dietary preferences rendered the giant beaver highly dependent on wetland habitat for survival. Castoroides’ δ¹³C_col and δ¹⁵N_col do not support the hypothesis that the giant beaver consumed trees or woody …

Reframing The Mammoth Steppe: Insights From Analysis Of Isotopic Niches, Rachel Schwartz-Narbonne, Fred J. Longstaffe, Kevin J. Karydynal, Patrick Druckenmiller, Keith A. Hobson, Christopher N. Jass, Jessica Z. Metcalfe, Grant Zazula

Earth Sciences Publications

Woolly mammoth (Mammuthus primigenius), horse (Equus spp.) and bison (Bisonspp.) coexisted with a variety of mammalian megafauna across the Pleistocene mammoth steppe e a megacontinental ecosystem that spanned northern Eurasia and northwestern North America. Previous research has suggested that highly conserved niches with minimal niche overlap allowed high levels of species diversity on the mammoth steppe. Here we evaluate previously published and some new collagen carbon and nitrogen isotope data (delta¹³C, delta¹⁵N) for mammoth steppe megaherbivores using Stable Isotope Bayesian Ellipses in R (SIBER) and linear regression models to determine isotopic …

Stable Isotopic Characterization Of A Coastal Floodplain Forest Community: A Case Study For Isotopic Reconstruction Of Mesozoic Vertebrate Assemblages, Thomas M. Cullen, Fred Longstaffe, Ulrich G. Wortmann, Mark B. Goodwin, Li Huang, David C. Evans

Earth Sciences Publications

Stable isotopes are powerful tools for elucidating ecological trends in extant vertebrate communities, though their application to Mesozoic ecosystems is complicated by a lack of extant isotope data from comparable environments/ecosystems (e.g. coastal floodplain forest environments, lacking significant C₄ plant components). We sampled 20 taxa across a broad phylogenetic, body size, and physiological scope from the Atchafalaya River Basin of Louisiana as an environmental analogue to the Late Cretaceous coastal floodplains of North America. Samples were analysed for stable carbon, oxygen and nitrogen isotope compositions from bioapatite and keratin tissues to test the degree of ecological resolution that can …

Biodiversity And Distribution Of Benthic Foraminifera In Harrington Sound, Bermuda: The Effects Of Physical And Geochemical Factors On Dominant Taxa, Nam Le

Honors Theses

Harrington Sound, Bermuda, is a nearly enclosed lagoon acting as a subtropical/tropical, carbonate-rich basin in which carbonate sediments, reef patches, and carbonate-producing organisms accumulate. Here, one of the most important calcareous groups is the Foraminifera. Analyses of common benthic orders, including miliolids (Quinqueloculina and Triloculina spp.) and rotaliids (Homotrema rubrum, Elphidium spp., and Ammonia beccarii), are essential in understanding past and present environmental conditions affecting the island's coastal environment. These taxa have been studied previously; however, factors explaining their individual patterns of abundance in the Sound are not well detailed. The goal of this study is …

Evaluating Stable Isotope And Geochronologic Techniques For Paleoclimate Reconstruction: Case Study Of The Santa Cruz Formation, Argentina, Robin B. Trayler

Boise State University Theses and Dissertations

Stable isotope analysis has become the method of choice for many studies investigating the paleoecology and paleoclimate of fossil mammal faunas. While organic tissues (collagen, keratins, proteins) persist for < 10⁵ years highly mineralized tooth enamel is resistant to alteration and degradation and faithfully preserves its isotopic composition for millions (> 10⁶) years. Reconstructing past climates from these records relies on both understanding both micro-scale mechanisms of isotope incorporation into individual teeth, and macro-scale changes in isotope compositions over hundreds of thousands or millions of years. In this dissertation I address three questions.

First, how does the geometry and …

Are The Oxygen Isotope Values Of The Late Cretaceous Western Interior Seaway Different From The Open Ocean?, Camille H. Dwyer, Corinne Myers, Viorel Atudorei

Shared Knowledge Conference

The Western Interior Seaway (WIS) was a North American epicontinental sea that was connected to the open ocean through the passage of the northern Boreal Sea and the southern Tethys Sea from the early Albian (~113 million years ago) to the early Paleogene (~65 million years ago). The WIS began to recced and lost its connection to the southern Tethys Sea in the late Campanian (~72 million years ago). In the early Paleogene, the WIS dried up completely. The oxygen isotopic composition (δ18O) of benthic bivalves was measured from the upper Campanian and lower Maastrichtian (75 million years ago to …

Cretaceous Dinosaurs And The World They Lived In: A New Species Of Ornithischian Dinosaur From The Early Cretaceous (Aptian) Of Texas, Reconstruction Of The Brain Endocast And Inner Ear Of Malawisaurus Dixeyi, And Reconstruction Of The Paleoclimate And Paleoenvironment Of Cretaceous Terrestrial Formations In Texas And Oklahoma Using Pedogenic Minerals, Kate Andrzejewski

Earth Sciences Theses and Dissertations

Material from over thirty individuals of a new ornithopod was recovered from the Proctor Lake locality in the Twin Mountains Formation (Aptian) of north-central Texas. This material includes various ontogenetic stages, providing insight into the growth patterns of this species. The new ornithopod is recovered basal to Iguanodontia, but more derived than Hypsilophodon foxii. The presence and morphology of 4 premaxillary teeth along with a combination of both basal and derived characters distinguish this taxon from all other ornithopods.

A braincase of the Cretaceous titanosaurian sauropod Malawisaurus dixeyi was CT scanned and a 3D rendering of the endocast and inner …

Nitrogen Isotopes Suggest A Change In Nitrogen Dynamics Between The Late Pleistocene And Modern Time In Yukon, Canada, Farnoush Tahmasebi, Fred J. Longstaffe, Grant Zazula

Earth Sciences Publications

A magnificent repository of Late Pleistocene terrestrial megafauna fossils is contained in ice-rich loess deposits of Alaska and Yukon, collectively eastern Beringia. The stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope compositions of bone collagen from these fossils are routinely used to determine paleodiet and reconstruct the paleoecosystem. This approach requires consideration of changes in C- and N-isotope dynamics over time and their effects on the terrestrial vegetation isotopic baseline. To test for such changes between the Late Pleistocene and modern time, we compared δ¹³C and δ¹⁵N for vegetation and bone …

Belowground Rhizomes In Paleosols: The Hidden Half Of An Early Devonian Vascular Plant, Jinzhuang Xue, Zhenzhen Deng, Pu Huang, Kangjun Huang, Michael J. Benton, Ying Cui

Dartmouth Scholarship

The colonization of terrestrial environments by rooted vascular plants had far-reaching impacts on the Earth system. However, the belowground structures of early vascular plants are rarely documented, and thus the plant−soil interactions in early terrestrial ecosystems are poorly understood. Here we report the earliest rooted paleosols (fossil soils) in Asia from Early Devonian deposits of Yunnan, China. Plant traces are extensive within the soil and occur as complex network-like structures, which are interpreted as representing long-lived, belowground rhizomes of the basal lycopsid Drepanophycus. The rhizomes produced large clones and helped the plant survive frequent sediment burial in well-drained soils …

Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres

Electronic Theses and Dissertations

Cone in cone concretions found in the Stanley Group of Southeastern Oklahoma have a variety of external and internal attributes which allow diagenetic and theoretical models of formation to be hypothesized. Stanley Group carbonate cone in cone concretions are initially formed in sulfur reducing horizons at shallow burial depths in a poorly circulated possibly deep trough containing siliceous sediments and organic matter. Collected concretions near the town of Smithville, Oklahoma displayed four different external morphologies and four variations of mineral constituents. All concretions contained microscopic cones which initiated diffusion and/or fluid patterns and is an early cementation process that directly …

The Stratigraphic Position Of Fossil Vertebrates From The Pojoaque Member Of The Tesuque Formation (Middle Miocene, Late Barstovian) Near Española, New Mexico, Garrett R. Williamson

Electronic Theses and Dissertations

The stratigraphy of the Pojoaque Member of the Tesuque Formation near Española, NM is not well understood. This region, during the Middle Miocene, represented a dynamic alluvial fan-fluvial-lacustrine environment within the Española Basin while the Rio Grande Rift was active. Cavazza (1986) identified two paleodrainage systems (lithosome A, basin-margin facies and B, basin-floor facies) by means of sandstone and conglomerate petrology, paleocurrent, and sedimentary facies analyses. After x-ray diffraction analyses of claystones within lithosome B, mordenite was discovered, which is a zeolite mineral commonly found within volcanic rocks. This is significant because the presence of mordenite confirms Cavazza’s (1986) conclusion …

The Rise Of Fire: Fossil Charcoal In Late Devonian Marine Shales As An Indicator Of Expanding Terrestrial Ecosystems, Fire, And Atmospheric Change, Susan M. Rimmer, Sarah J. Hawkins, Andrew C. Scott, Walter L. Cressler Iii

Earth & Space Sciences Faculty Publications

No abstract provided.

Ice Caves On Extraterrestrial Bodies: What Are The Prospects For Speleogenesis And Detection?, Penelope J. Boston

The International Workshop on Ice Caves

Potential mechanisms for creating cavities in icy extraterrestrial bodies have been tentatively explored by several authors. On one hand we have examples of mechanisms that create caves in water ice here on Earth. In addition, there may be unique mechanisms on other Solar System objects that do not occur on Earth but might produce cavities, e.g. sublimation of comets upon perihelion passage. The methods of detecting such cavities depend upon the nature of the icy body in question, the potential for orbital or landed missions to visit those bodies in the future, and remote or landed methods for detecting the …

The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, Anne-Lise Ducluzeau, Barbara Schoepp-Cothenet, Robert Van Lis, Frauke Baymann, Michael J. Russell, Wilfgang Nitschke

Department of Biochemistry: Faculty Publications

Complex life on our planet crucially depends on strong redox disequilibria afforded by the almost ubiquitous presence of highly oxidizing molecular oxygen. However, the history of O₂-levels in the atmosphere is complex and prior to the Great Oxidation Event some 2.3 billion years ago, the amount of O₂ in the biosphere is considered to have been extremely low as compared with present-day values. Therefore the evolutionary histories of life and of O₂-levels are likely intricately intertwined. The obvious biological proxy for inferring the impact of changing O₂-levels on life is the evolutionary history …

Upper Pleistocene And Holocene Palaeoenvironmental Records In Cueva Mayor Karst (Atapuerca, Spain) From Different Proxies: Speleothem Crystal Fabrics, Palynology And Archaeology., Virginia Martínez-Pillado, Arantza Aranburu, Juan Luis Arsuaga, Blanca Ruiz-Zapata, Maria José Gil-García, Heather Stoll, Iñaki Yusta, Eneko Iriarte, José Miguel Carretero, R. Lawrence Edwards, Hai Cheng

International Journal of Speleology

The Cueva Mayor karst system of Atapuerca, in Northern Spain, hosts a highly significant record of human occupation from the Pleistocene. The climatic context of the human activities during the Pleistocene-Holocene for this inland site has not been well constrained, since existing records of the palaeoclimatic evolution of the Northern Iberian Peninsula are from more distal coastal and high-elevation sites. In this study, we interpret the palaeoenvironmental information recorded on the petrography of a stalagmite and the pollen spectra of the Sierra de Atapuerca karst system during the last 20 kyr. The integration of both types of records has allowed …

Cyclic Distributional Model Of The Late Moscovian Fusulinids In The Donets Basin (Ukraine) In Response To Eustatic Sea Level Fluctuations And Its Application In Biostratigraphy And Correlation, Rimma Khodjanyazova

Boise State University Theses and Dissertations

The continuous Pennsylvanian shallow-marine, paralic, siliciclastic succession in the Donets Basin is pivotal for correlation of marine and continental strata in northern Pangaea with coeval shallow-marine mainly carbonate strata in the Moscow Basin, a historical type area of Moscovian Horizons. The details of the history of establishment, lithostratigraphy and current biostratigraphy of Podolskian and Myachkovian Horizons in the Moscow Basin that are not readily available in Western literature are reviewed.

A model of cyclic recurrence (~0.6 —1myr) of three main fusulinid assemblages in the Pennsylvanian siliciclastic-carbonate succession in the Donets Basin is proposed. A Hemifusulina-association (A) indicates the onset …

Paleoecology Of Nebraska’S Ungulates During The Eocene–Oligocene Climate Transition, Grant S. Boardman

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

The White River Group (WRG) preserves the Eocene-Oligocene climate transition (EOCT), an interval of global cooling and drying during the onset of Antarctic glaciation. In the Great Plains, a shift from forested conditions to drier woodland-savanna biomes is hypothesized to have occurred at this time. I test this hypothesis through the analyses of several paleoenvironmental proxies on the teeth of 12 WRG ungulate species: stable carbon and oxygen isotopes from tooth enamel, and mesowear and microwear texture. The EOCT shift toward more open habitats and lower vegetation density under drying climates should have resulted in an increase in mean carbon …

Chemostratigraphy Of The Early Pliocene Diatomite Interval From Mis And-1b Core (Antarctica): Paleoenvironment Implications, Giovanna Scopelliti, Adriana Bellanca, Donata Monien, Gerhard Kuhn

ANDRILL Research and Publications

The AND-1B drill core (1285 m-long) was recovered, inside the ANDRILL (ANtarctic geological DRILLing) Program, during the austral summer of 2006/07 from beneath the floating McMurdo Ice Shelf. Drilling recovered a stratigraphic succession of alternating diamictites, diatomites and volcaniclastic sediments spanning about the last 14 Ma. A core portion between 350 and 480 mbsf, including a 80 m-thick diatomite interval recording the early Pliocene warming event, was investigated in term of opal biogenic content and element geochemistry. Across the diatomite interval, in spite of the lithological uniformity, a fluctuating biogenic opal profile mirrors the δ18O record, testifying a decrease in …

Geochemical Analysis Of Cenozoic Fossil Conifers At High Latitudes: Implications For Molecular Preservation And Environmental Change, Caitlyn Witkowski

Honors Projects in Science and Technology

Fossil materials record ancient life and their adapted environment. Arctic plant fossils are critical for our understanding of the Earth’s paleoenvironment when high latitudes were under ice-free conditions. All Arctic plant fossils in this research are conifers, plants conducive for morphological and molecular study because of their incredible genetic stability. Miocene (15 million year old) and Pliocene (5 million year old) conifer leaves were collected from Banks Island, Canada (Williams et al., 2008). Samples were analyzed and compared with Paleocene (60 million year old) and Eocene (45 million year old) samples from Axel Heiberg Island, Canada and with modern equivalent …