Ecology and Evolutionary Biology Commons^™

Ediacaran Paleocommunity Structure, Body Size Evolution, And The Rise Of Complex Animals, Matthew Philip Craffey

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

The Ediacaran period (635-538ma) is a key interval in the evolution of life as it records the first macroscopic animal communities. Major extinction pulses appear to have altered the composition of the global marine biosphere between each sub-interval of the Ediacaran Period: the Avalon, White Sea, and Nama assemblage Zones. While considerable attention has been paid to the causes of these extinction pulses, less has been afforded to the consequences of Ediacaran biotic turnover for community organization and function. Moreover, it is unclear how body size - the defining trait of macrofauna - affected the transition between animal groups across …

Spatial Ecology And Predator–Prey Interactions Of Mountain Lions In California's San Francisco North Bay, Jacob A. Harvey

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding spatial ecology and predator-prey interactions are central to wildlife ecology and conservation. We tracked mountain lions with GPS telemetry to evaluate space use, predator-prey interactions, and resource selection in California’s San Francisco North Bay, USA. In Chapter 1, we evaluated the influence of human disturbance on home range size, prey composition, and kill rates on black-tailed deer (Odocoileus hemionus columbianus) across an urban-rural gradient. Both males and females increased home range size with increasing development at low to moderate levels of development, but female home range size stabilized across greater proportions of development while male home range …

Maggot Mass Effect On The Development And Survival Of Forensic Blow Flies, Akomavo Fabrice Gbenonsi

School of Natural Resources: Dissertations, Theses, and Student Research

Forensic entomology scientists use blow flies' developing patterns to estimate the postmortem interval (PMI). However, larval aggregations produce metabolic heat, resulting in complex microclimates that may change growth timetables. This study investigates how larval density and associated temperature changes affect the development and survival of two forensically essential blow fly species, Lucilia sericata and Calliphora vicina.

This study examined how larval density and associated thermal profiles affect the development of both blow fly species. Using a split-plot design, we tested four larval densities at 25°C and 30°C, with temperature gradients measured via thermocouple at four mass positions three times …

Pastoral Land Condition: Kimberley Land Condition Standards, Robert Sudmeyer, Rick Fletcher, Kathryn Ryan, Matthew Fletcher, Charles Martin, Philip Thomas, Karen Holmes, Karyn Reeves, Wayne Fletcher

Natural resources published reports

This report outlines the conceptual basis and quantitative land condition standards that define acceptable pastoral land condition for the Kimberley, Western Australia (WA), to meet the regulatory requirements of the Land Administration Act 1997 and the Soil and Land Conservation Act 1945.

The Department of Primary Industries and Regional Development (DPIRD) develops regional-level pastoral land condition standards for WA to implement the Framework for sustainable pastoral management – Revised edition, which is designed to address the Office of the Auditor General’s recommendations to improve the management of pastoral lands in WA. The application of these standards is expected to …

Walleye And Sauger Movement And Entrainment In Lewis And Clark Lake, William Joseph Radigan

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

Walleye Sander vitreus and Sauger Sander canadensis are both socioeconomically important sportfish species in Lewis and Clark Lake, an interjurisdictionally managed mainstem Missouri River reservoir fishery. Since 2011, adult catch per unit effort (CPUE) of both Walleye and Sauger has remained at approximately 50% of pre-2011 levels. A presumed reason for the suppressed CPUE of adult Walleye and Sauger is substantial entrainment of larval and adult fish resulting from the reservoir’s high turnover rate (7.2 d). Acoustic telemetry was used to quantify adult movement and entrainment and ichthyoplankton trawls were used to assess larval entrainment. Relative importance of factors driving …

Landscape Effects On The Beneficial Arthropod Community In Agriculturally Dominated Environments, Hannah E. Stowe

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

Ecosystem services in agriculturally dominated regions rely, at least in part, on arthropods. Environment and biodiversity influence beneficial arthropods in population size, community structure, diversity, and ecosystem service provisioning. Predation is among the most important services provided by arthropods in agroecosystems. Understanding what alters predation and predator activity can support the successful application of biological control and, more broadly, integrated pest management. Land use and edge adjacency, field characteristics, landscape, seasonality, and diel period all alter predatory behavior. Crop fields dominate Nebraska agroecosystems, although interspersed perennial grasslands persist through the Conservation Reserve Program (CRP). Such grasslands supply crucial resources and …

Latitudinal Gradients In Arctic Willows And Their Effects On Stream-Riparian Systems, Donal Heaney

Honors Scholar Theses

Extreme warming in the Arctic due to climate change presents the opportunity to study rapid changes to ecosystems and their potential resilience. Willow (Salix) shrubs form the base of many Arctic riparian ecosystems, and they have increased in height and range as temperatures have warmed. The effects of warming on willows could alter riparian ecosystems and neighboring streams, so understanding how climate change will affect willows is integral to understanding how the stream-riparian meta-ecosystem might change. I used data from the EvoME Institute to compare willow canopy cover above Arctic streams along a latitudinal transect and investigate how …

Ghosts In Glass: Ghost Crabs As Judges Of Glass Sand For Coastal Restoration, Emily Parrish

Honors Theses

Over 60% of the Gulf of Mexico coastline is actively eroding, which has resulted in thousands of miles of lost coastline over the last 100 years. This drastic loss of coastal land highlights the dire need for coastal restoration across the entirety of the Gulf Coast. A vital aspect of restoring these eroded areas is replenishing eroded substrate, traditionally conducted through offshore dredging of substrates which comes with high economic and ecological costs. Recycled glass sand may be able to fill this role and reduce our reliance on dredging while lowering the amount of glass waste entering landfills each year. …

From Land To Lagoon: The Spatiotemporal Biogeochemical Dynamics Of Arctic Coastal Erosion In Elson Lagoon, Alaska, Sasha Victoria Peterson

Open Access Theses & Dissertations

TThe Arctic is warming rapidly, driving widespread environmental change across coastal landscapes, including permafrost thaw, shoreline erosion, and shifts in sediment and carbon dynamics, pose growing challenges for predicting carbon cycling and climate feedbacks. This dissertation investigates the spatiotemporal variability of erosion, decomposition, and nearshore turbidity in Elson Lagoon, Alaska (1955–2023), to better understand how carbon, nitrogen, and sediment are mobilized, transformed, and potentially emitted as greenhouse gases in Arctic coastal systems. Chapter 2 presents a high-resolution analysis of shoreline change and erosion-driven material fluxes spanning nearly seven decades. Drawing on 795 soil data points, airborne LiDAR, and five shoreline …

Primates From Senèze, Eric Delson

Publications and Research

Senèze has yielded two primate fossils, neither from the recent field work. A partial ulna can be identified as cf. Macaca sylvanus. A nearly complete female skull is the holotype of Dolichopithecus arvernensis Depéret, 1928, now included in Paradolichopithecus. Emended and differential diagnoses are provided for this genus and species for the first time, and the Senèze skull is described and briefly compared to those of other species of the genus. Dental and cranial measurements are provided, along with comparative data. The macaque and Paradolichopithecus are moderately to highly terrestrial, respectively, and they suggest a woodland to more open …

How The Biotic And Abiotic Factors In The Belle Forest Cave And Arboretum Soil Dictates Tree Species Prevalence, Amya A. Bingham

SPARK Symposium Presentations

A plethora of factors in the soil impact a plant’s health, including the presence of different biotic and abiotic factors. These include things like temperature, elevation, pH, microbial respiration and the presence of water, clay, loam, silt, sand, nitrogen, potassium, and phosphorus. Different soils will have varying amounts of these, which may dictate what is able to grow in them, and therefore also the surrounding area. This research project explores how the aforementioned biotic and abiotic factors affect the soil at the Belle Forest Cave and Arboretum. Three samples will be taken from four spots along a transect at this …

Transcriptional Profiles Reveal Physiological Mechanisms For Compensation During A Simulated Marine Heatwave In Yellowtail Kingfish (Seriola Lalandi), Sharon E. Hook, Ryan J. Farr, Jenny Su, Alistair J. Hobday, Catherine Wingate, Lindsey Woolley, Luke Pilmer

Fisheries Research Articles

Background

Changing ocean temperatures are already causing declines in populations of marine organisms. Predicting the capacity of organisms to adjust to the pressures posed by climate change is a topic of much current research effort, particularly for species we farm or harvest. To explore one measure of phenotypic plasticity, the physiological compensations in response to heat stress as might be experienced in a marine heatwave, we exposed Yellowtail Kingfish (Seriola lalandi) to sublethal heat stress, and used the transcriptome in gill and muscle, benchmarked against heat shock proteins and oxidative stress indicators, to characterise the acute heat stress …

Using Stable Isotope Analysis To Investigate The Trophic Ecology Of Aquatic Insects, Shelby Ann Medlock

Master's Theses

Despite their abundance on the landscape, ponds and associated macroinvertebrate assemblages have largely been underrepresented in scientific studies, which usually focus on lakes or streams. Similar to other waterbodies, ponds can harbor high levels of invertebrate biodiversity, which is important as aquatic insects are experiencing declines due to habitat destruction, pollution, climate change, and invasive species introductions. To evaluate how these threats impact pond insects and the ecosystem services they may provide, a thorough understanding of their ecology is essential. However, significant knowledge gaps remain, especially regarding trophic levels and species-specific diets. To address these knowledge gaps, I used carbon …

Variation In Thermal Tolerance Plasticity And The Costs Of Heat Exposure In The Estuarine Sea Hare, Phyllaplysia Taylori, Richelle L. Tanner, Rauri C. K. Bowie, Cynthia Y. Wang-Claypool, Jonathan H. Stillman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Climate change is increasing average temperatures and the frequency and intensity of thermal extremes in coastal marine environments. Organisms in coastal marine habitats are accustomed to environmental fluctuations and possess physiological plasticity that may be advantageous in response to increased occurrence of extremes. To examine whether such plasticity is locally adapted to environmental conditions, we investigated the relationship between genetic diversity and thermal tolerance plasticity in 11 populations of the direct-developing intertidal sea hare, Phyllaplysia taylori, on the western coast of the United States. Using whole-organism metrics of muscle function and metabolic rate and a ddRADseq genomic approach, we …

Reviews And Syntheses: Variable Inundation Across Earth’S Terrestrial Ecosystems, James Stegen, Amy J. Burgin, Michelle H. Busch, Joshua B. Fisher, Joshua Ladau, Jenna Abrahamson, Lauren Kinsman-Costello, Li Li, Xingyuan Chen, Thibault Datry, Nate Mcdowell, Corianne Tatariw, Anna Braswell, Jillian M. Deines, Julia A. Guimond, Peter Regler, Kenton Rod, Edward K. P. Bam, Etienne Fluet-Chouinard, Inke Forbrich, Kristin L. Jaeger, Teri O'Meara, Tim Scheibe, Erin Seybold, Jon N. Sweetman, Jianqiu Zheng, Daniel C. Allen, Elizabeth Herndon, Beth A. Middleton, Scott Painter, Kevin Roche, Julianne Scamardo, Ross Vander Vorste, Kristin Boye, Ellen Wohl, Margaret Zimmer, Kelly Hondula, Maggi Laan, Anna Marshall, Kaizad F. Patel

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The structure, function, and dynamics of Earth's terrestrial ecosystems are profoundly influenced by how often (frequency) and how long (duration) they are inundated with water. A diverse array of natural and human-engineered systems experience temporally variable inundation whereby they fluctuate between inundated and non-inundated states. Variable inundation spans extreme events to predictable sub-daily cycles. Variably inundated ecosystems (VIEs) include hillslopes, non-perennial streams, wetlands, floodplains, temporary ponds, tidal systems, storm-impacted coastal zones, and human-engineered systems. VIEs are diverse in terms of inundation regimes, water chemistry and flow velocity, soil and sediment properties, vegetation, and many other properties. The spatial and temporal …

Бадхызские Архивы. Том 2, Р. И. Горелова, В. Я. Фет

Open Access Books

Gorelova, RI, Fet V, editors. The Badkhyz Archives, Vol. 2. Huntington, WV: Marshall University Libraries; 2025. 387 p.

This book represents the second volume of the series started in 2021. It compiles memoirs and research information about the unique Badkhyz Natural Reserve, now in Turkmenistan, formerly at the southernmost point of the USSR. Established in 1941, the Reserve—nicknamed a Serengeti of Central Asia— housed many unique and endangered species, with an iconic wild ass, or kulan, preserved only there. The second volume includes unique and otherwise unavailable information about the workers of the Reserve in 1940s-1980s. We continuento publish …

Quantified Lives: Data, Bias, And The Cost Of Categorization, Colin F. Geraghty

Dissertations, Theses, and Capstone Projects

This project critically examines how statistical methods and data visualization have historically been used to categorize, rank, and control human populations. By exploring the works of key figures like Francis Galton, Karl Pearson, and R.A. Fisher, it traces the evolution of categorization frameworks from their eugenic roots to modern applications in artificial intelligence and global metrics like the World Happiness Report. Through interactive visualizations and historical analysis, the project invites users to question the legitimacy of these frameworks and reflect on their impact on society. At its core, this work emphasizes the need to move beyond rigid classification systems, challenging …

Climate Influence On Both Spatial And Temporal Patterns Of Rocky Intertidal Community Structure In San Diego, California, Emily Jenkins

Theses

The rocky intertidal ecosystem, the coastal area between high and low tides, serves as a critical buffer between land and sea. This ecosystem supports a diverse array of species and provides rich opportunities for exploration and education. With the influence of climate change, this ecosystem faces significant shifts in species distribution, resilience and recovery from environmental disturbances, as well as habitat loss (Jackson & McIlvenny 2011; Jueterbock et al. 2013; Menge & Gravem 2022; Rilov et al. 2021; Sagarin & Barry 1999). Between 2014-2016, climate anomalies El Niño (ENSO) and the Pacific Decadal Oscillation (PDO) combined to create a period …

Scaling Arctic Landscape And Permafrost Features Improves Active Layer Depth Modeling, Wouter Hantson, Daryl Yang, Shawn P. Serbin, Joshua B. Fisher, Daniel J. Hayes

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tundra ecosystems in the Arctic store up to 40% of global below-ground organic carbon but are exposed to the fastest climate warming on Earth. However, accurately monitoring landscape changes in the Arctic is challenging due to the complex interactions among permafrost, micro-topography, climate, vegetation, and disturbance. This complexity results in high spatiotemporal variability in permafrost distribution and active layer depth (ALD). Moreover, these key tundra processes interact at different scales, and an observational mismatch can limit our understanding of intrinsic connections and dynamics between above and below-ground processes. Consequently, this could limit our ability to model and anticipate how ALD …

On Solving Differential Equations Describing The Ecology Of Shallow Lakes: A Comparison Of Classical And Modern Computational Methods Through Python, Vruddhi Kapre, Jeffrey R. Anderson, Alessandro Maria Selvitella

Spora: A Journal of Biomathematics

In this exposition paper, we describe some computational methodologies to solve numerically differential equations modeling the shallow lake ecosystem, with particular focus on the dynamics of the phosphorus. We describe in detail Python implementations of classical algorithms, like Runge-Kutta, and more modern approaches, including physics-informed neural networks.

Reproductive Costs In Female, Island-Dwelling Eastern Diamondback Rattlesnakes (Crotalus Adamanteus), Emily R. Gray

Theses, Dissertations and Capstones

Eastern Diamondback Rattlesnakes (Crotalus adamanteus; EDBs) are a declining species endemic to the Southeastern Coastal Plain. Reproduction is costly for females, which are ovoviviparous, slow to mature, reproduce infrequently, and are often emaciated after parturition. Yet, we have a limited understanding of the trade-offs associated with their reproductive biology. Thus, I had three objectives: 1) assess reproduction-associated water stress and determine how female EDBs respond to altered water budgets in situ (Chapter 1), 2) evaluate the interactive effects of body condition and rainfall on female hydration, with a special focus on musculature as a condition index (Chapter 1), …

Investigating Drivers In Phytoplankton Between Lentic And Lotic Ecosystems Within Twelvepole Creek Watershed, Devin Lee Farmer

Theses, Dissertations and Capstones

Harmful Algal Blooms (HABs) threaten aquatic ecosystems, local economies, and water quality. While extensively studied in lakes (lentic systems), their impact on flowing waters (lotic systems) remains underexplored. This study examined algal drivers in both ecosystems within the same watershed, focusing on Beech Fork Lake (lentic) and Twelve Pole Creek (lotic). Key environmental factors, including pH, turbidity, dissolved oxygen, and nutrient levels, were measured using in situ sensors and laboratory analysis. Water samples were analyzed for nitrogen, phosphorus, and algal biomass for comparison to environmental conditions. Phytoplankton was preserved for identification in future research. By comparing these environments, this study …

Analysis And Authentication Of An Optical Method For Early Detection Of Harmful Algal Blooms, Cody Schumacher

Theses, Dissertations and Capstones

The proliferation and frequency of harmful algal blooms (HABs) attributed to eutrophication, storm events and a changing climate have been an increasing concern in both lotic and lentic freshwater ecosystems. Methods of detecting HABs have been explored through fluorescent measurement and sample analysis, but are often expensive and time-consuming. A novel smart device application is in development to detect HABs based on images captured and analyzed by machine learning algorithms trained to distinguish potential cyanobacterial blooms. The HABs App model accurately detected cyanobacteria in strong relationship with biovolume concentrations (R² = 0.996) within the Greenup Pool of the Ohio …

A Metadata Analysis Of Unionid Mussels Of The Greenup Pool Of The Ohio River Using Occupancy Modeling And Species Area Curves, Tyler Mitchell Annarino

Theses, Dissertations and Capstones

Although North America contains the largest diversity of freshwater mussels in the world, only ~24% of species in the United States and Canada have stable populations. This group provides unique hurdles for surveying, and current unionid survey protocols include neither longitudinal studies nor randomization of sites. This project conducts a metadata analysis of freshwater mussels in the Greenup Pool of the Ohio River (GPOR) to answer three questions: 1. Does a combination of longitudinal scope, randomization of sites, and historic methodology of surveying result in useful occupancy/detection models (ODMs) of unionids in large streams at the family level? 2. Does …

Effects Of In-Stream Large Woody Debris Management On Riparian Salamander Population Dynamics, Sydney Hermann

Theses, Dissertations and Capstones

The addition of large woody debris (LWD) into streams is an increasingly common habitat restoration method used to support brook trout populations and other sensitive freshwater species. Wood jams create localized reductions of water velocity, increase organic matter retention, intensify overbank flows, and promote habitat heterogeneity. These changes enhance interaction between the floodplain and the stream which can influence forest habitat variables such as leaf litter, soil pH, moisture, and invertebrate abundance. Salamander demographics reflect the stability of these forest habitat variables, and population declines can be indicative of environmental disturbance, stress, or change. Evaluating how this trout-targeted management effects …

Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez

Journal of Earth and Life Science

Wild rice (mannoomin; Zizania palustris) is an aquatic grain that grows in slow-moving rivers and shallow bays throughout northern Minnesota. In Headquarters Bay on Leech Lake, wild rice has served as a cultural staple for Indigenous communities for centuries. However, its population has declined in recent years due to multiple environmental issues. One potential contributor is Eurasian watermilfoil (Myriophyllum spicatum; EWM), an invasive species that forms dense mats capable of outcompeting native aquatic vegetation, including wild rice. EWM was first recorded on the southern shoreline of Leech Lake in 2005 and has since become widespread. This study …

The Effect Of Zebra Mussels On Minnesota Fish Communities, Benjamin D. Strei

Journal of Earth and Life Science

Zebra mussels Dreissena polymorpha are an aquatic invasive species that has been spreading quickly throughout Minnesota water bodies since 1989. Zebra mussels are known to change certain morphological conditions in lakes such as turbidity, phytoplankton abundance, and aquatic invertebrate populations. However, studies showing impacts of the infestation of zebra mussels on the health of a fish community have been hard to prove due to a lack of repeated surveys and a suite of other confounding variables such as natural and seasonal variability, plant community, and lake morphometry. Therefore, the objective of this study is to determine whether zebra mussels have …

Microsatellites Reveal The Population Genetic Structure Of Yellow Perch In Minnesota, Megan Boche

Journal of Earth and Life Science

When analyzing a population’s genetic makeup, looking at variation of individuals and populations is a crucial factor. The management of yellow perch will be aided by this information particularly in regard to stocking or relocation. Microsatellite loci were used to analyze the genetic population structure of yellow perch Perca flavescens within and among 29 sampling areas throughout Minnesota’s basins. Seven microsatellite DNA loci were evaluated, with heterozygosities ranging from 0.41 to 0.78. The Lower Mississippi basin samples showed higher numbers of alleles per locus and greater expected heterozygosities compared to other basins, with Lake Pepin (PEP) exhibiting the highest average …

Assessing Understory Along The Elk River (Hikshari') In Headwaters Forest Reserve, Humboldt County, California, Julie R. Meyers, Aliyah M. Ingram, Caleb N. Larkin, Joshua L. Carpenter

Environmental Science & Management Senior Capstones

Northern California’s extensive logging history and lack of forest management has altered old-growth coast redwood (Sequoia sempervirens) forests, leaving dense, homogenous second and third-growth forest stands. This has led to the use of modern restoration techniques such as variable density thinning (VDT) which aims to rehabilitate old-growth forest conditions by improving stand heterogeneity and light availability for understory species. Our study was done in Headwaters Forest Reserve (HFR) along the Elk River (Hikshari’) Trail in Humboldt County, California. Initially, the project was supervised by the Bureau of Land Management (BLM) Arcata Field Office. However, the 2025 U.S. government …

Aquatic Invertebrate Populations In Roadside Wetlands In Relation To Water Characteristics, Ellen P. Isakson

Journal of Earth and Life Science

The continual habitat destruction and draining of wetland systems makes the need to understand the ecology of roadside wetlands all the more necessary. Roadside wetlands provide valuable habitat to countless aquatic invertebrates, which can provide insight into the health of the wetland system due to their diversity. The objective of this study was to analyze the populations of aquatic invertebrates in roadside wetlands in relation to water characteristics such as pH, salinity, conductivity, water depth and temperature, and dissolved oxygen. This was done by collecting samples of invertebrate populations from roadside wetlands, in addition to data on water quality characteristics …