Ecology and Evolutionary Biology Commons^™

Spatial And Abiotic Effects Of Urbanization On Small Mammal Communities, Bri Casement

Master's Theses

Urbanization, the phenomenon of increasing human population density and artificial structures, is known to decrease the richness, abundance, and diversity of native wildlife populations, fragment natural areas, and increase human and human-commensal animal interactions with wildlife. Dynamics of species persistence in habitat fragments is often understood in the framework of island biogeography theory (IBT), with habitat fragments being analogous to oceanic islands. Despite the conceptual similarities between oceanic islands in IBT and urbanized habitat fragments (fragment size, fragment age, and distance to immigration sources), there are important differences. In urban fragments, the matrix is not completely impassible, habitats within fragments …

Spatial Ecology Of Mountain Lions Throughout Their Distribution In California, Kyle Duncan Dougherty

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

Mountain lions (Puma concolor) have been studied extensively throughout their wide geographic distribution in the Western Hemisphere, but most research has been conducted at relatively small spatial scales. We used GPS telemetry data contributed by researchers in 16 study areas throughout California to advance understanding of mountain lion spatial ecology. First, we investigated multi-scale resource selection of mountain lions relative to spatially varying risk of intentional human-caused mortality associated with livestock depredation management. We show that individuals that proactively avoided mortality risk when selecting home ranges were able to relax their avoidance of risk when making resource selection …

Spatial Ecology Of Mountain Lions Throughout Their Distribution In California, Kyle D. Dougherty

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

Mountain lions (Puma concolor) have been studied extensively throughout their wide geographic distribution in the Western Hemisphere, but most research has been conducted at relatively small spatial scales. We used GPS telemetry data contributed by researchers in 16 study areas throughout California to advance understanding of mountain lion spatial ecology. First, we investigated multi-scale resource selection of mountain lions relative to spatially varying risk of intentional human-caused mortality associated with livestock depredation management. We show that individuals that proactively avoided mortality risk when selecting home ranges were able to relax their avoidance of risk when making resource selection …

Hybridization Between The Rare Gray-Headed Chickadee And The Abundant Boreal Chickadee In The Midst Of Shifting Climate, Matthew R. Armstrong

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

As species respond to changing climate, distributions and abundances may shift and alter species interactions. Hybridization, a relatively widespread phenomenon becoming more common with climate change, can have beneficial and detrimental effects on population growth rates and genetic integrity. Beneficial effects due to the introduction of advantageous alleles and increased genetic diversity may result from hybridization. Species may also accrue fitness costs associated with changing climates if mismatches occur between environmental variables and phenotypes. The gray-headed chickadee, Poecile cinctus lathami, is an extremely rare songbird that has experienced marked declines in recent decades within its restricted distribution in Alaska …

The Relationship Between Changing Land Cover And Benthic Macroinvertebrate Diversity In Choccolocco Creek, Northeast Alabama, Kindall Brown

Theses

Land cover changes, driven by urbanization, agriculture, and deforestation, significantly affect the physical and chemical characteristics of water bodies at both the watershed and riparian levels. At the larger spatial scale, a stream’s surrounding watershed facilitates lateral inputs into the stream that are essential for biodiversity support, hydrological stability, and water quality. When a stream becomes disconnected from the lateral inputs due to urban or agricultural development, the morphology of the stream is significantly altered. On a smaller spatial scale, the riparian zone can act as a buffer to pollutants. The vegetation surrounding the stream bank promotes stability to the …

New Insights On Hybridization In Potamogeton Floridanus (The Florida Pondweed), Kaitlyn R. Sampson

Graduate Theses and Dissertations (2019 - present)

Freshwater ecosystems are some of the most important and highest threatened habitats in the world, and aquatic plants play an important, but often-overlooked, role in maintaining them. Potamogeton is a diverse and ecologically important aquatic plant genus well known for taxonomic difficulty and rampant hybridization. lbis study aimed to 1) test the hypothesis that Potamogeton jloridanus (Florida pondweed) is a hybrid between P. oakesianus and P. pulcher, and 2) to investigate correlations in ecological conditions for the focal species. This study revealed the discovery of a new population of P. jloridanus in Big Coldwater Creek in Santa Rosa Co., FL, …

The Ecological Applications Of Δ17O: Validating A Novel Technique For Assessing Animal Metabolism And Water Intake, Zachary Taylor Steele

Biological Sciences Theses & Dissertations

Animals obtain water via different processes such as drinking, consuming food, and through metabolic processes like at the end of the electron transport chain when atmospheric oxygen is combined with hydrogen to form ‘cytochrome oxidase water’. Assessing animal water flux and metabolism has mainly been conducted via stable isotope analysis (SIA) of biological samples using hydrogen (²H) and oxygen isotopes (¹⁶O, ¹⁷O, and ¹⁸O; Δ¹⁷O), typically using enriched isotope tracers. However, natural abundance isotope modeling offers an approach for conducting SIA of biological samples that differs because it relies on the unique, …

Behavioural Distributions Of Macrophytes In An Oxbow Lake, Dhir Beel With Reference To Its Water Quality In Assam, India, Arup Nama Das, D. K. Sharma

Journal of Bioresource Management

An Oxbow lake, Dhir Beel, situated in Western Assam, India, stands as a habitat for a plethora of plant and animal species, nurturing a vibrant ecosystem within its freshwater environs. This study sought to address concerns surrounding pollution, encroachment, siltation, and overfishing within Dhir Beel. Over a span of three years (2016-2019), samples were meticulously collected from five distinct sites to analyze both water quality and macrophyte populations. Employing the APHA method, the physico-chemical parameters of the water were evaluated, while a comprehensive identification process was undertaken to categorize the macrophytes. These aquatic plants, spanning dicots, monocots, and pteridophytes, were …

Modeling Pelagic Feeding In The Gulf Of Mexico With Implications For Ecosystem-Based Fisheries Management, Rebecca L. Scott

USF Tampa Graduate Theses and Dissertations

The focus of this dissertation was simulating trophic dynamics in the pelagic Gulf of Mexico (GOM) with an emphasis on ecosystem-based fishery management (EBFM) strategies for large pelagic species. Fisheries management in the United States largely utilizes single-species assessments, although managers are increasingly interested in EBFM approaches to better account for ecosystem effects on stocks such as predator/prey dynamics. Production in the surface layer of the pelagic zone is variable with environmental conditions and prey is often concentrated in patches by hydrodynamic features. Production is also transported vertically via diel vertical migration, during which deep-sea species provide potentially key forage …

Climate And Shared Evolutionary History Drive Trait Variation Among Species Of Neotropical Understory Monocots, Eleinis Ávila-Lovera, Oscar M. Vargas, Jennifer L. Funk, Kathleen M. Kay, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Environmental variation commonly drives functional trait diversity within species, among species, and across communities. Climate and shared evolutionary history can both influence trait–environment relationships. We studied variation in plant functional traits among closely related Costus species occurring across environmental gradients, the extent to which this variation occurs within single species, and how that variation may be influenced by shared evolutionary history. We measured leaf, aboveground stem, rhizome, and fine root traits of 17 species of Costus in eight sites in Costa Rica and Panama, which varied in elevation, temperature, and precipitation. We then assessed the relationships among traits and environmental …

Novel Adaptations In Iron Regulation Acquired During Chronic Fungal Cf Infections, Daniel R. Murante

Dartmouth College Ph.D Dissertations

Chronic fungal infections are highly recalcitrant to treatment; we postulated that as populations persist, increasing genetic diversity is reflected in phenotypic heterogeneity, contributing to treatment inefficacies. The study of evolutionary patterns is underrepresented in chronic fungal infections, and to supplement this body of knowledge, we leveraged isolates acquired from four individuals with chronic fungal-dominated cystic fibrosis infections. We evaluated in-host evolution through a whole-genome sequencing approach, comparing multiple isolates obtained from each subject's sputum and bronchoalveolar lavage fluid. Our analysis found non-synonymous mutations that arose in parallel across the independent infections in the gene MRS4, which encodes a mitochondrial …

Evaluation Of Major Physical And Mechanical Properties Of Trembling Aspen Lumber, Dawei Wang, Mengyuan Zhang, Meng Gong, Ying-Hei Chui

Aspen Bibliography

Trembling aspen (Populus tremuloides) is one of the major species within Populus, a predominant genus of hardwoods in North America. However, its utilization has been limited to pulp and paper or wood-based composite boards. This study aimed at evaluating the major physical and mechanical properties of trembling aspen lumber, with an ultimate objective of using this species to produce engineered wood products (EWPs). The testing materials consisted of 2 × 4 (38 mm × 89 mm) trembling aspen lumber pieces in lengths of 8, 10, and 12 feet (2.44, 3.05, and 3.66 m) with two visual grades, …

The Ecosystem As Super-Organ/Ism, Revisited: Scaling Hydraulics To Forests Under Climate Change, Jeffrey D. Wood, Matteo Detto, Marvin Browne, Nathan J.B. Kraft, Alexandra G. Konings, Joshua B. Fisher, Gregory R. Quetin, Anna T. Trugman, Troy S. Magney, Camila D. Medeiros, Nidhi Vinod, Thomas N. Buckley, Lawren Sack

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Classic debates in community ecology focused on the complexities of considering an ecosystem as a super-organ or organism. New consideration of such perspectives could clarify mechanisms underlying the dynamics of forest carbon dioxide (CO₂) uptake and water vapor loss, important for predicting and managing the future of Earth's ecosystems and climate system. Here, we provide a rubric for considering ecosystem traits as aggregated, systemic, or emergent, i.e., representing the ecosystem as an aggregate of its individuals, or as a metaphorical or literal super-organ or organism. We review recent approaches to scaling-up plant water relations (hydraulics) concepts developed for …

Isolation Of Gametophytic Selection And Selective Embryo Abortion In Mimulus Guttatus, Desmond C. Willson

University Honors Theses

A lack of genomic studies examining gametophytic selection (GS) and selective embryo abortion (SEA)--which occur during the reproduction of angiosperms--leaves questions regarding the adaptive and evolutionary effects of these processes. Analyzing deviations from Mendelian segregation offers an avenue for identifying loci targeted by GS and SEA, and their contributions to purging of genetic load. However, other selective processes such as meiotic drive and cytonuclear interactions, as well as pollen and ovule abortion, can cause distortion. To distinguish the effects of GS and SEA from other causes of distortion, we will perform reciprocal crosses between highly homozygous and highly heterozygous individuals …

Removal As A Control Method For Trachemys Scripta Elegans And The Response Of Chrysemys Picta Bellii, Jacob Swanson

University Honors Theses

The red-eared slider is considered one of the most ubiquitous freshwater turtles globally. Several key ecological advantages and life history traits of this species jointly impact growth rates and survivorship of native freshwater turtles where sympatry occurs. Evaluation of current management actions for red-eared slider turtles is limited, resulting in a paucity of information to guide management for the species and conservation of declining native freshwater turtles. We used previously collected mark-recapture and removal sampling data from sites with sympatric populations of red-eared slider and western painted turtles. We examined the effects of control (trapping and removal) of red-eared sliders …

Evidence Of Climatic Influence On Subsistence Strategies At Sage Hen Springs, Nevada, Andrew Rogers

Electronic Theses and Dissertations

Models of settlement patterns in the northwest Great Basin describe a decrease in residential mobility, intensified use of upland spring ecozones, and an increase in diet breadth during the Middle and Late Archaic. Here, I present data collected from the Sage Hen Springs site in northwestern Nevada during a Phase II testing project conducted by the BLM and an analysis of these data focusing on patterns of subsistence and mobility strategies throughout the Archaic. Results of this analysis support existing models of lifeways in the northwest Great Basin at the small scale and point to climatic factors as influences on …

Mixing Trembling Aspen And White Spruce Increases The Understory Vegetation Cover And Improves Soil Properties But Effects Vary With Broadleaf Density, Mostarin Ara, Bradley D. Pinno, Philip G. Comeau

Aspen Bibliography

Despite the importance of species mixtures to ecosystem-based forest management, density effect of broadleaf trees in the mixture on understory vegetation and soil properties are poorly understood. In this study, we examine the effects of trembling aspen [aspen] (Populus tremuloides Michx.) -white spruce [ spruce] (Picea glauca (Moench) Vos) mixtures that vary in the proportion of aspen on understory vegetation cover, soil nutrient supply rates, and soil properties. Data were collected from an established study located in Alberta, Canada at age 20 and included the following treatments: 1. Natural regeneration of pure aspen; 2. Retaining only …

The Effects Of Wildfire Burn Severity On Bee And Wasp Communities Two Decades Post-Fire, Alaina K. Smith

Electronic Theses and Dissertations

While fire is a natural disturbance in many global ecosystems, anthropogenic changes are affecting fire frequency, severity, and seasonality. Disturbances like wildfire affect bee and wasp communities, but recent meta-analyses are conflicted about whether fire harms or benefits insect pollinators. We investigated the lasting effects of wildfire burn severity on wild bee communities and floral resource availability across different burn severities in two-mixed severity fires that burned >20 years ago. We found that high severity fire has positive effects on bee diversity that are associated with severity-mediated changes to the floral community. We also studied the effects of wildfire burn …

The Polyaneuploid Cancer Cell State And Therapeutic Resistance: Eco-Evolutionary Dynamics In Structured Populations, Anuraag Bukkuri

USF Tampa Graduate Theses and Dissertations

In this dissertation, I develop and apply eco-evolutionary modeling techniques to understand how the polyaneuploid cancer cell (PACC) state, entered when aneuploid cells exit the cell cycle after S phase and undergo a whole genome duplication, contributes to therapeutic resistance. Since resistance remains one of the primary causes of treatment failure in cancer patients, it is critical to understand how such demographic state transitions allow for acclimatization of cancer cells to therapeutic stressors and how they interact with evolutionary processes to promote irreversible resistance.

In Chapters Two and Three, I lay the foundation for this work. In Chapter Two, I …

Concepts In Animal Parasitology, Scott L. Gardner, Sue Ann Gardner

Zea E-Books Collection

Note that this version of the textbook has been superceded by the one updated in 2026, available at the UNL Pressbooks site.

The hard copy version that is for sale at lulu.com is the old version.

"This is a textbook covering concepts in animal parasitology. It is meant to be used by students, teachers, professors, researchers, and members of the public who are interested in learning about animal parasite biology, systematics, taxonomy, zoogeography, and ecology. The primary intended audience is upper-level undergraduate or graduate university students who have knowledge of basic biology and, particularly, basic animal biology. (863 pages, …

A Library Of 39 Plant Peroxidases: Plants From The Families Cucurbitaceae And Brassicaceae Show Promising Peroxidase And Peroxygenase Activity, Sally Hess

Senior Honors Theses

Peroxidases are enzymes that reduce reactive oxygen species (ROS) and oxidize organic substances in living cells. The textile industry, wastewater treatment plants, immunological laboratories, and diagnostic laboratories have extensively used horseradish peroxidase for their oxidating needs. This research aims to provide a tool for identifying potentially useful sources of peroxidases in addition to specifically pinpointing a novel peroxygenase in jalapeño seeds. By using two widely accepted peroxidase assays, the guaiacol assay and the fluorophenol assay, fruits of the genus Cucurbita and roots or leaves of the family Brassicaceae were seen to have high peroxidase activity. Additionally, novel peroxygenase activity was …

A Multispecies Hierarchical Model To Integrate Count And Distance-Sampling Data, Neil A. Gilbert, Caroline M. Blommel, Matthew T. Farr, David S. Green, Kay E. Holekamp, Elise F. Zipkin

Institute for Natural Resources Publications

Integrated community models—an emerging framework in which multiple data sources for multiple species are analyzed simultaneously—offer opportunities to expand inferences beyond the single-species and single-data-source approaches common in ecology. We developed a novel integrated community model that combines distance sampling and single-visit count data; within the model, information is shared among data sources (via a joint likelihood) and species (via a random-effects structure) to estimate abundance patterns across a community. Parameters relating to abundance are shared between data sources, and the model can specify either shared or separate observation processes for each data source. Simulations demonstrated that the model provided …

Rewiring The Sex-Determination Pathway During The Evolution Of Self-Fertility., Yongquan Shen, Shin-Yi Lin, Jonathan Harbin, Richa Amin, Allison Vassalotti, Joseph Romanowski, Emily Schmidt, Alexis Tierney, Ronald E Ellis

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Although evolution is driven by changes in how regulatory pathways control development, we know little about the molecular details underlying these transitions. The TRA-2 domain that mediates contact with TRA-1 is conserved in Caenorhabditis. By comparing the interaction of these proteins in two species, we identified a striking change in how sexual development is controlled. Identical mutations in this domain promote oogenesis in Caenorhabditis elegans but promote spermatogenesis in Caenorhabditis briggsae. Furthermore, the effects of these mutations involve the male-promoting gene fem-3 in C. elegans but are independent of fem-3 in C. briggsae. Finally, reciprocal mutations in these genes show …

Geographic Distribution: Smilisca Baudinii (Mexican Treefrog). Usa: Florida: Escambia Co., Louis A. Somma, Justin K. Anto, Jakira A. Davis

Papers in Herpetology

Geographic distribution note for Smilisca baudinii, the Mexican treefrog, from Escambia County, Florida, United States.

Nou Spring Field Days And Annual Meeting, 125th Anniversary Of The Nebraska Ornithologists’ Union, Birding Bowl Kickoff Weekend, Lincoln, Mary 3–5, 2024, Janis Paseka

Nebraska Bird Review

The NOU Annual Meeting and Spring Field Days were held in Lincoln on May 3-5, 2024, with 80 in attendance. This year is the 125th anniversary of the founding of the Nebraska Ornithologists’ Union, and this meeting also served as the kickoff of the Nebraska Birding Bowl.

Field trips were led by Olivia DaRugna, Thane Dinsdale, Joe Gubanyi, Thomas Labedz, Jason St. Sauver, T. J. Walker, and Michael Willison. Destinations included Wilderness Park, Bluestem Lake SRA, Killdeer WMA, Cottontail WMA, Pawnee Lake SRA, Branched Oak Lake, Butler County Prairie-Chicken lek, Marsh Wren Saline Wetland, Spring Creek Prairie, and Conestoga Lake …

The Nebraska Bird Review (June 2024) 92(2), Whole Issue

Nebraska Bird Review

Spring Field Report, March–May 2024, by W. Ross Silcock

The Early Years of the Nebraska Ornithologists’ Union: People and Publications, by Daniel W. Leger

NOU Spring Field Days and Annual Meeting, 125th Anniversary of the Nebraska Ornithologists’ Union, Birding Bowl Kickoff Weekend, Lincoln, May 3–5, 2024, by Janis Paseka

Subscription and Organization Information

Spring Field Report, March–May 2024, W. Ross Silcock

Nebraska Bird Review

A major concern this spring was the widely lamented shortfall in numbers of migrant warblers and the shortened duration of the migration, with most sightings relatively early. Numbers of migrant warblers east of the 100th meridian were investigated by Joel Jorgensen and Stephen Brenner and the scarcity was indeed found to be supported by eBird data; see the “News and Updates” section in Birds of Nebraska-Online (BONO). At Oliver Reservoir in the Panhandle, however, Steven Mlodinow found that migration was at least normal for a range of common migrants, with some migrants above the levels of the last four years. …

Evolution And Adaptation To Temperature In Thermotogota, Anne Amelia Farrell

Dartmouth College Ph.D Dissertations

Life thrives across incredibly diverse environmental conditions, yet most organisms are restricted to growing within a narrow range around their optimum growth temperature (OGT). The evolutionary events leading to changes in OGT are poorly understood, and it is uncertain if specific genes are required to thrive at a particular temperature. The bacterial phylum Thermotogota is an excellent model for the evolution of OGT. It comprises mesophilic, thermophilic, and hyperthermophilic members that collectively grow between 20°C and 90°C.

In this work, I analyze the history of OGT in the Thermotogota phylum and show how horizontal gene transfer contributes to the evolution …

Aspen As Firebreaks At The Development Fringe, Kevin Krasnow, Paul C. Rogers

Aspen Bibliography

Quaking aspen (Populus tremuloides) forests are widely known and prized for their numerous values—biodiversity, habitat, forage, recreation, aesthetics, and others—including as a deterrent to wildfire. This reputation for stopping or slowing flames is explored here, alongside measures that may be taken to facilitate thriving aspen communities near human developments. It is clear that science supporting the premise of aspen as an effective firebreak is far from complete. Yet, how can we benefit from what we do know on this topic to increase the probability of preventing structural fire damage, while also encouraging the valued characteristics of aspen ecosystems?

Climate Considerations For Quaking Aspen Conservation, Douglas Shinneman, Susan Mcilroy, Paul C. Rogers

Aspen Bibliography

Human-caused climate change alters ecosystem processes ranging from local to global scales. As a consequence of climate change we should expect increased rates and intensities of disturbance events. Though we are only beginning to understand what those impacts might be to aspen forests and their diverse plant and animal assemblages, recent science suggests there may be unavoidable effects. In the face of anticipated climate-ecosystem challenges, contemporary managers are searching for guidance on preserving aspen resilience. We suggest crafting strategic yet cautious approaches to minimize effects and facilitate broad resilience. For instance, monitoring conditions in and near aspen forests will help …