Life Sciences Commons^™

Impact Of Invasive Pine Trees And Their Ectomycorrhizal Fungi Symbionts Upon The Properties And Functions Of Soils In Southern Hemisphere Eucalyptus Forests, Jack T. Baker

Honors Theses

P. radiata trees are invading Southern Hemisphere Eucalyptus forests within New Zealand and southeastern Australia, resulting in a novel codominant forest system. This codominant invasion is unique relative to other pine invasions throughout the Southern Hemisphere. Ectomycorrhizal fungi (EMF) play an important role in all pine invasions and are found within each instance of invasion. The impact of ectomycorrhizal fungi and Pinus trees upon the properties of the soil within Eucalyptus forests is not very well studied nor understood. Our study sought to provide insight into the implications of this invasion upon the soil, and consequently the ecosystem as …

Ecology Of Beech Leaf Disease: Identifying The Forest Conditions Correlated With Infection In Northeast Ohio, Blake Logan

Research Symposium

Beech Leaf Disease (BLD) is a novel, poorly-understood threat to forests across North America. Since its discovery in northeast Ohio in 2012, the disease has affected staggering numbers of beech trees (Fagus grandifolia), resulting in increased sapling mortality. In the near future, mortality in symptomatic mature trees is expected to follow. The symptomatic striped leaves result from the activity of the nematode Litylenchus crenatae ssp. mccannii, but the precise role this organism plays in transmission and infection is currently unknown.

Oberlin College has been conducting forest demography research at Chance Creek, a nature preserve in Lorain county, since 1974. Every …

A Population Study Of The Freshwater Turtles Of The Recently Expanded Lake Hydaway In Campbell County, Virginia, Joshua Sorenson

Senior Honors Theses

Freshwater turtles are an important part of the ecological systems in central Virginia. At the recently expanded Lake Hydaway, there are several turtle species for which their population characteristics were unknown, especially the prolific Eastern Painted Turtle (Chrysemys picta picta) and Red-bellied Cooter (Pseudemys rubriventris). For five weeks, the lake was surveyed for turtles using hoop nets, and the turtles were marked and measured. Population characteristics such as carapace length and sex ratio for the Eastern Painted Turtle and Red-bellied Cooter were calculated, as well as population estimates for those two species. The Red-eared Slider ( …

Designing An Optimal Thermal Preference Arena For Southern Cricket Frog (Acris Gryllus) Juveniles, Eleanor E. Briggs, David M. Phillips Jr.

Honors Theses

Climate change has been altering ecosystems across the world at a substantial rate, disrupting the delicate ecophysiological relationships between ecosystems and the organisms that live in them. Ectotherms, such as amphibians, rely on external temperatures to behaviorally thermoregulate, making it especially imperative to study their thermal biology. Thermal preference, which assesses the environmental temperature an organism would seek out in the absence of external stimuli, provides valuable information about an amphibian’s thermal biology and can be used to predict the effects of climate change on a species or population. A commonly used method to measure thermal preference is an arena …

Observations Sur La Repartition Et L’Ecologie De Luzernes Annuelles Et De Trefle Souterrain En Corse, J M. Prosperi, V Gensollen, I Olivieri, P Mansat

IGC Proceedings (1977-2023)

Des missions de prospection du genre Medicago, realisees entre 1985 et 87, ont permis de mieux connaitre !es relations especes-milieux, pour mieux cerner la variabilite de ces especes, leur distribution et la gamme de milieux favorables a chacune d'entre-elles.

Market Structure Evolution In The U.S. Automobile Industry: A Review Of Diversity And Concentration Metrics, P.V. (Sundar) Balakrishnan

AMTP Proceedings 2025

I examine the evolution of market structure in the U.S. automobile industry from 1937 to the present, focusing on the application of both traditional and novel diversity and concentration metrics. I use the Herfindahl-Hirschman Index (HHI), Comprehensive Concentration Index (CCI), and newer metrics from fields such as ecology and genetics to uncover insights into the shifting dynamics of market power, firm turnover, and industry stability. The U.S. automobile industry, characterized by consolidation and technological advancement, provides a unique case study for analyzing long-term market evolution. I contribute to the literature by synthesizing a broad range of diversity metrics and offering …

Ecology Of Ixodes Scapularis Say: Experimental And Observational Studies With Social Perspectives On Ticks And Tick-Borne Diseases, Kaitlin M. Mcdonald

Dartmouth College Ph.D Dissertations

Tick-borne diseases are a growing concern globally. Understanding the factors that influence tick ecology and people’s understanding of that ecology is crucial for developing effective tick management and disease prevention strategies. In this work, I investigated fundamental questions about the ecology of a primary vector of medically important pathogens in the United States, the blacklegged tick Ixodes scapularis Say, and identified common misconceptions about ticks and tick-borne diseases on social media. First, I examined the effects of temperature and moisture stress on the movement of adult female I. scapularis in laboratory experiments. Using a Drosophila Activity Monitor, ticks were exposed …

Advances In Research And Development With Sylosanthes And Other Tropical Pasture Legumes, D F. Cameron, C P. Miller, L A. Edye, J W. Miles

IGC Proceedings (1977-2023)

The last 20 years have seen major advances in research and development wilh tropical legumes. Research advances have been closely associated with substantial increases in the number and diversity of genetic resource collections, Release of a wide range of new cultivars has been based on selection for plant adaptation, persistence and productivity, screening for resistance to pest's and diseases, and the development of efficient seed production. Determination of fertiliser requirements and grazing management practices has resulted in sustainable animal production from legume-based pasture systems. Extensive pasture development has now occurred in both high and low input systems. Options vary from …

Economic And Ecological Features Of Livestock And Wildlife Utilization In Africa, J I. Barnes

IGC Proceedings (1977-2023)

This paper looks at livestock and wildlife utilisation in Africa within the framework of total economic value (TEV), which includes both utilisation and biodiversity values. In Africa, traditional use of wildlife involves open access systems on public land, Here, free ranging, public wildlife resources are used to produce subsistence or marketed meat and skins at smaII scale. Traditional livestock systems involve open access use of rangelands. Here, livestock are kept at small ·scale to produce draft power, milk, meat and as a store of .value. Commercial use of wildlife involves restricted access systems on both public and private lands. Here, …

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 …

Stability In Rangelands: Ecology And Economics, B H. Walker

IGC Proceedings (1977-2023)

Examples of changes in rangelands are presented relating to changes in livestock number, plant species. composition and soil changes (associated with changes in production), The mechanisms Involved are described, using examples, under the headings: event-driven change, threshold effects, non-linear and hysteresis effects, effects of spatial variation, significance of temporal variation, and interactive effects. The implications for management are presented in the form of a proposed optimal control model which maximises a complex function of welfnre based on long-term net economic benefit, in which stocking rate effects on the state of the rangeland feed back on to economic return.

The Effect Of Two Common Herbicides On The Growth And Development Of Two Anuran Species (Boreorana Sylvatica And Dryophytes Chrysoscelis), Jerica Eaton

Masters Theses & Specialist Projects

Amphibian populations have been declining globally since the 1950s. Many species that have experienced declines are viewed as 'environmental indicators' that reveal habitat degradation. Declines can be attributed to several factors, including chemicals used in agriculture, such as Roundup and Atrazine. Agrochemicals contaminate water bodies through runoff or leaching and cause alterations to aquatic ecosystems. This study evaluated the effects of herbicide usage on two wild anuran populations using wood frogs (Boreorana sylvatica) and Cope’s gray tree frogs (Dryophytes chrysoscelis) as a model. We determined the effect of the herbicides at two concentrations, a high concentration …

Evolutionary Stasis In Life History Traits Between Xenophallus Clades Isolated During Pliocene Marine Incursions, Elias Johnson, Jerald B. Johnson

Library/Life Sciences Undergraduate Poster Competition 2025

Why do some species fail to evolve? The chiral livebearer, Xenophallus umbratilis, is found in Central America. Populations within this species have been isolated from each other for millions of years due to marine incursions, big rivers, and ecological filters downstream, leading to divergent clades (figure below). However, these isolated populations persist under similar ecological conditions, including the absence of predators and in similar headwater habitat types.

Acoustic Monitoring Of Oak Toads (Anaxyrus Quercicus), A Longleaf Pine (Pinus Palustris) Ecosystem Endemic Amphibian, Alex Ward Foote

Theses, Dissertations and Capstones

The Longleaf pine ecosystem is one of the most endangered ecosystems in the world with only 3% remaining. Many endemic species to the longleaf pine ecosystem are also in decline and suffer from habitat loss resulting from fire exclusion, urbanization, agriculture, and industrial silviculture. Oak Toads (Anaxyrus quercicus) are a longleaf pine ecosystem obligate; the species is experiencing declines across its range and only has protections in Virginia and North Carolina. We used data from an array of Automated Recoding Units across four years (2013, 2014, 2015, 2019) at three state-owned wildlife management areas to capture audio files …

Climate And Gypsum Parent Material Shape Biocrust Communities And Moss Ecology In The Chihuahuan And Mojave Deserts, Katelyn Gobbie, Nicole Pietrasiak, Brian M. Jusko, Rebecca E. Drenovsky

2025 Faculty Bibliography

Biological soil crust communities (biocrusts) establishing on gypsum soils have been well-documented for their prolific appearance and rich diversity of lichens and bryophytes. However, studies characterizing gypsum biocrusts have occurred primarily outside of the U.S., most of which lack comparisons to other soil types. We conducted intensive field surveys to evaluate the ground cover and frequency of biocrust functional groups and moss species on gypsum and non-gypsum soils in the U.S. regions with the most extensive gypsum outcrops, the northern Chihuahuan and eastern Mojave Deserts. Study sites were stratified by geomorphology and paired, so that every gypsum site was matched …

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 …

René Dubos: An Annotated Bibliography, Carol L. Moberg

René Dubos: An Annotated Bibliography

René Dubos (1901–1982), a prominent 20th century scientist, humanist, and philosopher, was a prolific author. Affiliated for more than 50 years with The Rockefeller Institute for Medical Research/The Rockefeller University, his studies ranged from antibiotics and the role of bacteria in human diseases to formulating broad ecological and environmental questions affecting human health and disease. His seminal writings explore a lifelong belief that a living organism—whether microbe, human being, society, or the Earth itself—could be understood only through its relationships with everything else.

This comprehensive bibliography of more than a thousand works by René Dubos includes brief annotations for each …

How Individual Traits Predict Distribution Patterns And Community Convergence, Zachary K. Lange

Biology Dissertations - Archive

One of the fundamental questions in biology is whether natural conditions lead species and communities toward predictable outcomes. Answering this question requires understanding how traits of individual organisms are connected to species- and community-level patterns. In Chapter 2, I examined how thermal physiology and environmental temperatures interact to determine the distribution patterns of Anolis lizards on the Greater Antilles. I combined lab-measured thermal traits (critical thermal minimum: CT_min, critical thermal maximum: CT_max, thermal preference: T_pref) with occurrence and abundance data from 21 species of Anolis lizards collected from extensive mark-resight surveys of communities across …

The Evolution Of The Stress Response In The Trinidadian Killifish: Ecological Drivers And Maternal Mediation, Mikaela E. Feder

Biology Dissertations - Archive

Ecological variables can induce the stress response in organisms. Yet, few studies have tested for evolutionary shifts in stress responses across ecological gradients. In these studies, we used Trinidadian killifish found in sites with predators (high predation, HP) and sites where they are the only fish present (killifish only, KO). HP and KO populations differ in a suite of behavioral and life-history traits, making the Trinidadian killifish an excellent model to examine evolutionary physiology. My dissertation addresses the knowledge gap by examining: (1) how baseline cortisol differs in wild-caught Trinidadian killifish found in HP and KO sites, (2) the influence …

Unveiling The Bacterial Communities Of Aphaenogaster: Taxonomic Composition, Developmental And Species Influences, And The Impact Of Climate Change, Lily Kelleher

West Chester University Master’s Theses

Ants are vital keystone species in many ecosystems because they provide ecosystem services such as: seed dispersal, soil bioturbation, and pest control. However, ant bacterial symbioses remain largely unstudied, but these interactions are crucial because microbes play a vital role in the ants’ overall health. Today, global climate change is impacting our biodiversity, and we can use information about how changing temperatures impact the symbiotic bacterial communities associated with ants to predict future impact. Aphaenogaster rudis and A. fulva remain understudied in terms of their bacterial community and are important North American species. For this study, ants from several colonies …

Dictyostelids: The Second Major Group Of Slime Molds, P. Liu, Z.J. Zhang, J.H. Ge, Y. Zou, Z. Li, S. Li, Y. Li, S.L. Stephenson

Biological Sciences Faculty Publications and Presentations

The dictyostelids (also called cellular slime molds or social amoebae) are among the more abundant and widespread groups of microorganisms in terrestrial ecosystems. Despite this fact, they are totally unknown to most people, who sometimes confuse the dictyostelids with myxomycetes (or plasmodial slime molds). The first dictyostelid (Dictyostelium mucoroides) was described by the German Oskar Brefeld in 1869. More than 180 species are now known, and these organisms have been recorded from the high arctic to the subantarctic. The primary microhabitat for dictyostelids is the soil/humus layer on a forest floor, but they also occur in a number of other …

Shrubsteppe Birds Under Fire: Guiding Post-Wildfire Habitat Restoration In The Whiskey Dick And Quilomene Units, Washington, Kevin Clements

All Master's Theses

Bird species, globally, are declining at an alarming rate. Birds of the shrubsteppe are particularly vulnerable to habitat loss caused by agricultural development, invasive vegetation, and heightened wildfire frequency and severity. Fire and invasive vegetation create a positive feedback cycle that threatens complete conversion of shrubsteppe to grasslands. Restoring habitat following wildfire is a top priority for land managers. As bioindicators of ecosystem health, bird populations reflect landscape changes and restoration efficacy. I analyzed bird populations in the Whiskey Dick and Quilomene units of the L.T. Murray Wildlife Area in Kittitas County, Washington following the 2022 Vantage Highway fire. Using …

The Responses Of Insect Herbivores And Local Food Webs To Invasive Shrubs, Logan W. Huber

Browse all Theses and Dissertations

Invasive species cause widespread ecological disruption and economic loss. Invasive plants in particular have the potential to reshape forest food webs from the bottom up. However, the extent to which herbivores colonize and assimilate invasive plants into their diets remains unclear. To address this, I surveyed caterpillar abundance, richness, and herbivory on two invasive shrubs, Lonicera maackii and Elaeagnus umbellata, across regions differing in infestation history. Lonicera maackii supported lower overall caterpillar abundance and richness but hosted a more diverse and abundant caterpillar community in the heavily infested region. E. umbellata supported robust caterpillar communities and experienced herbivory levels comparable …

Determinants Of Bat Activity And Habitat-Use At Runkle Woods And Huffman Metropark, Ohio, Heidi E. Orloff

Browse all Theses and Dissertations

North American bats are an excellent control of pests as most are insectivorous feeders. They face numerous threats including habitat loss, anthropogenic development, disease (White-nose Syndrome), and potentially artificial light at night (ALAN). It is important to track species populations and habitat-use to determine the magnitude of effects from these threats. Acoustic monitoring has proven a useful and non-invasive method for tracking bat populations. In my research, I conducted stationary acoustic surveys of bat activity at Wright State University’s Runkle Woods and nearby Huffman MetroPark during the summers of 2023 and 2024. I recorded bat calls in three different habitats …

Impacts Of Salinity And Drought On Growth And Carbon Sequestration In Acorus Americanus And Carex Scoparia, Eleora L. Mantle

Browse all Theses and Dissertations

From the late 18th century until the 1980s, Ohio lost close to 90% of its wetlands. Despite increased efforts to maintain what is left, many freshwater marshes are still being degraded due to pollutants, such as road salt, and the impacts of climate change. This study sought to understand how both road salt and drought could impact the health and carbon sequestration of two wetland species, Acorus americana and Carex scoparia, to better understand tolerance. To do this, both species were separated into groups and subjected to varying salt concentrations and drought conditions. After 9 weeks of treatment, plants were …

Benthic Algal Biomass And Productivity Across Depth Gradients In Lakes Michigan And Erie, Ahmed Ogidan

Browse all Theses and Dissertations

Benthic primary production is poorly quantified in the Laurentian Great Lakes relative to phytoplankton-based production. We measured benthic chlorophyll and benthic primary productivity on soft sediments and Dreissena shells along depth gradients in Lakes Erie (2024) and Michigan (2025) during EPA Cooperative Science and Monitoring Initiative cruises. We measured benthic chlorophyll fluorometrically and estimated benthic primary productivity using non-invasive oxygen exchange incubations. We used PAM fluorometry to characterize photosynthetic-irradiance relationships on mussel shells and sediments in Lake Michigan. In Lake Erie, sediment chlorophyll ranged from 20 to 150 mg m⁻², with highest values in the central basin. In Lake Michigan, …

Frozen Green Leaves As Potential Nutrient Subsidies In North American Mangrove Ecosystems, Katelyn Overstreet, Emily M. Dangremond, Ilka C. Feller

Biological Sciences Faculty Publications

Avicennia germinans, the black mangrove, has shifted its range limit northward, and increased in abundance in the Southeastern United States. In January 2018, a 3-day freeze event caused substantial defoliation of green leaves in A. germinans near its northernmost range limit in St. Augustine, FL. During their recovery, plants that lost their leaves grew similarly to plants fertilized with nitrogen, leading to the hypothesis that freeze-killed green leaves (frozen green) may have acted as a fertilizer. To assess the value of frozen green litter as a nutrient subsidy, we performed an experiment in which A. germinans seedlings were grown …

A Blueprint To Greener Shorelines: Advancing The Effectiveness, Sustainability, And Widespread Adoption Of Coastal Nature-Based Solutions Through Transdisciplinary Research, Taylor M. Sloey, Sierra Hildebrandt, Rebecca L. Morris, Matthew V. Bilskie, Aaron Bland, David Bushek, Gabriella Dipetto, Daniel Elefant, Vincent Encomio, Ramin Familkhalili, Christine Hladik, Danielle Kreeger, Avery B. Paxton, Cindy M. Palinkas, Latina Steele, Andrew Scheld, Daisuke Taira, Jason D. Toft, Armando J. Ubeda, Christine Whitcraft, Donna Marie Bilkovic

Biological Sciences Faculty Publications

Coastal nature-based solutions (NbS) have emerged as powerful tools to enhance sustainable development and ecological restoration goals. As a rapidly growing field spanning across social, political, ecological, economic, and engineering disciplines, it is critical that researchers working in coastal NbS regularly attempt to identify emerging focal areas for scientific inquiry. Following the 27th Biennial meeting of the Coastal and Estuarine Research Federation, we provide a transdisciplinary perspective (including biologists, engineers, oceanographers, geoscientists, economists, and facilitators of workforce training programs) of pertinent research questions that, if answered, will advance the effectiveness, sustainability, and widespread adoption of coastal NbS. These suggestions for …

Acer Rubrum: Descending Towards Forest Dominance, Elyssa L. Pearson, Christopher M. Gough

UROP Posters

Acer rubrum, more commonly known as the red maple, is a hardwood, late successional species of tree commonly planted for its deciduous nature and vibrant coloring of its leaves in the beginning of autumn (Abrams, 1998). The species is very tolerant of varying light and soil moisture levels and often dominates sub and mid-canopy levels of hardwood forests (Missouri Botanical Gardens). It was hypothesized that as the I moved from an upland location to a lowland location near a wetland that the A. rubrum trees would be more productive and have a greater above ground biomass. This was not …

Heterospecific Coprophagy In The White-Tailed Deer Odocoileus Virginianus (Zimmermann, 1780) In Costa Rica, Mora Manuel Jose, Juan De Dios Astorga-Acuña

Biology Faculty Publications and Presentations

Animals may engage in coprophagy, including heterospecific coprophagy, where they consume the feces of other species. The white-tailed deer, Odocoileus virginianus, primarily feeds on plant material, such as tender forbs and shrub shoots. This report documents a case of heterospecific coprophagy by the white-tailed deer in Costa Rica, where two individuals were observed consuming domestic horse feces. The reasons for heterospecific coprophagy in ruminants like the white-tailed deer are unclear. Nutritional supplementation, microbial transfer, or other ecological factors may play a role in this behavior. However, such a behavior also poses risks, including the transmission of diseases and parasites from …