Ecology and Evolutionary Biology Commons^™

Interactive Effects Of Fungal Community Structure And Soil Moisture On Wyoming Big Sagebrush Performance, Arden Marlene Engel

Boise State University Theses and Dissertations

Large swathes of the North American sagebrush steppe have been converted to grazing and agricultural use. Remaining fragmented areas are threatened by invasive annual grasses and associated perpetuation of increased fire frequency, with efforts to restore sagebrush after fire largely unsuccessful. Lack of success may be due, in part, to poor interactions between sagebrush seed sourced from distant locations and unfamiliar soil fungi.

A greenhouse experiment was designed to evaluate effects of soil fungal community composition on sagebrush reestablishment by answering: (1) How does inoculation with ‘coevolved’ versus ‘foreign’ fungal inoculum impact sagebrush fitness? (2) How does moisture availability modify …

Identifying Sources Of Landscape Variation To Improve Predictions Of Post-Fire Sagebrush Steppe Recovery, Cara Applestein

Boise State University Theses and Dissertations

Sagebrush steppe ecosystems are endangered landscapes, threated by the annual grass-fire cycle where invasion by annual grasses drives larger fires and larger fires drive invasion. Despite extensive input of resources by land management agencies, restoration of these ecosystems is notoriously variable and difficult to predict. Understanding and accounting for variation is key to effectively allocating limited resources and having success in restoring burned sagebrush landscapes. I utilized Bayesian modeling to assess how variation in weather, seed dispersal, and topography/slope/landscape position affects understanding of post-fire sagebrush-steppe recovery and how we can best incorporate sources of variation into models predicting where plant …

A Coupled Human And Natural Systems Approach To Studying Recreation On Public Lands, Madeline C. Aberg

Boise State University Theses and Dissertations

Outdoor recreational use has increased rapidly in the western United States in recent years, which provides more people with opportunities to enjoy public lands and benefit from recreation. However, increased recreation can lead to negative social and ecological impacts that degrade both natural resources and the recreation experience. I used a Coupled Human and Natural Systems (CHANS) approach to study recreational use at the Morley Nelson Snake River Birds of Prey National Conservation Area (NCA) in southwest Idaho. This approach considers the human and natural systems, feedbacks within the systems, and effects from telecoupled influences outside of the site, which …

Vibroacoustic Response Of The Tympanic Membrane To Hyoid-Borne Sound Generated During Echolocation In Bats, Chelsie Snipes

Electronic Theses and Dissertations

The hyoid apparatus in laryngeally echolocating bats forms a mechanical connection between the larynx and auditory bullae and has been hypothesized to transfer the outgoing echolocation call to the middle ear during echolocation call emission. We used µCT data to build models of the hyoid apparatus and middle ear from six species of bats and used finite element modeling (FEM) to measure the vibroacoustic response of the tympanic membrane due to hyoid-borne sound generated during echolocation. We found that hyoid-borne sound in all six species stimulated the eardrum within a range likely heard by bats. Although there were minor differences …

Urbanization Affects Web Abundance And Aggregation Of A Funnel‑Weaving Spider, Agelenopsis Pennsylvanica (Agelenidae), Brandi J. Pessman, Madison Hays, Earl Agpawa, Eileen Hebets

Eileen Hebets Publications

Animals distribute themselves within habitats based on a variety of environmental conditions, including those impacted by urbanization. Suspected global declines in urban arthropod biodiversity have required that we examine how urban conditions affect the distribution of this ecologically important group. Throughout North America, funnel-weaving spiders (Agelenidae) are prevalent across urban habitats and actively choose sites to build webs. We compared Agelenopsis pennsylvanica abundance and distribution between two distinct urban habitats: an urban center (university campus) and an urban forest (city park). These urban habitats differed significantly in features like plant diversity and proximity to roads and highways. We searched along …

Effect Of Temperature On The Microbiome Of A Laboratory-Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna L. Mitchell

Honors Theses

Haemaphysalis longicornis ticks are invasive to the United States with potential to transmit several tick-borne pathogens that are native to the United States. Based on existing locations of H. longicornis in its native regions in Asia, as well as its invasive populations that are established in the United States, several geographic range prediction models have been produced to help understand future range expansion and distribution of this invasive tick in North America. Unfortunately, these models do not all agree and there is uncertainty associated with the potential geographic range expansion of H. longicornis ticks in North America. Climate can affect …

Determination Of Cadmium Uptake In Crassostrea Virginica Shell Under Controlled Conditions, Joseph John Pavelites Ii

Graduate Theses and Dissertations (2019 - present)

The objective of this thesis was to meet growing demand for the development of environmental biomonitors that protect ecosystems and public health. To do this, I determined the potential of oyster shell as a bioindicator of cadmium (Cd) in the environment by determining the mode of Cd uptake and relationships between Cd concentrations in the environment, shell, and soft tissues of juvenile eastern oysters (Crassostrea virginica Gmelin). I performed a review of the literature on the ability of oyster shell to retain metal contaminants and the factors that could affect this process (Chapter 2). I then reared C. virginica …

Linking Decomposition Reactions In Arctic Soils To Microbial Enzyme Production, Jane Karen Martinez

Open Access Theses & Dissertations

Microbial processes such as soil enzyme production are a major driver of decomposition and a current topic of interest in arctic soils due to the effects of climate warming. Despite the advances in understanding soil enzymes, there are still knowledge gaps regarding the role of enzymes in decomposition. In this dissertation, I addressed three of those gaps in the following chapters: (Ch.2) to explore the location of enzymes within the soil matrix, (Ch.3) to identify peptides matched to soil enzymes produced by microorganisms for organic matter decomposition, and (Ch.4) understand the longevity of enzymes in the soil after microbial production. …

Characterizing Spatial Variability In Soil Co2 Fluxes In The Chihuahuan Desert Using Geostatistical Techniques, Viridiana Orona

Open Access Theses & Dissertations

Spatial variability in soil CO2 efflux across landscapes is an important feature of the â??Critical Zoneâ?? within dryland ecosystems. In dryland critical zones, resources are often distributed in patches or resource islands. Although this is particularly true in natural settings, the significance of spatial variability in CO2 efflux and its patterns also extends to dryland agriculture. In both irrigated and unirrigated systems, human management practices can significantly impact both organic and inorganic carbon cycling processes, highlighting the importance of studying CO2 efflux in these systems. We examined the spatial patterns of soil CO2 efflux and quantified the magnitude and scale …

Temporal Trends In Dryland Soil Carbon Fluxes In Response To Artificial And Natural Pulsed Moisture Events, Briana Alyce Salcido

Open Access Theses & Dissertations

Critical zone processes in drylands play a crucial role in the global carbon cycle, and one of the most important processes is soil CO2 efflux at the interface between soils and the atmosphere, which represents a main pathway for loss of carbon. Predicting the carbon dynamics at this interface is challenging due to the complexity of belowground processes, which include both biotic (soil respiration) and abiotic (calcite precipitation) production of CO2, as well as transport processes that include both diffusive and advective components. In this study, we aimed to investigate the contribution of soil air displacement to soil CO2 efflux …

Revision, Description, And Diagnosis Of Adult And Larval Pycnopsyche Spp. (Trichoptera: Limnephilidae) Using Morphological And Molecular Methods, Matthew Green

All Dissertations

The genus Pycnopsyche Banks, 1905 (Trichoptera: Limnephilidae) is the 2nd most species-rich genus of Nearctic Limnephilidae. Larvae and adults are ecologically diverse and widespread throughout eastern North America. Larvae construct cases from mineral or plant material and are frequently used by biomonitoring professionals at the species level to monitor trends in water quality. However, only two species of Pycnopsyche are currently separable as larvae, with diagnosis limited by the number of unknown larvae associated with known adults. Using morphological and molecular data, the phylogenetic relationships among Pycnopsyche species and species groups were inferred with Bayesian and Maximum Likelihood analyses to …

Top Down Effects And Resource Selection By Coyotes In South Carolina, Alex Jensen

All Dissertations

Top predators play important roles in functioning ecosystems, including regulating the populations of prey species and competing with other predators. However, in the face of global change, many top terrestrial predators have declined in both range and abundance, making room for some smaller predators to expand into new niches. Coyotes (Canis latrans) in North America are a prime example of this – they have rapidly expanded their range in the last 120 years, raising concerns about their impacts on both domestic and wild species. In eastern North America, research has centered around their effects on white-tailed deer ( …

Understanding The Impacts Of Global Change: From Students To Microbes., Kylea Garces

Electronic Theses and Dissertations

Global change is a crucial process, affecting every organism, from the billions of humans on earth, to the billions of microbes in the soil belowground. Evaluating the impacts of the many drastic changes associated with global change is essential in advancing our understanding in how to mitigate these consequences. Alongside the production of basic ecological knowledge associated with these environmental changes, improving education practices to promote science literacy surrounding global change is another step towards a more optimistic future. This dissertation investigates global change from two standpoints: ecologically, where increased atmospheric nitrogen (N) deposition alters plant-fungal endophyte symbiosis, and pedagogically, …

Landscape Genetics Of The Gulf Coast Tick, Amblyomma Maculatum, Sara Simmons Benham

Biological Sciences Theses & Dissertations

Connectivity among populations helps to maintain genetic diversity, population stability, and resilience. The Gulf Coast tick, Amblyomma maculatum, is a vector of the pathogen Rickettsia parkeri. Persistence of tick populations with high rates of R. parkeri infection poses health risks to humans and animals. Mitochondrial haplotypes were characterized by sequencing a fragment of the mitochondrial 16S rRNA gene. A comparative study of A. maculatum and Amblyomma americanum was conducted to identify similar and unique patterns between the species within the same region. Next, I compared A. maculatum sites across three different regions of the United States. This work …

The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Assessing the role geographic isolation and ecological specialization have on phylogeographic patterns contributes to our understanding of the evolutionary history of a species and the processes that erode genetic diversity. I used mitochondrial and nuclear genomic sequences to assess whether habitat isolation has shaped the fine-scale patterns of present-day genetic structure and diversity in two threatened insect species endemic to southern Nevada. Pseudocotalpa giulianii (Coleoptera; Scarabaeidae) is a dune obligate scarab beetle endemic to only two small, isolated sand dunes in Nye County, Nevada, with a usable habitat of less than 4.2 km sq that is impacted by on-going degradation. …

Ecological, Evolutionary, And Temporal Dynamics Of Animal Mortality Events, Simon Patrick Tye

Graduate Theses and Dissertations

Global declines of animal abundances are emblematic of the Anthropocene. Recent animal declines have increasingly involved more frequent and intense die-offs within populations, or mass mortality events (MMEs). These extreme demographic events can lead to rapid changes in biological communities, either by imperiling the affected population or influencing populations remaining within communities. To date, there is still limited information about the effects of predator MMEs on immediate ecological dynamics within communities and rapid evolutionary dynamics within remaining populations that may ensue. Moreover, few approaches exist to predict future occurrences of predator MMEs across broad spatial scales. To address these gaps, …

An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull

Graduate Theses and Dissertations

Orthohantaviruses are a global group of viruses found primarily in rodents, though several viruses have also been found in shrews and moles. Many rodent-borne orthohantaviruses are capable of causing one of several diseases in humans, and the mortality associated with these diseases ranges from < 0.1% - 50% depending on the specific etiological virus. In North and South America, orthohantavirus research was ignited by an outbreak of severe disease in the Four Corners region of the United States in 1993. However, despite the discovery of over 20 orthohantaviruses in the Americas, our understanding of orthohantavirus ecology and virus-host dynamics in this region is still limited, and orthohantavirus surveillance is generally restricted in scope to select regions and small portions of host distributional ranges. In Chapter I, I present a literature review on the current understanding of American rodent-borne orthohantavirus ecology. This review focused on under-studied orthohantaviruses, addressing gaps in knowledge by extrapolating information from well-studied orthohantaviruses, general rodent ecology, and occassionally from Eurasian orthohantavirus-host ecology. There were several key conclusions generated from this review that warrant further research: 1) the large number of putative orthohantaviruses and gaps in orthohantavirus evolution necessitate further surveillance and characterization, 2) orthohantavirus traits differ and are more generalizable based on host taxonomy rather than geography, and 3) orthohantavirus host species are disproportionately found in grasslands and disturbed habitats. In Chapter II, I present a prioritized list of rodent species to target for orthohantavirus surveillance based on predictive modeling using machine learning. Probable orthohantavirus hosts were predicted based on traits of known orthohantavirus hosts using two different types of evidence: RT-PCR and virus isolation. Predicted host distributions were also mapped to identify geographic hotspots to spatially guide future surveillance efforts. In Chapter III, I present a framework for understanding and predicting orthohantavirus traits based on reservoir host phylogeny, as opposed to the traditional geographic dichotomy used to group orthohantaviruses. This framework establishes three distinct orthohantavirus groups: murid-borne orthohantaviruses, arvicoline-borne orthohantaviruses, and non-arvicoline cricetid-borne orthohantaviruses, which differ in several key traits, including the human disease they cause, transmission routes, and virus-host fidelity. In Chapter IV, I compare rodent communities and orthohantavirus prevalence among grassland management regimes. Sites that were periodically burned had high rodent diversity and a high proportion of grassland species. However, rodent seroprevalence for orthohantavirus was also highest in burned sites, representing a trade-off in habitat management outcomes. The high seroprevalence in burned sites is likely due to the robust populations supported by the high quality habitat resulting from prescribed burning. In Chapters V and VI, I describe Ozark virus and Sager Creek virus, two novel orthohantaviruses discovered from specimens collected during Chapter IV. Both chapters report full genome sequences of the respective viruses and compare both nucleotide and protein phylogenies with related orthohantaviruses. Additionally in Chapter VI, I support the genetic analyses with molecular and ecological characterizations, including seasonal fluctuations in host abundance, correlates of prevalence, evidence of virus shedding, and information on host cell susceptibility to Sager Creek virus.

Factors That Affect Home Range Of Timber Rattlesnakes (Crotalus Horridus) In Northwest Arkansas, Bannon Gallaher

Graduate Theses and Dissertations

Conservation of animal populations requires knowledge of their habitat and spatial needs. Quantifying spatial requirements involves the analysis of home range. We examined the effects of sex, body size (SVL), body condition (log mass/log SVL), and year on home range in Timber Rattlesnakes (Crotalus horridus) in Northwest Arkansas. Individual locality data from an ongoing, 22+ year radio-telemetry study in Madison Co., Arkansas were analyzed using both minimum convex polygon (MCP) and Kernel Density Estimates (KDE). Plots of the number of sequential observations versus home range (MCP and KDE) determined that a minimum of 25 locations per individual per active season …

Effects Of Landscape And Yard Features On Mammals In Residential Yards In Northwest Arkansas, Emily Johansson

Graduate Theses and Dissertations

The human footprint is rapidly expanding, and wildlife habitat is continuously being converted to human residential properties. Most wildlife residing in developing areas are displaced to nearby undeveloped areas. However, some animals can coexist with humans and acquire the necessary resources (food, water, shelter) within the human environment. This may be particularly true when development is low intensity, as in suburban yards. Due to the wide variety in how homeowners utilize their yards, they can be considered individually managed “greenspaces.” These yards can provide a range of food (e.g., bird feeders, compost, gardens), water (bird baths and garden ponds), and …

Ecology, Evolution, And Gene Transfer Between Diatoms And Bacteria, Cory B. Gargas

Graduate Theses and Dissertations

Although photosynthetic macro-eukaryotes (i.e., plants) make up the majority of organic biomass on earth, bacteria are the second largest taxonomic group, by biomass. Bacteria are ubiquitous in our environment, living on, and within, man-made surfaces, natural environments, and eukaryotes themselves. The relationship between bacteria and eukaryotes has existed from the very beginning of eukaryotic life in the form of bacterial endosymbioses that resulted in mitochondria and plastids. Other eukaryote–bacteria relationships have evolved since then, ranging from the beneficial (e.g., mutualistic) to harmful (e.g., parasitic or pathogenic). Understanding these eukaryote–bacteria relationships is key to understanding both the evolution of important ecosystem …

Optimal R&D Investment In The Management Of Invasive Species, William Haden Chomphosy, Dale T. Manning, Stephanie A. Shwiff, Stephan Weiler

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive alien species (IAS) threaten world biodiversity, ecosystem services, and economic welfare. While existing literature has characterized the optimal control of an established IAS, it has not considered how research and development (R&D) into new removal methods or technologies can affect management decisions and costs over time. R&D can lower the costs of control in a management plan and creates an intertemporal trade-off between quick but costly control and gradual but cheaper removal over time. In this paper, we develop and solve a continuous time dynamic optimization model to study how investment in R&D influences the optimal control of an …

Local And Regional Landscape Characteristics Driving Habitat Selection By Greater Sage-Grouse Along A Fragmented Range Margin, Aidan T. Beers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In response to ongoing landscape change, wildlife species are likely to respond in varied ways. By studying habitat specialists, we are able to better understand the most likely ways in which the denizens of threatened ecosystems will react to those changes. Among the most threatened ecosystem types in North America are sagebrush ecosystems of the Intermountain West, where one of its most well-known residents, greater sage grouse (hereafter, “sage-grouse), have lost more than 50% of their habitat due to fire, invasive species, climate change, encroachment by coniferous forests and avian predators using it, and human-caused landscape conversion. Sage-grouse rely on …

Fractally Sampling Diversity-Environment Relationships To Understand Plant Assemblage Health Across Spatial Scales, Elizabeth G. Simpson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Humans influence the health of ecosystems and rely on healthy ecosystems to support their livelihoods and well-being. By looking at how the parts of ecosystems interact we can understand and improve ecosystem health. Ecosystem interactions change across spatial scales or different size patches of area. For example, individual organisms interact with each other at small spatial scales, while at large spatial scales, communities of organisms interact with weather conditions. However, many research studies do not look at how ecosystem interactions change across spatial scales. To address this gap in ecological research, I use a fractal sampling design which samples at …

The Barriers To Movement: The Effects Of Anthropogenic Linear Features On The Space-Use Behaviors Of Mule Deer And Pronghorn In Utah, Ronan B. Hart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Human development of structures like roads, fences, and other linear features can make it difficult for animals to move around their environment, affecting their ability to find food and avoid danger. Animal movement and the way they use space comes about from their responses to their surroundings and their choices to balance risk and reward. Because of this, we can understand how roads and fences affect wildlife by studying the way they move around their habitats. In this thesis, I focused on two large herbivores, mule deer and pronghorn, and studied how they use the space within Utah, United States …

Regeneration Of Quaking Aspen And Understory Vegetation Change After Fire Risk Reduction Treatment, Allison M. Trudgeon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quaking aspen (Populus tremuloides Michx.) is a keystone species that, when coexisting with conifers (i.e., seral aspen), often undergoes stand-replacing disturbances to sustain long term vigor. Historically, mixed-to-high severity fire reduced fuels and regenerated aspen, but such disturbances have become less common in recent decades. This has often led to high fuel loading, and many seral aspen stands are at now risk of an unpredictable, high-severity fire, posing a threat to development in the wildland-urban-interface. The lack of a commercial market for aspen, and the risk of conducting prescribed fire, means there are few alternate management options. This has …

Evaluating Methods For Pathogen Spillover Detection And Forecasting In Desert Bighorn Sheep (Ovis Canadensis Nelsoni), Grete E. Wilson-Henjum

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Managers mitigate the effects of disease on wildlife populations by detecting outbreaks and predicting disease transmission. Bighorn sheep (Ovis canadensis) populations face threat from the introduced pathogen Mycoplasma ovipneumoniae (M. ovipneumoniae). In the eastern Mojave Desert, managers detect pathogen outbreaks in desert bighorn (O. c. nelsoni) through aerial population surveys, which produce irregular and coarse population information. Furthermore, managers model the risk of M. ovipneumoniae transmission amongst desert bighorn populations, however these models assume that desert bighorn space use is unchanging across years. Here, I evaluate methods used by managers to detect disease outbreaks …

New Species, Synonymies And Transfers In Neotropical Lamiinae (Coleoptera: Cerambycidae), Larry G. Bezark, Antonio Santos-Silva

Insecta Mundi

Four new species and one new genus of Lamiinae (Coleoptera: Cerambycidae) are described: Nyssodrysilla humeralis new species (Acanthocinini), from Paraguay; Atrypanius schmidi new species (Acan­thocinini), from Paraguay; Chicanatonus hovorei, new genus, new species (Acanthocinini), from Mexico; Euryestola transversa new species (Calliini), from Ecuador. The following new combinations are established: Leiopus convexus Melzer, 1934 is transferred to Hyperplatys Haldeman, 1847; Leiopus floccidus Erichson, 1847 is transferred to Anisopodus White, 1855; Leiopus marcelamonneae Audureau and Demez, 2015 and L. pleuriticus White, 1855 are transferred to Atrypanius Bates, 1864. Leiopus histrionicus Gistel, 1848 is newly synonymized with Eutrypanus dorsalis (Germar, 1823). …

Who To Host: Competition Interactions Between Parasitoid Wasp Species, Jailah Henderson, Becky Hansis-O’Neill

Undergraduate Research Symposium

The availability of resources plays an important role in the survival and fitness of all organisms, one's ability to find and utilize resources can impact interactions between them and their environments. The interaction between organisms for resources can lead to interspecific competition, amongst two different species, or intraspecific competition, amongst the same species. In an experiment to test for competitive interactions between the parasitoid wasp species of N. vitripennis and M. digitata that utilize a fresh fly papua as their host to aid in the reproduction of their offspring. Over a period of time testing for conditions of interspecific and …

Herpetofauna And Tarantula Avoidance: A Missouri Glades Location Survey, Zach Pfeiffer, Becky Hansis-O'Neill, Aimee Dunlap Dr

Undergraduate Research Symposium

Missouri glades are home to a variety of herpetofauna and one species of tarantula: Aphonopelma hentzi (Texas brown tarantula). These animals traverse through their environment very differently. Herpetofauna tend to travel in search of food, while tarantulas are usually restricted to foraging in areas very close to their burrows. Due to this contrast, and because of potential predator-prey relationships, I wanted to see if there was a pattern in the distances between these two groupings. To do this I conducted a location survey to determine how far each individual was from the nearest spider. After analyzing the data, it was …

Extracting And Analyzing Body Pitch Frequency To Test For Mimetic Convergence In Ithomiine Butterflies, Lauren Kim, Angela Robles, Victoria Valenzuela

Pacific Undergraduate Research and Creativity Conference (PURCC)

No abstract provided.