Ecology and Evolutionary Biology Commons^™

The Potential For Dickeya Dianthicola To Be Vectored By Two Common Insect Pests Of Potatoes, Jonas K. Insinga

Electronic Theses and Dissertations

Dickeya dianthicola (Samson) causing blackleg and soft rot was first detected in potatoes grown in Maine in 2014. Previous work has suggested that insects, particularly aphids, may be able to vector bacteria in this genus between plants, but no conclusive work has been done to confirm this theory. In order to determine whether insect-mediated transmission is likely to occur in potato fields, two model potato pests common in Maine were used: the Colorado potato beetle (Leptinotarsa decimlineata Say) and the green peach aphids (Myzus persicae Sulzer). Olfactometry and recruitment experiments evaluated if either insect discriminates between infected and …

A Landscape On The Threshold Of Change: Patterns Of Soil Microbial Ecology Along Dynamic Geomorphic And Hydrologic Features In A Polar Desert, Kelli L. Feeser, David J. Van Horn, Heather N. Buelow, Daniel R. Colman, Theresa A. Mchugh, Jordan G. Okie, Egbert Schwartz, Cristina D. Takacs-Vesbach, Becky A. Ball, Andrew G. Fountain, Michael N. Gooseff, Joseph S. Levy, Maciej K. Obryk

Biology ETDs

The McMurdo Dry Valleys (MDV) of Antarctica are on the threshold of widespread landscape scale change due to increasing temperature and solar radiation and altered hydrology: buried ice is melting, the soil active layer is thickening, thermokarst features are developing along streams, water tracks are expanding, and lake levels are rising. These changes will impact the microbial communities found in each of the affected habitats. The purpose of this work is to first, understand the spatial distribution of soil bacteria in the MDV, specifically investigating the scale-dependent effects of environmental heterogeneity, and second, to perform surveys and coupled experiments to …

Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Impending threats to shrubland ecosystems, posed by climate change, necessitate niche modeling efforts to project vegetation range shifts. However, efforts often remain unguided by individual-scale interspecific plant interactions. The stress gradient hypothesis posits that facilitation should increase in areas of high abiotic stress, only if the individuals are able to ameliorate the surrounding area via functional traits. The Sheep Range of Nevada was used to assess the role of functional traits as predictors of plant association. Larrea tridentata, Coleogyne ramosissima, and Artemisia nova were selected as shrubs with variable life history strategies and ranges in order to identify general patterns …

An Evolving Epigenome That Determines Tissue And Cell Specificity, Renee Louise Sears

Arts & Sciences Electronic Theses and Dissertations

Understanding the mechanisms driving phenotypic variation is a major goal of biology that unifies classical genetics with the emerging fields of genomics and epigenomics. Human and mouse share over 90% of genes and global tissue-specific patterns of expression are maintained between the species. Thus, it is hypothesized that gene expression is influenced through distinctive regulation among species in order to account for the unmistakable phenotypic divergence. DNA methylation, histone modifications, open chromatin patterns, transcription factor binding, and other epigenetic factors are all associated with shaping, maintaining, and repressing regulatory regions which in turn coordinate gene expression. It is vital to …

Trade-Offs Between Survival And Reproduction In Starvation-Selected Drosophila Melanogaster, Tammara Beeghly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evolutionary outcomes are demonstrated by traits that affect an organism’s schedule of reproduction and survival. These life history traits are reflected in an organism’s physiology, development and behavior. Environmental changes, such as availability of nutritional resources, can profoundly affect evolutionary outcomes of individuals and populations. When shortages arise, there will be trade-offs in the allocation of resources, where one trait prevails at the expense of another.

In the laboratory, we can mimic conditions in nature and study the specific effects of the conditions that we re-create. In our case, over 100 generations of Drosophila melanogaster have been selected for starvation …

Mojave Desert Plant Community Long-Term Response To Disturbance, Dominic M. Gentilcore

UNLV Theses, Dissertations, Professional Papers, and Capstones

All vegetation communities have been shaped by disturbances. This dissertation consists of three separate chapters: Blackbrush (Coleogyne ramosissima) natural regeneration in the Great Basin-Mojave Desert Transition Zone on two fires, Long-term Response to Fire in Eastern Mojave Desert semi-arid shrubland communities, and an Annotated Checklist of Gold Butte National Monument in the Mojave-Colorado Plateau Transition Zone. The section on blackbrush natural regeneration was a long-term dataset from two fires in Basin and Range National Monument that burned in 2008 with monitoring events in 2009, 2010, 2011, 2018 and 2019. The monitoring documented some of the strongest post-fire regeneration for the …

Pre-Juvenile Naked Goby (Gobiosoma Bosc) Age And Growth, Annamaria Deitz, Juliana Harding

Honors Theses

Due to the abundance of larval naked gobies, Gobiosoma bosc, within the estuarine ichthyoplankton, it is important to understand their age and growth. Naked gobies are a largely distributed, both geographically and within an estuary, small, benthic fish species. There are 3 pairs of otoliths, calcium carbonate structures within the ear canal, that detect vibrations and record the age of the fish, both daily and annually. Using laboratory-reared gobies of a known age (Tremont et al. 2015), daily signatures on the sagittal otoliths were first validated to be daily, then a growth curve for the wild caught larvae was …

Reconstructing Energy Flow Through Modern And Historical Marine Communities: Insights From Amino Acid Isotope Analysis, Emma A. Elliott Smith

Biology ETDs

The fundamental currency of life is energy. Organisms need energy to grow, to survive and to reproduce. Understanding the acquisition of energy by consumers is thus a foundational aspect of biological research. This is especially important in the modern era, as impacts of ongoing anthropogenic effects will be mediated or amplified through food webs. Here, I explore how isotopic analysis of individual amino acids – a technique new to ecological studies – can be used to trace energy flow through animal communities in modern and ancient time periods. In particular, I focus on kelp forest food webs, which are nearshore …

A Male-Female Genotype-By-Genotype Interaction Mediates The Effect Of Mating On Female Immunity In Decorated Crickets, Kylie J. Hampton

Theses and Dissertations

Sexually antagonistic coevolution should lead to the rapid divergence of male and female genotypes related to the effects of ejaculatory substances on female physiology. Hence, the outcome of mating should depend on an interaction between male and female genotypes. Although mating has been shown to influence female immune responses in diverse insect taxa, a male-female genotype-by-genotype effect on female immunity post-mating remains largely unexplored. Here, we investigate both the effects of mating on female immunity and the potential for a male-by-female genotype interaction on the form and magnitude of this response in decorated crickets. Females from three distinct genotypic backgrounds …

Diet Composition And Mercury Exposure In Bank Swallows (Riparia Riparia) Breeding At Lakeshore And Aggregate Pits, Corrine S. V. Génier

Electronic Thesis and Dissertation Repository

Bank Swallows (Riparia riparia), a threatened species in Ontario, breed primarily in banks at lakeshores and in artificial aggregate pits. Inland pits may be ecological traps for this species, but the relative tradeoffs between these two nesting habitats are unknown. Availability of aquatic emergent insects at lakeshores may have associated nutritional benefits (e.g. Omega-3 fatty acids) and contaminants (e.g. mercury) that can directly influence juvenile growth. This study compares these breeding habitats to evaluate dietary differences as revealed by fatty acids, stable isotopes (δ¹³C, δ¹⁵N, δ²H), fecal DNA barcoding, and mercury. Lakeshore-nesting …

Movements And Behaviors Of Resident And Translocated Northern Map Turtles (Graptemys Geographica) In The Upper Niagara River With Artificial Basking/Nesting Platforms As A Management Strategy, Chelsea L. Moore

Biology Theses

Urbanization and degradation of riparian zones has contributed to the decline of fish and wildlife populations throughout the world. Northern Map Turtles (Graptemys geographica) in the upper Niagara River face similar declines due to shoreline development and the concurrent loss of backwater habitats and terrestrial nesting sites. A project was initiated in which basking/nesting platforms were created, and Northern Map Turtles from a Lake Erie population were translocated into the river. Resident and translocated turtles were tracked using biotelemetry and their habitat use, behaviors, and swimming paths were compared. Translocated turtles exhibited homing behavior and had longer home …

Impacts Of Shoreline Restoration And Source Of Nutrient Enrichment On Macrophytes And Epiphytic Algal Communities, Paige Marie Kleindl

Masters Theses

Macrophytes and their epiphytic algal communities are integral for optimizing littoral ecosystem functioning in lakes. Epiphytic algae’s placement on the plant’s surface can reduce light and nutrient availability (i.e., nitrogen and phosphorus) for the host macrophyte. Macrophyte and epiphytic algal proximity complicates these primary producer group interactions and responses to bioavailable nutrients in the water column or porewater. For example, epiphytic algae may have a competitive advantage over surface water nutrients compared to macrophytes, which may have a competitive advantage over porewater nutrients via root systems.

Muskegon Lake’s industrial history and designation as an Area of Concern prompted shoreline restoration, …

Seasonal Offshore/Inshore Migration Of Round Gobies, Erik Carlson

Theses and Dissertations

Since the invasion of round gobies (Neogobius melanostomus) in Lake Michigan, they have become integrated into both the nearshore and offshore food webs. Round gobies can be found in shallower water (<20 m) during the summer, but they disappear from these depths in early fall. They have been collected, occasionally, offshore in depths greater than 70 m during fall and early spring. These observations and other anecdotal evidence indicate that round goby migrate offshore during the fall and return in the spring. To study this, a large remotely operated vehicle (ROV) was used to conduct video transects offshore at various depths. The offshore sampling showed that round gobies migrated away from nearshore habitat in early October and were almost exclusively found deeper than 20 m by November. The round gobies remained offshore (>30 m) until mid-May, when they began the return to nearshore habitat. The cues to start the offshore and return migrations were not the focus of this project, but the fall offshore migrations coincided with decreasing temperatures nearshore in the fall, and in spring, the offshore movement of the thermal bar. The offshore migration in fall provide an increase in forage opportunity for deep, cold-water predators such as …

The Implementation Of Qpcr Beach Monitoring Methods: Analysis Of A Multi-Lab Validation Study And The Role Of Environmental Parameters On A Comparison Of Colilert And Qpcr Methods, Molly J. Lane

Masters Theses

Public beaches are routinely tested for potentially pathogenic bacteria to protect beachgoers from possible illness. An EPA approved method, Colilert™, used for testing E. coli in recreational water requires 18 – 22 hours before a result is reported but, recreators have already contacted unsafe water before the beach is closed. My study focused on a U.S. EPA proposed qPCR method (Draft Method C) to quantify E. coli in recreational waters that can provide same-day results. In Chapter 2, I examined the calibration procedure used to validate Draft Method C and compared standard curve intercept and slope estimates calculated with a …

Habitat Use Of The Climate-Sensitive Snowshoe Hare (Lepus Americanus) In The Manistee National Forest In Michigan’S Lower Peninsula, Spencer D. West

Masters Theses

Snowshoe hares (Lepus americanus) are a wide-ranging lagomorph that are important forest herbivores and a popular game species throughout their range. Across the southern boundary of their geographic range, snowshoe hares are experiencing population declines and possible extirpation due to increased predation pressure driven by climate change induced camouflage mismatch, competition for forage, degraded and fragmented habitat. One method of reversing the negative trends in snowshoe hare distribution is to increase and improve available hare habitat. A specific habitat analysis for local regions will most effectively advise managers how to target habitat management. I radio-collared 11 snowshoe hares in the …

Genetic Relationships Using Mitochondrial Versus Nuclear Markers: Is The Catfish Rag1 Gene Suitable For Species Differentiation In The Family Pangasiidae?, Huong Thanh Hoang

Graduate Theses and Dissertations

The Mekong River located in Southeast Asia is a global “hotspot” for aquatic biodiversity. It includes an extensive variety of fish species second only to the Amazon River in South America. Recent studies have revealed the impacts of anthropogenic and climate factors on this river system. Such impacts can result in the formation of barriers, which divide a species population and impede gene flow between separated sub-populations. Barriers influence evolutionary trajectories resulting in the generation of geographic variants or subspecies from an ancestral population. Catfish (Teleostei: Siluriformes) are a key species of the Mekong River ecosystem and are an essential …

Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby

Master's Theses

This study examined the effects that water table depth and soil characteristics have on plant species richness and species composition within pitcher plant bogs across seasons. Eight piezometers were installed at random distances to monitor long-term water table depth and pressure fluctuations along a ~710-meter line transect traversing upland and bog habitats. Vegetation sampling quadrats (n=128) were set up near each piezometer. Cover data and water table depths were collected in spring and late summer. Soil samples collected from each treatment group were used to obtain soil texture and nutrient data. The summer collection period yielded a total gdiversity of …

Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding

Animal Science Undergraduate Honors Theses

Belize is a small country, but it is extremely ecologically diverse. Based on the few studies conducted in Belize, the abundance of mammals is low but diversity is high. Particular findings note the number and identity of species differed between four sites in the Maya Mountains of Belize, indicating that a data set from a single site is not representative of the Neotropical region. Insufficient data is available to estimate current species richness of many areas in Belize, including Billy Barquedier National Park (BBNP). The objective of this study was to explore trapping and documentation methods of terrestrial mammals in …

Effects Of Infanticide Risk And Timber Harvest On American Black Bear Space Use, D. Cody Norton

All NMU Master's Theses

Space use is an important aspect of bear ecology that maybe influenced by infanticide risk and timber harvest. I used generalized linear mixed models (GLMM) to determine if female American black bear (Ursus americanus) space use was consistent with avoidance behavior to reduce infanticide risk in the Upper Peninsula of Michigan during the 2009–2011 and 2013–2014 breeding seasons. Females with cubs occupied core areas and home ranges of similar size and relative probability of male use to females without cubs. Additionally, females with cubs did not reduce movements during times of day when male movements were greatest. Female …

Freshwater Turtle Community Composition In Mined Land Strip Pit Lakes And The Effects Of Learned Trap Avoidance On Capture Rates Of Sternotherus Odoratus And Trachemys Scripta, Ethan Craig Hollender

MSU Graduate Theses

Turtles are among the most threatened groups of organisms on the planet and as such are in need of protected habitat where healthy communities can be maintained. The reclamation of land that was formerly the site of surface strip mining provides a matrix of reclaimed terrestrial landscapes rich with lakes and ponds that have the potential to function as such habitat. To determine the suitability of these habitats for turtle communities, I compared the turtle communities of strip pit lakes and natural lakes in southeastern Kansas. Of the seven species of aquatic turtle I encountered, Common Snapping Turtles (Chelydra …

Urban Stream Syndrome And The Presence Of E. Coli In Philadelphia Streams, Eileen Black

HON499 projects

In this experiment, water samples were collected from the Pennypack and Wissahickon Creeks as part of an exploratory study on the presence of microbes, particularly Escherichia coli, in urban streams. Contamination by E. coli may indicate that a creek is polluted and suffering from urban stream syndrome. E. coli was found in both creeks, likely due to their locations near a sewage treatment facility and a farm.

Vines In The Neotropics: Phylogenomics, Biogeography And Systematics In Passion Flowers (Passiflora Subgenus Decaloba Section Decaloba), Serena Acha

Dissertations

With 600 species, Passiflora is a large, morphologically complex and broadly distributed genus in Passifloraceae that represents a major challenge to scientists interested in understanding the evolutionary history of tropical vines. Passiflora has been divided into subgenera, super sections and sections. One of the most enigmatic and species-rich (~120 spp.) groups in Passiflora is section Decaloba, which occurs in the Neotropics and is particularly diverse in Andean montane forests. In this study, we used phylogenomic and population genomic approaches to investigate the evolutionary history, biologeography, species boundaries, and taxonomy of Passiflora section Decaloba. We sampled herbarium specimens, extracted …

A Multi-Scale Investigation Of Habitat Selectivity In Coastal Plain Stream Fishes, Hayley A. Robinson

Honors College Theses

Studying the habitat use of Coastal Plain fishes enables us to develop a deeper understanding of how fishes thrive in this highly variable environment. Based on previous research by Dr. Roberts and his students, Coastal Plain fishes seem to sort into two groups: (1) species selecting stream reaches that continue to flow throughout the summer (i.e., fluvial species [F]) and (2) species occurring in streams that may stop flowing in late summer (i.e., nonfluvial species [NF]). For this study, I took a detailed look at eight of these species, spanning the F-NF gradient, and asked which environmental variables (e.g., water …

Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey Gadek

Biology ETDs

The distribution of life across the Andes mountains reflects historical elevational-range contraction and expansion. Whereas contraction implies specialization, expansion requires overcoming hidden barriers. Three eco-evolutionary phenomena may drive patterns in rates of elevational range evolution: (1) The Dobzhansky-MacArthur Phenomenon (DMP) predicts lower rates of upward expansion with harsher physical conditions, while downward expansion increases with lower diversity; (2) the evolutionary tendency toward specialization predicts contraction increases when ranges are broad; and (3) natural selection for respiratory performance could suppress expansion across mid-elevations due to gene-environment mismatch. We modeled elevational range shifts of Neotropical landbirds. Contrary to the DMP, upward expansion …

Investigating Among-Individual Growth Heterogeneity In Longleaf Pine: Advancing Dendrochronological Approaches, Jamie E. Munn

USF Tampa Graduate Theses and Dissertations

Within a population, individuals frequently differ in the rate at which they grow, and this rate can be impacted by both genetic differences and abiotic factors. Often, dendrochronology is used to elucidate growth trends based on climate or other factors. This dissertation explores new statistical approaches to dendrochronological research.

First, I created a chronology for a population of longleaf pine (Pinus palustris P. Mill.) individuals in a southwest Florida sandhill community. I then used generalized linear mixed models to investigate the effects of fire frequency, year, tree age and size, and elevation on variation in radial growth heterogeneity. I then …

Global Conservation Status And Threat Patterns Of The World’S Most Prominent Forage Fishes (Teleostei, Clupeiformes), Tiffany L. Birge

Biological Sciences Theses & Dissertations

Conserving biodiversity is one of the greatest ethical responsibilities and challenges humans face. Understanding the conservation status of taxonomic groups provides a systematic way to prioritize efforts to combat biodiversity loss. The 405 species within the order Clupeiformes are the herrings, shads, sardines, anchovies, menhadens and relatives that include many of the most important marine forage fishes. These small, schooling fishes are economically, ecologically and culturally significant globally. Despite their contribution to global fisheries and our increasing reliance on these fishes for food and industrial commodities, they are generally poorly known with limited information regarding basic biology and population trends. …

The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a collective prediction among ecologists that climate change will enhance phytoplankton biomass in temperate lakes. Yet there is noteworthy variation in the structure and regulating functions of lakes to make this statement challengeable and, perhaps, inaccurate. To generate a common understanding on the trophic transition of lakes, I examined the interactive effects of climate change and landscape properties on phytoplankton biomass in 12,644 lakes located in relatively intact forested landscapes. Chlorophyll-a (Chl-a) concentration was used as a proxy for phytoplankton biomass. Chl-a concentration was obtained via analyzing Landsat satellite imagery data over a 28-year period (1984-2011) and using …

Systematics Of Carex Section Laxiflorae (Cyperaceae), Jenna Dorey

Dissertations, Theses, and Capstone Projects

Carex, with more than 2100 species, is the most species-rich genus of flowering plants in temperate regions of the world. Members of the family Cyperaceae are colloquially known as sedges, and members of the genus Carex are called “true sedges.” Carex occur on every continent except for Antarctica, they thrive in a panoply of habitats, and are ecologically important as a forage source for wildlife, carbon sequestration, prevention of soil erosion, and providing habitat for fresh water invertebrates. Despite their importance many sedges are still poorly known, such as the woodland sedges in Carex section Laxiflorae, which is …

The Cost Of Protection: Frost Avoidance And Competition In Herbaceous Plants, Frederick Curtis Lubbe

Electronic Thesis and Dissertation Repository

Perennial herbaceous plants in regions that experience winter freezing must survive using belowground structures that can tolerate or avoid frost stress. Soil and plant litter can insulate plant structures from frost exposure, but plants must invest into growth to penetrate through these layers to reach the surface in the spring. The overall goal of my thesis was to test the hypothesis that the protection of overwintering clonal structures by soil or plant litter (frost avoidance) comes at the expense of subsequent reduced growth and competitive ability in absence of freezing stress. I first explored this trade-off with a suite of …

Dynamic Carbon Cycling In Muskegon Lake – A Great Lakes Estuary, Katie Lynn Knapp

Masters Theses

Ecosystem metabolism is the coupling of carbon and oxygen through photosynthesis and respiration. Gross primary production (GPP) is the carbon fixation by photosynthesis, ecosystem respiration (R) is carbon remineralization by bacterial and plankton respiration, and net ecosystem production (NEP) is the balance. Metabolism estimates determine if ecosystem is a sink or source of carbon to the atmosphere. When a lake has a positive NEP, or the GPP:R ratio is greater than 1, it is considered autotrophic and less carbon is being lost to the atmosphere than taken in, whereas if NEP is negative (GPP:R-1d^-1, respectively and the BOD …