Other Ecology and Evolutionary Biology Commons^™

Science, Community, And Culture: A Holistic Approach To Ecological Research And Education, Laura Whipple

All NMU Master's Theses

Global biodiversity has declined at an alarming rate over the past century as a result of many complex human-induced environmental changes. Standardized surveys have historically been used to identify drivers of species declines, but such studies are often resource-intensive, resulting in significant spatial and temporal data gaps when researchers lack the resources necessary to maintain such studies. One promising solution for overcoming gaps in standardized studies is the integration of species observations by community members (e.g., community science). Along with improving modeling techniques to address biodiversity declines, the education of future ecologists on the importance of Indigenous ecological knowledge, robust …

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.

Exploring Host-Parasite Interactions In The Euhaplorchis Californiensis-Fundulus Parvipinnis System, Bennett J. Perry

All HCAS Student Capstones, Theses, and Dissertations

Parasites with complex life-cycles may alter their intermediate host’s phenotype to increase the chance of successful transmission to their next host. This parasite-induced host modification often occurs in the form of behavioral changes, such as increased frequency of irregular locomotor behaviors (e.g., conspicuous behaviors), particularly in systems where the parasite is transmitted trophically through a predation event. However, most empirical evidence of host behavioral modification by parasites comes from a few model host-parasite systems and are frequently studied following a stressor (e.g., simulated predator attack). One host species studied is the California killifish Fundulus parvipinnis, which is infected by …

The Bellarmine Bee Bed: Organizing A Native Plant Garden Using Feedback From The Local Community, Kate Moran

Undergraduate Theses

Animal pollinators are the cornerstone of healthy ecosystems. Their survival is essential for the persistence of entire food chains: from the flowers they cross-pollinate directly, to the animals who depend on those plants for nutrition. The establishment of pollinator gardens—particularly ones that consist of native plants—is an effective way to enhance their biodiversity, abundance, and well-being.

The main goal of this thesis is to construct a pollinator garden that maximizes the benefits for animal pollinators using feedback from local gardeners. A survey was used to gather information about the popularity and preferences of 40 flowering plants, and after analyzing the …

Evaluation Of Reproductive Phenology, Space Use, And Ecology Of The Eastern Wild Turkey (Meleagris Gallopavo Silvestris) In West-Central Louisiana, Chad Argabright

LSU Master's Theses

Nest site selection is a driving demographic force behind eastern wild turkey (Meleagris gallopavo silvestris) populations. However, previous research was likely not focused on the actual time of nest site selection, considering that nest site selection is likely only able to occur on the day of the first egg being laid. My objective was to determine if selection for any vegetation characteristics was occurring on the first day of laying. I estimated the path taken from the roost to the nest on the first day of egg laying (i.e., laying path) using GPS data collected from 164 unique …

Adaptive Plasticity Of Coloration In Response To Environmental Change, Karissa Coffield

Scholars Week

When rapid environmental changes occur, different selective forces can create phenotypic trade-offs in which a trait can provide fitness benefits or costs under different environmental conditions. Amphibians are particularly vulnerable to environmental change, and previous research has revealed that some species will plastically respond to variation in temperature and ultra-violet radiation (UVR) by altering their coloration. Divergent selection on coloration may change with elevation and climate induced shifts in temperature because high temperatures are likely to result in lighter color morphs but as elevation increases, UVR exposure increases leading to the prediction that darker color morphs will be more common. …

Adaptive Plasticity Of Coloration In Response To Environmental Change, Karissa Coffield

Scholars Week

When rapid environmental changes occur, different selective forces can create phenotypic trade-offs in which a trait can provide fitness benefits or costs under different environmental conditions. Amphibians are particularly vulnerable to environmental change, and previous research has revealed that some species will plastically respond to variation in temperature and ultra-violet radiation (UVR) by altering their coloration. Divergent selection on coloration may change with elevation and climate induced shifts in temperature because high temperatures are likely to result in lighter color morphs but as elevation increases, UVR exposure increases leading to the prediction that darker color morphs will be more common. …

Senesced Leaves Of An Invasive Species (Lonicera Maackii) Alter Community Composition And Ecosystem Function In Experimental Wetlands, Cy Mott

2023 Midwest Ecology & Evolution Conference

Secondary compounds produced by terrestrial invasive plants can cross terrestrial-aquatic boundaries via senesced leaves, leading to altered patterns of aquatic biodiversity and ecosystem functioning. Prior attempts to examine the impacts of invasive leaves on wetland communities have primarily employed the use of leaf leachates and focal taxa inhabiting relatively low trophic positions, and additional studies are needed to examine impacts on higher-order consumers and potential additive/synergistic effects of leachates and leaf decomposition. Using cattle-tank mesocosms across multiple experiments, we observed that the addition of senescent leaves of Amur Honeysuckle (Lonicera maackii) to native leaves resulted in mass mortality …

The Effects Of Imposed Drought And Nutrient Availability On Soil Microbial Biomass And Enzyme Activity In A Long-Term Restored Grassland, Ashley A. Wojciechowski

2023 Midwest Ecology & Evolution Conference

Restoring agricultural lands back to grassland aims to reverse many negative impacts of agriculture on the ecosystem including nutrient export from soil and depletion of soil carbon. Planting prairie on agricultural soil promotes recovery of soil microbial biomass and their enzymes, which create demand for nitrogen by microbes to reduce the rate of nutrient cycling and loss. A complicating factor in the development of a restored grassland the influence of several anthropogenic global changes including increasing frequency of drought and nutrient enrichment. Drought has been found to negatively affect microbial biomass, soil enzyme activity and nutrient cycling. Nutrient (often N) …

Effects Of Extra-Pair Paternity On Provisioning Effort And Nest Defense In Male House Wrens (Troglodytes Aedon), Avery Dart

2023 Midwest Ecology & Evolution Conference

Some animals form socially monogamous pair bonds in which a male and female mate and raise young together. However, individuals within a socially monogamous pair bond may still mate with other individuals; this mating is defined as extra-pair mating (EPM). Extra-pair paternity (EPP) occurs when offspring arise from EPM. In wild birds, EPM is approximated by EPP. Males benefit from EPP by siring additional offspring without any investment aside from sperm, but the benefits of EPM for females are less clear. Females may gain fertility assurance, access to better foraging grounds, and nest protection from males, as males are incentivized …

Adaptive Plasticity Of Coloration In Response To Environmental Change, Karissa Coffield

2023 Midwest Ecology & Evolution Conference

When rapid environmental changes occur, different selective forces can create phenotypic trade-offs in which a trait can provide fitness benefits or costs under different environmental conditions. Amphibians are particularly vulnerable to environmental change, and previous research has revealed that some species will plastically respond to variation in temperature and ultra-violet radiation (UVR) by altering their coloration. Divergent selection on coloration may change with elevation and climate induced shifts in temperature because high temperatures are likely to result in lighter color morphs but as elevation increases, UVR exposure increases leading to the prediction that darker color morphs will be more common. …

Endophytic Fungi And Their Competitive Hierarchy And Effects Of Changing Environmental Nitrogen., Haley G. Bryant, Kylea R. Garces

2023 Midwest Ecology & Evolution Conference

Endophytes are fungi that live symbiotically within the roots of plants. These fungi can serve different functions within the roots, and are thought to form a competitive hierarchy that allows them to coexist. It is not well established how specific species act within this endophytic dynamic, especially with each other. This experiment looked to better understand these relationships through Grime’s C-S-R model; growing the extracted fungal species in different treatments: control, stress, low nitrogen, high nitrogen, and comparing each growth rate and biomass over a two-week period. The species looked at in this study were extracted from dominant dune-building grass …

Late Cretaceous Marine Vertebrates From The Tarrant Formation, Tarrant County, Texas U.S.A, Aaron Johnson, Kenshu Shimada

2023 Midwest Ecology & Evolution Conference

The Tarrant Formation (middle Cenomanian: ca. 96 million years ago) is a stratigraphic member of the Upper Cretaceous Eagle Ford Group in Texas, U.S.A., and consists of calcareous sandstone formed near the East Texas Embayment of the Late Cretaceous Western Interior Seaway, an epicontinental seaway in North America. We examined vertebrate fossils from the Tarrant Formation based on specimens collected through surface collecting and bulk sampling from three localities in Tarrant County, Texas, including the type locality of a pachyrhizodontid fish, Polcynichthys lloydhilli. Our preliminary examination shows that the fossil fauna includes shark species such as Ptychodus anonymous, Archaeolamna sp., …

Pollinators And Flowering Resources In Louisville Urban Green Spaces, Sarah Hobbs

2023 Midwest Ecology & Evolution Conference

Urban Greenspaces can appear in many different forms such as parks, urban orchards, and community gardens. These spaces provide important ecosystem services such as enhanced biodiversity, improved soil health, and increased carbon sequestration. Greenspaces such as parks and community gardens have been relatively well studied in the last few decades compared to urban orchards, despite the multitude of ecosystem services that can be provided or enhanced by these orchards. We hypothesize that urban orchards will provide the optimal conditions for pollinator communities because urban orchards normally have the greatest variety of vegetation and flowering resources, which is positively correlated with …

Herbarium Records Reveal Sex-Specific Effects Of Climate Warming On Phenology Of Fragaria Virginiana, Ethan R. Richardson

2023 Midwest Ecology & Evolution Conference

Plant populations tend to be hermaphroditic, but in some cases can diverge into a dioecious sexual system, or one that possesses both male and female members. Prior studies show a correlation between sex systems evolution such as these and ecological variables. These variables impose challenges on plants' ability to propagate and in a dioecious population, males and females have been seen to respond differently to different environmental contexts. What is still being studied is the degree to which biogeography contributes to the sexual differentiation of dioecious species. While evidence supports the idea of a latitudinal gradient contributing to sexual differentiation, …

How Accurately Structure Can Identify Hybrids When Comparing Different Numbers Of Species And Marker Types And Numbers, Chloe Hendrikse

2023 Midwest Ecology & Evolution Conference

Hybridization is a common problem in conservation. It can be difficult to identify hybrid individuals but doing so is often necessary in order to make conservation recommendations. For example, botanical gardens and seed banks want to identify if individuals are hybrids of two or more species to determine if offspring could be used for conservation or restoration, and to analyze the risk of possible extinction via introgression. Our project looks at how well the program STRUCTURE can detect and cluster hybrids, their parent species, and other pure species, which we created using simulations. We build on past studies, which typically …

Air Pollution Is Associated With Increased Stress In Urban Songbirds, Reagan Earlywine

2023 Midwest Ecology & Evolution Conference

Air pollution has been suggested to be a major driver of decline in native bird populations. Understanding how air pollution affects avian physiology and how air pollution exposure may be reduced may help develop effective conservation solutions. Here we tested whether elevated air pollution exposure was associated with increased physiological stress response in free-living urban American robins, and whether urban vegetation mitigated this effect. Specifically, we asked whether the concentration of the stress-related glucocorticoid hormone corticosterone was predicted by exposure to two metrics of air pollution: nitrogen dioxide (NO₂) and ultrafine particulates (UFPs); and two metrics of green …

Effect Of Functional Trait Variation On Bee Body Temperature, Gabriella A. Muller

2023 Midwest Ecology & Evolution Conference

Bees are both ecologically and economically important pollinators for maintaining agricultural production and the health of many diverse ecosystems. As our world continues to change, bee diversity and population numbers are declining due to increasing temperatures. Functional traits such as body size and coloration can mediate the effects of such harsh thermal conditions on insect performance. Specifically, bee body size can significantly impact thermal parameters, with larger bees gaining and losing heat more slowly than smaller bees due to higher surface area to volume ratios. To obtain a better understanding of these relationships, we studied the variation in body temperature …

Quantifying The Relationship Between Arbuscular Mycorrhizal Fungi And A Native And Invasive Thistle, Nicole Baker, Lucia Vera, Ian Rosales

2023 Midwest Ecology & Evolution Conference

Arbuscular mycorrhizal fungi (AMF) associate with 80% of vascular plant roots and are an important part of nutrient exchange. Our research quantified the relationship between (AMF) and native Pasture Thistle (Cirsium discolor) and invasive Canada Thistle (Cirsium arvense). We hypothesized that Pasture Thistle would have a stronger relationship with AMF than Canada Thistle because of the degraded mutualism hypothesis, which states that invasive species have reduced relationships with AMF. For our experiment, we grew inoculated and non-inoculated plants at 10 different levels of soil phosphorus concentrations. Pasture Thistle and Canada Thistle were both facultatively dependent upon …

An Optimal Patch Use Model For Nitrogen Foraging In Arbuscular Mycorrhizal Fungi, Xin Lin

2023 Midwest Ecology & Evolution Conference

Optimal Foraging Theory has been widely used to study animal foraging behaviors, but has seldom been applied to symbiotic microbes like arbuscular mycorrhizal (AM) fungi. To date we know little about how AM fungi make decisions to forage in different nutrient patches. To help address this gap we here apply Optimal Foraging Theory to understand how AM fungi forage for nitrogen. We focus on nitrogen because AM fungi need more nitrogen than their plant hosts and soil nitrogen availability can shift the relationship between AM fungi and their hosts from mutualism to parasitism. We present a stochastic dynamic programming model …