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Hidden Diversity In Aquatic Habitats: Lessons From Cryptic Species In Microscopic Invertebrates (Rotifera), Azar Kordbacheh

Open Access Theses & Dissertations

Speciation is a continuous and adaptive process by which lineages are diverged into multiple groups, and species are the product of this process. Taxonomy is the study of relationship between organisms, classifying and naming them, and one of the taxonomical challenges is delimiting species boundaries. Species delimitation can be controversial because biologists do not agree on species concepts and approaches for defining species boundaries. One of the well-known species concepts is the Biological Species Concept that requires studying reproductive barriers among populations. Investigating strength of reproductive isolation among populations is not always practical in the wild. Therefore, many biologists have …

Chironomidae (Diptera) Community Structure In Lakes Of Contrasting Morphometry, Landscape Position, And Water Chemistry, Conrad Stanley Zack

Master's Theses

Chironomidae (Diptera) surface-floating pupal exuviae were collected monthly during the ice-free season in 2010-2011 from six lakes in the North Temperate Lakes Long-Term Ecological Research site in northern Wisconsin. The goal of this study was to determine whether chironomid community structure reflected differences in lake morphometry (i.e., depth, area, shoreline development, etc.), water chemistry, and/or landscape position (i.e., elevation). Forty-six genera were identified from four subfamilies: Chironominae (57%), Orthocladiinae (28%), Tanypodinae (11%), and Diamesinae (4%). Tanytarsus, Ablabesmyia, and Psectrocladius were found in all six study lakes; whereas certain genera, such as Omisus, Protanypus, and Epoicocladius were each observed in only …

Identification Of Taxonomic And Functional Ichthyofaunal Zones Within The James River Basin, Virginia, Joseph L. Noel

Theses and Dissertations

Environmental gradients structure ichthyofaunal communities longitudinally along river networks via the selective filtering of species’ traits. In many instances, these environmental influences have created distinct zones of co-occurring fish species. Zonation studies have most often been conducted with taxonomic data (species x site matrices), but the increasing availability of functional trait data creates an opportunity to build more rigorous understanding of species’ co-occurrence patterns. Notably, zonation studies that use taxonomic data may not reveal the same patterns as studies based on trait data. In this study, we tested for distinct ichthyofaunal zonation in James River Basin, VA using a combination …

The Role Of Vegetation-Topographic Interactions In A Barrier Island System: Island Migration In A Changing Climate, Benjamin Nettleton

Theses and Dissertations

Islands have been characterized based on vegetation and topography as exhibiting different disturbance regimes - reinforcing or resisting. This study had two objectives: quantify barrier island upland migration and vegetation cover change over 32 years (1984-2016), and assess tolerance of two prevalent dune grass species, A. breviligulata, and S. patens to sand burial. Using Landsat imagery from the Virginia Coast Reserve, islands were categorized within the disturbance resistance/reinforcing framework based on dune elevation. Resistant areas were associated with woody cover and low marsh to upland migration while reinforcing areas had low vegetation cover and high rates of migration. System-wide, …

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind

Theses and Dissertations

Species of trees inhabit diverse and heterogeneous environments, and often play important ecological roles in such communities. As a result of their vast ecological breadth, trees have become adapted to various environmental pressures. In this dissertation I examine various environmental factors that drive evolutionary dynamics in threePinusspecies in California and Nevada, USA. In chapter two, I assess the role of management influence of thinning, fire, and their interaction on fine-scale gene flow within fire-suppressed populations of Pinus lambertiana, a historically dominant and ecologically important member of mixed-conifer forests of the Sierra Nevada, California. Here, I find evidence …

Migratory Patterns And Population Genetic Structure In A Declining Wetland-Dependent Songbird, Matthew G. Desaix

Theses and Dissertations

Understanding migratory connectivity is essential for assessing the drivers behind population dynamics and for implementing effective management in migratory species. Genetic markers provide a means to describe migratory connectivity, as well as incorporate population genetic analyses, however genetic markers can be uninformative for species with weak genetic structure. In this study, we evaluate range-wide population genetic structure and migratory connectivity in the prothonotary warbler, Protonotaria citrea, a wetland-dependent neotropical migratory songbird, using high-resolution genetic markers. We reveal regional genetic structure between sampling sites in the Mississippi River Valley and the Atlantic Seaboard with overall weak genetic differentiation among populations …

Riparian Vegetation And The Soil Seed Bank Five Years After Dam Removal On The Elwha River, Washington, Cody C. Thomas

EWU Masters Thesis Collection

Damming of rivers is widespread and can profoundly impact riparian areas by altering the fluvial processes that drive riparian vegetation communities. Dam removal may reverse these effects; however, very few studies have examined the response of riparian vegetation to large dam removal and associated disturbances, such as the release of sediment. Understanding how dam removal impacts downstream riparian vegetation is crucial as dam removal becomes more common. The Elwha River, Washington, is the location of the largest dam removals to date and provides an unprecedented opportunity to explore questions related to dam removal and riparian vegetation. The objectives of this …

Monitoring The Influx Of Marine Derived Nitrogen And Characterizing Soil Food Webs Of Riparian Zones Of The Elwha River Watershed, Wa, Usa., Wendal R.H. Kane

EWU Masters Thesis Collection

Nitrogen is often the most limiting nutrient to productivity in terrestrial ecosystems, and can have large effects on ecosystem processes. Two sources of nitrogen to Pacific Northwest riparian areas are marine derived nitrogen (MDN) via anadromous pacific salmon and symbiotic nitrogen fixation via Alnus rubra. The recent removal of two large dams on the Elwha River, WA, opened up ~60 km of previously inaccessible river habitat for pacific salmon. I used naturally abundant stable nitrogen isotopes (denoted as ‰ δ15N) to establish baseline data to monitor the influx of MDN to riparian zones of Elwha River tributaries, post dam removal. …

Evolution Belief Trends, Jamie Jensen

ScholarsArchive Data

This is the essay code frequencies along with the raw survey data for both Cohort 1 and Cohort 2 for the following paper:

Bradshaw, WS, Phillips, AJ, Bybee, SM, Gill, RA, Peck, SL, Jensen, JL. 2018. A longitudinal study of attitudes toward evolution among Mormon undergraduates. PLOSONE.

Researchers, Not Dogs, Lack Control In An Experiment On Jealousy, Jennifer Vonk

Animal Sentience

Cook and colleagues (2018) have developed a clever method to measure fMRI in awake dogs in response to a number of interesting stimuli. As a result, they are able to determine neural correlates of observable behavior. They report that dogs may experience something akin to jealousy because they show greater amygdala activation in response to food being given to a fake dog versus food being placed in a bucket. However, several critical controls are missing which prevent the authors from being able to speak of jealousy.

Dogs Aren’T Jealous – They Are Just Asking For Accurate Information, Karen L. Overall

Animal Sentience

Awake fMRI offers us a unique opportunity to view and understand how dogs see the world and use the information in it. Given the limitations of behavioral assays and the small sample sizes inherent in these studies, labeling of patterns of canine behaviors using pop psychology terms may actually interfere with our understanding of canine brains and obscure for us a more parsimonious but exciting interpretation of canine behavior. We should use this window into how dogs think wisely.

Situating The Study Of Jealousy In The Context Of Social Relationships, Christine E. Webb, Frans B. M. De Waal

Animal Sentience

Whereas the feelings of other beings are private and may always remain so, emotions are simultaneously manifested in behavior, physiology, and other observables. Nonetheless, uncertainty about whether emotions can be studied adequately across species has promoted skepticism about their very presence in other parts of the animal kingdom. Studying social emotions like jealousy in the context of the social relationships in which they arise, as has been done in the case of animal empathy, may help dispel this skepticism. Empathy in other species came to be accepted partly because of the behavioral similarities between its expression in nonhuman animals and …

The Degeneracy Of Behavior And The Rise Of Neuroimaging To Measure Affective States In Dogs, Peter F. Cook, Gregory S. Berns

Animal Sentience

It is gratifying and significant that so many scientists from diverse fields are arguing in-depth regarding a particularly complex set of social emotions in a non-human animal. Emotions play a fundamental role in decision making and information processing. Neuroimaging is important in understanding the cognitive and emotional worlds of non-human animals and can help measure covert emotions lacking clear behavioral correlates. Various experimental approaches could clarify the relative importance of attachment and aggression in jealousy and whether the phenomenon we measured is more akin to human envy or jealousy. Reverse inference from amygdala activation is probably justified because behavior is …

Is Superiority A Necessary Aspect Of Cruelty?, William H. Edmondson

Animal Sentience

Chapman & Huffman argue that humans inflict cruelty without apparent concern because of their categorization of the victims as inferior. The supposed inferiority of non-human animals can be argued against on the basis of documentation and analysis of behaviour. Humans continue to inflict cruelty on their own and other species. It is not obvious that a sense of superiority is a necessary aspect of cruel behaviour. Nor is it obvious that further enlightenment regarding the cognitive status of non-humans will diminish cruelty.

Human Superiority?, Bernard Rollin

Animal Sentience

Like Charles Darwin and George Romanes, I am quite willing to use anecdotal information as a source of knowledge about animal behavior. There are many more people observing nonhuman animals than there are people conducting controlled experiments, and we can thereby learn that behaviors we think are unique to humans are shared by other animals. From a strictly biological point of view, it makes no sense to speak of “human superiority.” One species of animal can be superior to another only in terms of survival and niche occupation. As moral concern for animals increases across the world, claims of human …

Searching The Internet To Estimate Deer Population Trends In The U.S., California, And Connecticut, G. Webb

Faculty Research, Scholarly, and Creative Activity

Information for decision making may be publicly available, but costly to obtain. As an experiment in environmental scanning, the internet was searched on a daily basis over several years to collect information and provide analysis related to decisions on deer management. The process discovered that, contrary to common assumptions, the U.S. deer population has apparently been falling since about the year 2000 based on analysis of available state data that had not been aggregated. In some cases, state population estimates were created using standard procedures on available data. Results indicate that differences in survey methods appear to be relatively constant …

A Comparison Of Two Methods Of Quantifying Mating Success In Low Density Gypsy Moth (Lymantria Dispar) Populations, Alexandra Barry, Hannah Byrne, Derek M. Johnson

UROP Posters

The gypsy moth (Lymantria dispar) is a defoliating pest native to Europe and invasive to North America. The gypsy moth is subject to depressed mating success in low density populations, which may restrict spread of the forest pest. Research focusing on gypsy moth density as it relates to mating behavior has often used counts of males caught in pheromone-baited delta traps as a proxy to estimate the probability of female mating success. The purpose of this project was to determine whether pheromone trap counts provide accurate estimates of female mating success probability, by comparing data gathered from pheromone-baited …

Parasitaemia Data And Molecular Characterization Of Haemoproteus Catharti From New World Vultures (Cathartidae) Reveals A Novel Clade Of Haemosporida, Michael J. Yabsley, Ralph E.T. Vanstreels, Ellen S. Martinsen, Alexandra G. Wickson, Amanda E. Holland, Sonia M. Hernandez, Alec T. Thompson, Susan L. Perkins, Christopher A. Lawrence Bryan, Christopher A. Cleveland, Emily Jolly, Justin D. Brown, Dave Mcruer, Shannon Behmke, James C. Beasley

Faculty & Staff Scholarship

Background: New World vultures (Cathartiformes: Cathartidae) are obligate scavengers comprised of seven species in five genera throughout the Americas. Of these, turkey vultures (Cathartes aura) and black vultures (Coragyps atratus) are the most widespread and, although ecologically similar, have evolved differences in morphology, physiology, and behaviour. Three species of haemosporidians have been reported in New World vultures to date: Haemoproteus catharti, Leucocytozoon toddi and Plasmodium elongatum, although few studies have investigated haemosporidian parasites in this important group of species. In this study, morphological and molecular methods were used to investi- gate the epidemiology and molecular biology of haemosporidian parasites of …

"Squeezed Between The Gunshots And The Gentrifiers”: Urban Agriculture In Philadelphia's Kensington Neighborhood, Arianna Hall-Reinhard

Graduate Theses, Dissertations, and Problem Reports (ETD)

Urban agriculture (UA) is part of the broader alternative food movement and a potential avenue through which to “do” food justice work. UA projects in the urban Global North are frequently motivated by social and food justice goals. Despite these guiding ideals, UA projects in America are rife with internal contradictions, including those related to racial inequalities, complex gentrification dynamics, and funding realities. In this paper, I employ the conceptual frameworks of food justice and urban political ecology to consider how gentrification and UA project funding structures affect five specific UA projects in Philadelphia’s Kensington neighborhood. While the loss of …

Sentient Plants? Nervous Minds?, Arthur S. Reber

Animal Sentience

The commentaries by Calvo (2018) and Mallatt & Feinberg (2017) on my 2016 target branch out from a common conceptual node like forks in a road. Calvo criticizes me for not acknowledging that plants too are likely to be sentient and claims I have fallen into the kind of category error of which I accuse others ─ a zoocentric bias that fails to grant consciousness to flora. Mallatt & Feinberg maintain that I've gone too far in granting sentience to any species that lacks a nervous system. Calvo makes some good points but there are other issues concerning plant sentience …

Predictors Of Fish Assemblage Structure And Dynamics In Atlantic Coastal Plain Streams, Rebecca Scott

College of Graduate Studies: Theses & Dissertations

Effective management of freshwater fishes requires a mechanistic understanding of the drivers of assemblage composition; in other words, what determines who is where and when. Stream fish assemblages are potentially influenced by environmental factors that act on multiple spatiotemporal scales, but the relative influence of these drivers may vary between geophysically distinct regions. This study sought to determine the patterns and drivers of fish taxonomic and functional assemblage composition in the coastal plain, a region possessing unique hydrologies, faunas, and physiochemical conditions. I addressed this goal using two complementary chapters, both of which utilized environmental and biotic data collected from …

Comparison Of Three Benthic Macroinvertebrate Passive Sampling Devices For Non-Wadeable Streams, Kelsey A. Laymon

College of Graduate Studies: Theses & Dissertations

Rivers and streams provide essential ecosystem services to the degree that the monitoring and maintenance of these systems becomes imperative. Biomonitoring provides managers and policymakers with the tools to make informed decisions, and macroinvertebrates are often the object of biomonitoring because they are ubiquitous in most systems and are known to be good indicators of water quality. However, methods for sampling macroinvertebrates in non-wadeable streams (i.e., large rivers) have not been standardized across states and regions and an established method for macroinvertebrate biomonitoring in large rivers of Georgia is not currently available. My study compared macroinvertebrates collected with three types …

Characterizing The Complex Relationship Between The Brown Widow Spider And Its Bacterial Endosymbiont, Wolbachia, Emily Knight

College of Graduate Studies: Theses & Dissertations

The brown widow spider, Latrodectus geometricus (C. L. Koch 1841), has been found to harbor the maternally inherited bacterial endosymbiont Wolbachia pipientis (Hertig and Wolbach 1924), but endosymbiont infection frequency varies widely among Southeastern US populations. Wolbachia is known to manipulate the reproduction of its hosts through male feminization, parthenogenesis, male killing, and cytoplasmic incompatibility. In brown widows, Wolbachia does not alter sex ratios, but any other effects the symbiont has on the spider are unknown. In my first chapter, I assess if there is linkage between Wolbachia infection and maternally inherited mitochondrial DNA (mtDNA) in three brown widow populations. …

Foraging Ecology Of A Winter Bird Community In Southeastern Georgia, Rachel E. Mowbray

College of Graduate Studies: Theses & Dissertations

Classical views on community structure emphasized deterministic processes and the importance of competition in shaping communities. However, the processes responsible for shaping avian communities remain controversial. Attempts to understand distributions and abundances of species are complicated by the fact that birds are highly mobile. Many species migrate biannually between summer breeding grounds and wintering grounds. The goal of this study was to test four hypotheses that attempt to explain how migratory species integrate into resident assemblages of birds (Empty-Niche Hypothesis, Competitive-Exclusion Hypothesis, Niche-Partitioning Hypothesis, and Generalist-Migrant Hypothesis). I collected data on birds foraging during the winter of 2017-2018 in Magnolia …

Relationships Between Factors Influencing Biofilm Formation And Pathogen Retention In Complex Rhizosphere Microbial Communities, Aaron Coristine

Theses and Dissertations (Comprehensive)

Riparian wetlands are unique habitats facilitating all forms of life. The riverbanks of these environments provide ideal conditions for bacteria, plants, and higher organisms. Of particular interest to this research was the variation in microbial community structure at high, intermediate and poor water quality impacted areas. Assessing the capabilities of plants to retain microbial pathogens was identified. Root systems and corresponding soil are ideal locations for bacterial deposition, resulting in attachment at these areas. Biofilm production in these regions is important for long-term establishment, leading to persistence and potential naturalization. Opportunistic pathogens originating from mammalian fecal matter are introduced into …

Spatial Modelling And Wildlife Health Surveillance: A Case Study Of White Nose Syndrome In Ontario, Lauren Yee

Theses and Dissertations (Comprehensive)

Wildlife data is often limited by survey effort, small sample sizes, and spatial biases associated with collection and missing data. These factors can create unique challenges from a surveillance perspective when trying to extract spatial patterns of habitat suitability and disease distributions for conservation and management purposes. This thesis examined data quality from a wildlife health database in the context of spatial analysis of wildlife disease. Spatial analysis of the data to predict habitat suitability of bats and white nose syndrome afflicted bats was examined by using the MaxEnt modelling method. Methods to reduce spatial bias were examined and specific …

Near-Surface Permafrost Ground Ice Characteristics And Ecological And Physical Drivers Of Transient Layer Ice Content In Discontinuous Permafrost, Jason Paul

Theses and Dissertations (Comprehensive)

Accelerated climate warming in northern regions is causing permafrost degradation, leading to the reduction of the areal extent of permafrost. Permafrost is the foundation for many northern ecosystems and communities, so its thaw can have important ecological and societal consequences. Thaw of ice-rich permafrost can cause subsidence of the ground surface proportional to excess ice content. Terrain settlement can cause ponding or damage to infrastructure. Following a surface disturbance that removes much of the vegetation cover, a shift in the ground thermal regime can cause an increase in active layer thickness and rapid thaw of the top portion of permafrost. …

Contemporary Fire Regimes Of The Arid Carnarvon Basin Region Of Western Australia, Megan Ladbrook, Eddie Van Etten, William D. Stock

Research outputs 2014 to 2021

This study investigates the fire regime for the arid Carnarvon Basin region of Western Australia using remotely sensed imagery. A fire history database was constructed from satellite images to characterise the general fire regime and determine any effect of vegetation types and pre-fire weather and climate. The study area was divided into two sections (northern and southern) due to their inherently different vegetation and climate. A total of 23.8% (15,646 km2) of the study area was burnt during the 39-year study period. Heathland vegetation (54%) burnt the most extensively in the southern study area, and hummock grasslands (68%) in the …

Organic Carbon Sequestration And Storage In Vegetated Coastal Habitats Along The Western Coast Of The Arabian Gulf, M Cusack, V Saderne, A Arias-Ortiz, Pere Masque, P K. Krishnakumar, L Rabaoui, M A. Qusem, P Prihartato, R A. Loughland, A A. Elyas, C M. Duarte

Research outputs 2014 to 2021

Certain coastal ecosystems such as mangrove, saltmarsh and seagrass habitats have been identified as significant natural carbon sinks, through the sequestration and storage of carbon in their biomass and sediments, collectively known as 'blue carbon' ecosystems. These ecosystems can often thrive in extreme environments where terrestrial systems otherwise survive at the limit of their existence, such as in arid and desert regions of the globe. To further our understanding of the capability of blue carbon ecosystems to sequester and store carbon in such extreme climates, we measured carbon sediment stocks in 25 sites along the Western Arabian Gulf coast. While …

Tracing Water Masses With 129i And 236u In The Subpolar North Atlantic Along The Geotraces Ga01 Section, Maxi Castrillijo, Núria Casacuberta, Marcus Christl, Christoph Vockenhuber, Hans A. Synall, Maribel I. García-Ibáñez, Pascale Lherminier, Géraldine Sarthou, Jordi García-Orellana, Pere Masqué

Research outputs 2014 to 2021

Pathways and timescales of water mass transport in the subpolar North Atlantic Ocean (SPNA) have been investigated by many studies due to their importance for the meridional overturning circulation and thus for the global ocean. In this sense, observational data on geochemical tracers provide complementary information to improve the current understanding of the circulation in the SPNA. To this end, we present the first simultaneous distribution of artificial 129I and 236U in 14 depth profiles and in surface waters along the GEOVIDE section covering a zonal transect through the SPNA in spring 2014. Our results show that the two tracers …