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Ecological Determinants Of Survival And Reproduction In The Spotted Hyena, Heather E. Watts

Biology Faculty Works

Large carnivores play a key role in the structuring and dynamics of many ecosystems, yet the factors influencing dynamics of carnivore populations themselves are often poorly understood. Spotted hyenas (Crocuta crocuta) are the most abundant large carnivores in many African ecosystems. We describe demographic patterns in a population of spotted hyenas observed continuously for 15.5 years, and assess the effects of per capita prey availability, interspecific competition, rainfall, anthropogenic disturbance, and disease on 2 key determinants of population dynamics: reproduction and survival. Annual reproduction, survival of juveniles (i.e., recruitment to adulthood), and mortality of adults varied among years of the …

Risk-Sensitive Foraging Facilitates Species-Level Trophic Cascades Among Terrestrial Mammals: A Meta-Analysis, Bryan David Murray

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The widespread removal of large carnivores from terrestrial ecosystems may be contributing to plant species loss and biotic homogenization through trophic cascades. A few plants not preferred by ungulates are increasing in abundance while the majority of preferred plants are in decline. A meta-analysis of recruitment gaps in browse-sensitive tree species demonstrated that failed recruitment coincided in time with carnivore loss. In all studies recruitment continued in nearby browsing refugia. A second meta-analysis revealed that the mechanism of mammalian herbivore-mediated trophic cascades contains a behavioral component. Foraging mammals exhibited higher giving-up densities (GUDs) when under higher predation risk. GUDs were …

A Potential Strategy To Maintain Hsv-1 In A Latent State: Use Of Immunoregulatory Peptide Mimetics, Nasrin Majidi

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This study reviews the role of interferon-gamma (IFN-gamma) in HSV-1 latency. CD8+ T cells inhibit the reactivation of HSV-1 in trigeminal ganglia (TG) by production of IFN-gamma. Although CD8+ T cells include all the cytotoxic apparatus for cytotoxicity, latently infected neuronal cells are not killed by CD8+ T cells. The CD94-NKG2a molecule on CD8+ T cells, binds to Qa-1b (a MHC class I like molecule) present on neuronal cell to inhibit CD8+ T cells cytotoxicity. Other studies have also determined that the IFN-gamma peptide mimetic 95-132 inhibits HSV-1 replication in the same way as IFN-gamma in infected cells. IFN-gamma mimetic …

Finding The Trophic Trickle: Using Herbaceous Indicator Species To Investigate Plant Recovery From Intense Browsing By White-Tailed Deer (Odocoileus Virginianus) After The Re-Colonization Of A Top Predator (Canis Lupus), Krystle A. Bouchard

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High densities of white-tailed deer (Odocoileus virginianus) have been implicated in changing forest community structure and composition. Top predators, including gray wolf (Canis lupus), were extirpated from much of their range by the mid 1900s, but have since returned to Northern Wisconsin. To determine whether the re-colonization of wolves could initiate a trophic cascade resulting in the recovery of understory plants from deer browsing, I surveyed four herbaceous species in areas without wolves and areas with 4-6 year old wolf packs and 12-13 year old wolf packs. Plant size and reproduction were greater in areas where wolves had been for …

Immunolocalization And Changes In Expression Levels Of Glyceroporin Hc-3 In Several Tissues Of Gray Tree Frogs, Hyla Chrysoscelis Under Different Physiological Conditions, Sushmita Yaganti

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Previous studies show that aquaporin HC-3 in gray tree frogs, Hyla chrysoscelis, a homolog of mammalian AQP3 is an aqua glyceroporin also responsible for freeze tolerance. Our study tried to localize and compare the protein expression levels of aquaporin HC-3 in seven different organs of gray tree frogs under five different physiological conditions using immuno histofluorescence and western blot. HC-3 was immunolocalized in the epidermis and dermis of the skin, basolateral portion of the collecting ducts in the kidney, red blood cells in the liver and other tissues, muscle Schwann cells and the basolateral portion of the large intestine epithelial …

Inflammatory Cytokines In Jet Propulsion Fuel-8 Induced Irritant Contact Dermatitis In Male Fischer Rats, Thomas Joseph Kannanayakal

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Contact dermatitis is one of the most common occupational diseases. Absenteeism of the affected workers and associated health care costs makes this disease an economically important issue. Irritant contact dermatitis (ICD) is a common contact dermatitis observed among workers. As each category of irritants triggers the inflammatory process by different method, studying the mechanism of ICD is difficult. Information on the mechanism of action of an irritant is indispensable for the development of effective prophylactic and therapeutic measures. In this study, we have investigated the early changes in rat skin induced by jet fuel-8 (JP-8). Although previous studies have described …

Physiological Effects On The Expression Of Aquaporin 1-Like Hc-1 In Cope's Gray Tree Frog, Hyla Chrysoscelis, Ram Naresh Pandey

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Aquaporin 1 is a cell membrane integral protein, which functions for water transport through the hydrophobic cell membrane to the cytoplasm. HC-1 is an aquaporin 1-like protein expressed in Hyla chrysoscelis and amphibian that survives at sub-freezing temperatures in its natural habitat. The goal of the current study was to investigate the expression of HC-1 during changing physiological conditions. The expression level of HC-1 was determined in skin, muscle, liver, kidney, and intestines of warm, cold, frozen, and dehydrated frogs using Western blot and immunohistofluorescence. Although HC-1 was widely distributed, the expression level varied among tissues and physiological conditions. In …

The Influence Of Temperature On Population Growth And Allergen Production In Cultured House Dust Mites - Dermatophagoides Pteronyssinus And Dermatophagoides Farinae, Lakshmi Yella

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Dermatophagoides pteronyssinus and Dermatophagoides farinae are commercially cultured to produce materials to make extracts for diagnostic tests and immunotherapy. There is some speculation as to how the culture conditions such as time of culture, temperature, relative humidity and food might influence the mite populations and subsequent production of allergens. The purpose of our investigation was to see how temperature influenced the population growth and allergen production of cultured house dust mites. D. pteronyssinus and D. farinae were cultured at 20°C and 25°C. Samples were collected at two week intervals for live mite count, life stage composition and to determine Group …

A Redescription Of Three Species Of Monoecocestus (Cestoda: Anoplocephalidae) Including Monoecocestus Threlkeldi Based On New Material, Terry R. Haverkost, Scott Lyell Gardner

Scott L. Gardner Publications

Because we have new and detailed data on species in the genus, herein we redescribe both Monoecocestus macrobursatus and M. minor based on existing museum specimens. We also redescribe M. threlkeldi (Parra, 1952) using material collected in Bolivia. Based on the specimens representing M. thelkeldi, we affirm that Perutaenia Parra, 1953 should remain a junior synonym of Monoecocestus.

Sex Effects On Life Span And Senescence In The Wild When Dates Of Birth And Death Are Unknown, Felix Zajitschek, Chad Brassil, Russell Bonduriansky, Robert C. Brooks

School of Biological Sciences: Faculty Publications

Males and females allocate and schedule reproductive effort in very different ways. Because the timing and amount of reproductive effort influence survival and thus the optimization of life histories, mortality and senescence are predicted to be sex specific. However, age-specific mortality rates of wild animals are often difficult to quantify in natural populations. Studies that report mortality rates from natural populations are, therefore, almost entirely confined to long-lived, easy-to-track species such as large mammals and birds. Here, we employ a novel approach using capture–mark–recapture data from a wild population of black field crickets (Teleogryllus commodus) to test for …

Blood Sampling Reduces Annual Survival In Cliff Swallows (Petrochelidon Pyrrhonota) -- La Toma De Muestras De Sangre Reduce La Supervivencia Anual En Petrochelidon Pyrrhonota, Charles R. Brown, Mary Bomberger Brown

School of Biological Sciences: Faculty Publications

Researchers commonly collect blood samples from wild birds, and most workers assume that blood sampling has no adverse effect on the birds’ survival. Few studies, however, have done controlled comparisons among bled and non-bled individuals and estimated survival using modern statistical methodology. We used a data set on Cliff Swallows (Petrochelidon pyrrhonota) that included 2,945 bled and 7,822 non-bled birds captured at the same times and sites in southwestern Nebraska from 1986 to 2006 to estimate annual survival and recapture probabilities of each group. Blood was collected with brachial venipuncture in amounts varying from 0.3% to 1.2% of …

Evolution And Pleiotropy Of Trithorax Function In Arabidopsis, Zoya Avramova

School of Biological Sciences: Faculty Publications

The SET domain-containing genes of the TRITHORAX family encode epigenetic factors that maintain the expression of targeted genes. Trithorax homologs have been found in both animals and plants. Since these are thought to have evolved multicellularity independently, common mechanisms of epigenetic regulation must be evolutionarily ancient and derived from a common ancestor. In addition, each lineage has evolved unique mechanisms to expand the original repertoire of epigenetic functions. Phylogenetic analysis of SET domain proteins has outlined some intriguing evolutionary trends. In plants, epigenetic gene silencing mechanisms have been aggressively pursued. In contrast, studies of epigenetic mechanisms maintaining active gene expression …

Caenorhabditis Elegans Genomic Response To Soil Bacteria Predicts Environment-Specific Genetic Effects On Life History Traits, Joseph D. Coolon, Kenneth L. Jones, Timothy C. Todd, Bryanua C. Carr, Michael A. Herman

School of Biological Sciences: Faculty Publications

With the post-genomic era came a dramatic increase in high-throughput technologies, of which transcriptional profiling by microarrays was one of the most popular. One application of this technology is to identify genes that are differentially expressed in response to different environmental conditions. These experiments are constructed under the assumption that the differentially expressed genes are functionally important in the environment where they are induced. However, whether differential expression is predictive of functional importance has yet to be tested. Here we have addressed this expectation by employing Caenorhabditis elegans as a model for the interaction of native soil nematode taxa and …

The Nuclear Receptor Nhr-25 Cooperates With The Wnt/Β-Catenin Asymmetry Pathway To Control Differentiation Of The T Seam Cell In C. Elegans, Martina Hajduskova, Marek Jindra, Michael A. Herman, Masako Asahina

School of Biological Sciences: Faculty Publications

Asymmetric cell divisions produce new cell types during animal development. Studies in Caenorhabditis elegans have identified major signal-transduction pathways that determine the polarity of cell divisions. How these relatively few conserved pathways interact and what modulates them to ensure the diversity of multiple tissue types is an open question. The Wnt/β-catenin asymmetry pathway governs polarity of the epidermal T seam cell in the C. elegans tail. Here, we show that the asymmetry of T-seam-cell division and morphogenesis of the male sensory rays require NHR-25, an evolutionarily conserved nuclear receptor. NHR-25 ensures the neural fate of the T-seam-cell descendants in cooperation …

Ecological Genomics Of Nematode Community Interactions: Model And Non-Model Approaches, Michael A. Herman, Joseph D. Coolon, Kenneth L. Jones, Timothy Todd

School of Biological Sciences: Faculty Publications

The effects of human-induced environmental change are evident at multiple levels of biological organization. To date, most environmental change studies have focused on effects at the ecosystem, community, and organismal levels. However, the ultimate controls of biological responses are located in the genome. Thus, genetic and genomic studies of organismal responses to environmental changes are necessary. Recent advances in genome analysis now make such analyses possible. In this chapter we describe a research approach and program that can begin to span this gap by using genome-enabled approaches to characterize organismal changes and then employing a genetically tractable model organism to …

A Study Of The Waterborne And Dietary Toxicityof Cadmium To Hydra Attenuata And Daphnia Plux In Soft Waters And The Development Of Biotic Ligand Models To Predict Such Toxicity, Matthew S.A. Clifford

Theses and Dissertations (Comprehensive)

The goal of this thesis was to compare the effects of waterborne Cd exposures and dietary Cd exposures to Hydra attenuata. Before the Hydra could be exposed to dietborne exposures of Cd, the effects of waterborne exposures had to be understood. This was done by looking at the sensitivity of D. pulex to Cd and then understanding the accumulation of Cd. After bioaccumulation patterns of Cd. to D. pulex were known, we could then feed the prey to the Hydra and comapre the effects to waterborne effects of Cd to Hydra.

To understand the waterborne effects of Cd to …

Using Chemical, Optical And Biological Methods To Characterize Cu Complexation By Different Natural Organic Matter Sources Collected From Canadian Shield Waters, Keegan Andrew Hicks

Theses and Dissertations (Comprehensive)

The effects of natural organic matter (NOM) source on Cu complexation were characterized chemically, optically and biologically in soft waters. NOM from different Canadian Shield soft water lakes were concentrated using reverse osmosis and for comparison NOM was also sampled from a hard water source. NOM complexation capacity was assessed directly in Cu spiked solutions (with and without additions of NOM) by measuring free Cu activity using an ion selective electrode. Additional chemical and optical characterizations of NOM included specific absorbance coefficient (SAC; at 340 nm), excitation-emission matrix spectroscopy, protein content, and molecular weight fractionation (fraction of DOCkDa). The biological …

Green Heating And The Mckillop Library Building, Alexandra Riewer, Anthony Rothwell, Kalei Sullivan, Other Student

BIO140 Carbon Footprint Project

As global warming becomes an ever increasing problem, it is Salve Regina University and the Newport communities job to do their part. In an effort to reduce their carbon footprint, we performed a series of tests on the heating and building of McKillop library at Salve Regina to measure its carbon emissions and environmental impact. As a team, we tested for areas of heat loss and temperature change and internal temperature and humidity fluctuation. We also focused on the types of insulation that the building uses and the efficiency of its HVAC – heating, ventilation, and air conditioning – system. …

Dynamics Of Aggregation Formation In Japanese Beetles, Popillia Japonica, Katelyn A. Kowles

Masters Theses

For most insect aggregations to form, they need to be started by an initial individual (the pioneer) andjoined by later individuals (the joiners). Pioneers and joiners may differ with regard to characteristics such as sex and body size. We carried out three field experiments to examine the characteristics of Japanese beetles, Popillia japonica, pioneering and joining aggregations on host plants. Individual beetles were captured as they arrived on uninhabited grape plants, as well as plants designed to simulate aggregations with model beetles and feeding damage. For all experiments and treatments, the beetles arriving were significantly female-biased, with pioneer females having …

Ecology And Impacts Of Lianas In Regenerating Forests, Laura Marie Ladwig

Masters Theses

Although they are important components of forest communities, the general ecology of temperate lianas, especially during forest regeneration, is largely unknown. The dependence of lianas on other plants for physical support makes them a potentially important driver of community dynamics. I examined current and past vegetation data from an old-field succession study in the Piedmont region of New Jersey, USA to determine the dynamics of liana expansion and their role in forest regeneration. Fifty years of vegetation data were utilized to determine community controls and population dynamics oflianas during expansion. Five lianas, Celastrus orbiculatus, Lonicera japonica, Parthenocissus quinquefolia, Toxicodendron radicans, …

Aging In The Mammalian Olfactory System, Stephen Clark

Masters Theses

The purpose of this investigation was to investigate genetic and age~related differences in the mammalian olfactory system. The molecule of interest is apolipoprotein E (apoE), a component oflipoprotein molecules which functions in the transport of cell membrane components (triglycerides, lipids, and cholesterol). Specifically in the nervous system, apoE is synthesized by glial cells that function in recycling dead nervous tissue components for delivery to growing or dividing neurons. ApoE is present in three protein isofon11s: apoE2, which has been associated with type III hyperlipoproteinemia; apoE3, rhe normal human isoforrn; and apoE4, which has been associated with Alzheimer's disease (AD). The …

Interaction Of Apoe With Estrogen In The Olfactory System During Nerve Maintenance And Recovery, Michael M. Tonsor Ii

Masters Theses

Estrogen replacement profoundly aids in nerve regeneration after injury in adult mammalian models. Estrogen replacement also protects against olfactory dysfunction in mammals. The mechanism underly1ng estrogen's neuroprotective effects remains ambiguous. My goal is to investigate and better clarify if apolipoprotein E (apoE ), a lipid transporting protein, is a critical intermediary to estrogen's effects on nerve maintenance and regeneration.

My hypothesis is that apoE is a mediator of estrogen's beneficial effects. This hypothesis is based on the following observations from previous studies. First, olfactory nerve regeneration was delayed in apoE-gene knockout (KO) mice as compared to wild type (WT) mice. …

Fragmentation Effects On Fitness In Five Common Prairie Species, Lydia Miramontes Loyd

Masters Theses

Midwest tallgrass prairies have suffered extensive habitat loss and as a result persist as isolated and highly fragmented remnants. In such small, isolated remnants, genetic drift and inbreeding depression can lead to a loss of genetic variation over time. Reduced genetic variation is often associated with reduced levels of growth, survival, and reproduction as well as increased susceptibility to stress. This study examined fitness traits of five common prairie species to determine whether plants in small fragmented remnants had reduced fitness as compared to those in a larger remnant. Five prairie species were chosen for this study based on their …

Nest Success, Nesting Habitat, & Nestling Feeding Rates Of Red-Headed Woodpeckers In East-Central Illinois, Nathan Cole Hudson

Masters Theses

The Red-headed Woodpecker (Melanerpes erythrocephalus) is a classic oak savanna species that has suffered significant population declines caused, in part, by extensive loss of savanna habitat and agricultural development. Despite consistent data that reveal a dramatic decline throughout much of their range, few studies have examined other possible explanations. In an effort to determine potential causes for their continued decline (as well as add to existing knowledge of nesting biology), we examined nest success and nesting micro-habitat features. We compared micro-habitat variables at: 1) golf and non-golf course sites, 2) successful and failed nest sites, and 3) nest and random …

Long-Term Assessment Of Predatory Fish Removal On A Pond-Breeding Amphibian Community In Central Illinois, Lee M. Gross

Masters Theses

Habitat loss and fragmentation are important contributors to population declines in many species, so maintaining suitable habitat has become a priority for wildlife management. Removal of introduced fish can help restore suitable habitats for amphibian populations, although long-term assessments of such removals are lacking at the community level. In 2001, drift fences and pitfall traps were constructed around the majority of four ponds to monitor an amphibian community in a nature preserve in central Illinois. Rotenone™ was applied to ponds containing introduced fish in 2001, and again, in 2003. I collected data from 2005-2007 to determine the long-term impacts of …

Habitat Selection And Niche Partitioning Of Fox And (Sciurus Niger) And Gray (Sciurus Carolinensis) Squirrels In Charleston, Il, Katelyn Marti

Masters Theses

Two species of tree squirrels inhabit Charleston, IL; fox squirrels (Sciurus niger) and gray squirrels (Sciurus caro/inensis). Although these species are sympatric throughout much of the eastern U.S., urban settings are usually occupied by one or the other. In the few localities where they co-occur, little is known about how they partition habitat. Therefore, the objectives of my study were to determine: (1) the relative abundance of each species, (2) whether habitat use differs between species, (3) if habitat use shifts with season, time of day, domestic predator abundance, or mast availability, and (3) observe interspecific and intraspecific interactions. The …

Micrornas And Metazoan Macroevolution: Insights Into Canalization, Complexity, And The Cambrian Explosion, Michael Dietrich, Mark Mcpeek, Kevin J. Peterson

Dartmouth Scholarship

One of the most interesting challenges facing paleobiologists is explaining the Cambrian explosion, the dramatic appearance of most metazoan animal phyla in the Early Cambrian, and the subsequent stability of these body plans over the ensuing 530 million years. We propose that because phenotypic variation decreases through geologic time, because microRNAs (miRNAs) increase genic precision, by turning an imprecise number of mRNA transcripts into a more precise number of protein molecules, and because miRNAs are continuously being added to metazoan genomes through geologic time, miRNAs might be instrumental in the canalization of development. Further, miRNAs ultimately allow for natural selection …

Landcover Change And Population Dynamics Of Florida Scrub-Jays And Florida Grasshopper Sparrows, David Breininger

Electronic Theses and Dissertations

I confronted empirical habitat data (1994-2004) and population data (1988-2005) with ecological theory on habitat dynamics, recruitment, survival, and dispersal to develop predictive relationships between landcover variation and population dynamics. I focus on Florida Scrub-Jays, although one chapter presents a model for the potential influence of habitat restoration on viability of the Florida Grasshopper Sparrow. Both species are unique to Florida landscapes that are dominated by shrubs and grasses and maintained by frequent fires. Both species are declining, even in protected areas, despite their protected status. I mapped habitat for both species using grid polygon cells to quantify population potential …

Tissue Engineered Myelination And The Stretch Reflex Arc Sensory Circuit: Defined Medium Formulation, Interface Design And Microfabrication, John Rumsey

Electronic Theses and Dissertations

The overall focus of this research project was to develop an in vitro tissue-engineered system that accurately reproduced the physiology of the sensory elements of the stretch reflex arc as well as engineer the myelination of neurons in the systems. In order to achieve this goal we hypothesized that myelinating culture systems, intrafusal muscle fibers and the sensory circuit of the stretch reflex arc could be bioengineered using serum-free medium formulations, growth substrate interface design and microfabrication technology. The monosynaptic stretch reflex arc is formed by a direct synapse between motoneurons and sensory neurons and is one of the fundamental …

The Evolution Of Photoperiodic Response Systems And Seasonal Gnrh Plasticity In Birds, Heather E. Watts

Biology Faculty Works

Animals’ lives are typically subdivided into distinct stages, some of which (e.g. breeding) contribute to fitness through enhancing current reproductive success, and some of which (e.g. molting and migration in birds; hibernation in mammals) contribute to fitness through enhancing survival and, therefore, future reproductive opportunities. There is often a trade-off between these two kinds of processes, either because they are temporally incompatible with one another (e.g. migration precludes simultaneous nesting in birds) or because they are energetically incompatible with one another (e.g. successful molting appears to be incompatible with simultaneous nesting in many birds). Consequently, adaptations facilitating appropriate timing and …