Life Sciences Commons^™

Burrowing And Walking Mechanisms Of North American Moles, Yi-Fen Lin

Doctoral Dissertations

Moles (Family Talpidae) are a classic example of extreme specialization, in their case highly derived forelimb morphologies associated with burrowing. Despite many observations of mole burrows and behaviors gathered in the field, we know very little about how and how well moles use their forelimbs to dig tunnels and to walk within the built tunnels to collect and transport food. The first chapter investigates the effect of soil compactness on two sympatric mole species under controlled laboratory conditions. My results demonstrate that increasing soil compactness impedes tunneling performance as evidenced by reduced burrowing speed, increased soil transport, shorter tunnels, shorter …

Cdna Sequences Of The Caprine Gamma Delta T Cell Hybrid Co-Receptor And Pathogen Recognition Receptor Wc1 Multigene Family, Maria Solangi

Masters Theses

Workshop cluster 1 (WC1) molecules are exclusively expressed on the surface of gamma delta T cells and act as co-receptors and bind pathogens thus also functioning as pattern recognition receptors. The aim was to obtain cDNA evidence to support the recent caprine genome annotation of the WC1 multigene family conducted by a colleague. To get cDNA sequences three strategies were used. Strategy 'I' was used to obtain three clones that corresponded to WC1 SRCR domain d9 through the intracytoplasmic tail sequence. Strategy 'II' was used to obtain 6 clones. A PCR was conducted using SRCR domain b7 through the intracytoplasmic …

Distribution And Population Dynamics Of Ungulates In The Mongolian Gobi, Buuveibaatar Bayarbaatar

Doctoral Dissertations

The Mongolian Gobi is one of the most spectacular and important regions in Central Asia, comprising the largest area of intact grassland in the world. In recent years, a growing human population, expanding exploitation of natural resources, and the development of infrastructure in the region place increasing pressure on these species and their habitats. This dissertation has focused on three species of ungulates such as Mongolian saiga (Saiga tatarica mongolica) in western Mongolia, and Asiatic wild ass (Equus hemionus), and goitered gazelle (Gazella subgutturosa) in Southern Gobi. The study on endangered saiga antelope in …

Regional Recruitment Dynamics And Seasonal Ecology Of Juvenile Bluefish (Pomatomus Saltatrix), David G. Stormer

Doctoral Dissertations

Recruitment in fishes, defined as the survival of a cohort through the first year of life, can be highly variable and affected by small changes in biological and physical factors. Much of the historical focus into the sources of recruitment variability has concentrated on the larval stage, but recent attention has shifted to the relatively longer juvenile period. Spawning behavior that results in the production of multiple cohorts over time and space within a year-class may dampen recruitment variability by decreasing natural mortality risk. The bluefish (Pomatomus saltatrix) is a migratory marine species that produces multiple cohorts of …

Ecological Consequences Of Lost Anadromous Forage Fish In Freshwater Ecosystems, Steven R. Mattocks

Masters Theses

Beginning in the early 1600s, dam construction in New England obstructed anadromous fish access to spawning grounds during migration. As a result, anadromous forage fish populations have declined, which has impacted freshwater, marine, and terrestrial ecosystems. To determine the impacts of dams on anadromous forage fish and freshwater ecosystems, I used historical and current data to estimate population changes in alewives (Alosa pseudoharengus) from 1600-1900. A significant reduction in spawning habitat occurred in New England as a result of 1,642 dams constructed between 1600 and 1900, resulting in 14.8% and 16.6% lake and stream habitat remaining by 1900, …

River Herring Conservation In Freshwater: Investigating Fish Reproductive Success And The Educational Value Of Citizen Monitoring Programs, Meghna Marjadi

Masters Theses

Over the last century anadromous alewife (Alosa psuedoharengus) and blueback herring (Alosa aestivalis), collectively called river herring, suffered drastic declines throughout their range from Newfoundland (Canada) to North Carolina (USA). A 2011 petition to include river herring in the Endangered Species Act (ESA) was rejected, partly due to inadequate information towards identifying coast-wide population status. Additionally, knowledge gaps were identified with basic ecology of the river herring life cycle in freshwater, including species reproductive strategies. In Chapter 2, I investigated how body size, spawning arrival time, and sex influence river herring reproductive success. I collaborated with …

Investigating The Balance Between Estrogen Receptor Mediated Cell Proliferation And Genomic Surveillance, Margarita Brown

Masters Theses

Breast cancer is a leading cause of cancer in women and the second leading cause of cancer death. Lifetime exposure to estrogen contributes to this risk but high dose estrogen has been used to induce apoptosis as treatment for breast cancer. These opposing tumorigenic and anti-tumorigenic effects of estrogen may be regulated differently by the two Estrogen Receptors (ER), Estrogen Receptor alpha (ERα) and Estrogen Receptor beta (ERβ). Although the receptors share a 96% homology in their DNA binding domain, they are unique in the ligand-binding domain with 53% amino acid homology. Previous studies have shown that ERα drives cell …

Factors Affecting Habitat Quality For Wintering Wood Thrushes In A Coffee Growing Region In Honduras, Brett A. Bailey

Masters Theses

Amongst the diversity of taxa that occur in the Neotropics, 200 migratory bird species that breed in temperate North America can be found. Many of these populations have seen significant declines since the 1960s. The Wood Thrush, Hylocichla mustelina, is one such species. Shade coffee and other agroforestry practices show potential for benefiting migratory species, but the quality of coffee habitat and optimal habitat characteristics for Wood Thrushes remain unknown.

I surveyed a spatially complex, agricultural landscape in Honduras outside the recognized winter range of the Wood Thrush and radio-tagged 46 individuals within rustic coffee farms during the winters …

Primate Aesthetics, Chelsea L. Sams

Masters Theses

A cultural, historical, and scientific survey of the phenomena of primate pictorial behavior, presented in a series of interconnected vignettes. What do primates find visually appealing? What is their motivation when creating images? What are the implications for art and for science? By drawing explicit and implicit connections between science, art, case studies, research, and personal narrative, I attempt to weave together what we know, and what we may never be able to know about this complex field.

Population Genetic Analysis Of Atlantic Horseshoe Crabs (Limulus Polyphemus) In Coastal Massachusetts., Katherine T. Johnson

Masters Theses

Atlantic horseshoe crabs (Limulus polyphemus) have endured decades of intense harvest pressure. Genetics studies have shown evidence of distinct sub-groups spanning the coast, although few fine-scale studies have been done to delineate these groups on a local level. Massachusetts lies directly between two of these sub-groups. With documented differences in prosomal widths of horseshoe crabs from either side of Cape Cod, it is possible that Cape Cod is a barrier to gene flow and that there are two distinct genetic groups within Massachusetts. Regulations currently consider all horseshoe crabs to be of one stock. I examined 6 microsatellite …

The Human Intruder Test: An Anxiety Assessment In Rhesus Macaques (Macaca Mulatta), Emily J. Peterson

Masters Theses

The human intruder test (HIT) is a noninvasive tool widely used for assessing anxiety in rhesus macaques (Macaca mulatta). This thesis explores the HIT procedure and applies it to a population of monkeys with a self-injurious behavioral pathology. Individual variation on this test can be used to assess anxiety and temperament. The first experiment of this thesis applied two different procedures of the HIT to 17 monkeys at UMass. Monkeys displayed little response to the intruder, and no significant differences were detected for the two procedures. To determine whether these responses were unique to the UMass monkeys, their …

Associations Between Anxiety And Attention In Laboratory-Housed Rhesus Macaques (Macaca Mulatta), Lauren E. Hobbs

Masters Theses

Previous studies completed with humans have revealed insight into the effects of anxiety on attention tasks such the dot-probe task, but there is little information about such effects on non-human primates. This study aimed to assess whether anxiety or anxious behaviors would impact rhesus macaque performance on a three stimuli paradigm similar to the dot-probe task. Utilizing images of conspecifics (strong threat, mild threat, and neutral), eight monkeys were video recorded completing a task that required them to slide two doors, which held these images, to the side to obtain a treat. We hypothesized that behavioral phenotype (high or low …

Trends In Human-Wildlife Interactions As Related To Land Use And Human Density In Massachusetts, Michael A. Huguenin Jr

Masters Theses

We conducted a study of human-wildlife interactions in Massachusetts, USA between April 2010 and May 2012. Our objectives were to (1) compile and summarize public-generated reports on human-wildlife interactions across Massachusetts; (2) evaluate reports based on species, public concerns, and seasonal distribution; and (3) evaluate public perceptions of human-wildlife interactions. We collected unsolicited reports of human-wildlife interaction submitted to the Massachusetts Division of Fisheries and Wildlife (MDFW) through phone calls, emails, and face-to-face communications from the public. We received 2,730 reports from 332 of 351 towns in Massachusetts regarding 76 different wildlife species ranging from moose (Alces alces) …

A Novel Population Of Natural Killer Cells Plays A Critical Role In The Depletion Of Splenic B2 B Cells During Experimental African Trypanosomiasis, Deborah Frenkel

Doctoral Dissertations

Loss of humoral immune competence in T. brucei-infected mice is associated with the apoptotic depletion of splenic transitional, marginal zone and follicular B cells as well as a depletion of CD8⁺ T cells. This occurs rapidly after infection and impairs responses to vaccine antigens in addition to responses to newly arising VSG antigenic variants, leading to uncontrolled parasite growth and death of the infected mice. Infection-induced B2 B cell and CD8⁺ T cell loss requires the presence of a novel population of natural killer (NK) cells and is mediated by a perforin-dependent process consistent with perforin- and …

The Effects Of Suburbanization On Nest Ectoparasites And Nest Defense Behavior In The Wood Thrush, Evan N. Dalton

Masters Theses

The Wood Thrush (Hylocichla mustelina) is declining throughout its range, yet is capable of persisting in both contiguous forests and small forest patches surrounded by human suburban development. Thus, it is an ideal species for gaining insight into the effects of suburbanization on migrant songbirds. I investigated two aspects of Wood Thrush nesting ecology: nest ectoparasites and nest defense behavior in order to determine if suburbanization influences either aspect. Nests from suburban forests had fewer haematophagous mites, though the abundance of haematophagous blowfly larvae did not differ between suburban and contiguous forests. There was no relationship between the …

Vocal Performance In Songbirds: Territorial Defense And The Development Of Male Song And Female Mating Preferences, Dana L. Moseley

Doctoral Dissertations

The evolution of sexually selected signals has been a major topic of scientific research since Darwin. In recent years, scientists have focused on how elaborate signals can indicate honest information about the quality of their bearers, as predicted by reliability theory. A key concept relating to how mating displays could reliably reveal quality is "performance." Animals face limits in display production, and producing high-­‐performance displays depends on the adept coordination of multiple motor systems. Thus, by observing motor performance, signal-­‐receivers can assess the quality of signalers. Birdsong is a prime example of a display that involves motor challenges in its …

Cd4 Silencing In Thymocytes Is Opposed By The Enforced Association Of P300 Hat, Hdac1 Or Suv39h1 With Runx Transcription Factors, Christyne Ayne Kane

Doctoral Dissertations

The transcription factors Runx1 and Runx3 are required for permanent silencing of CD4 in maturing CD8+ thymocytes. Runx binding to consensus sites within the CD4 silencer region is required for CD4 silencing post-positive selection. The Runx nuclear matrix targeting sequence (NMTS) is required for CD4 silencing and is implicated in binding to the histone acetyltransferase (HAT) p300, histone deacetylases (HDAC), and histone methyltransferase (HMT) SUV39H1 proteins. Epigenetic modifications of chromatin or post-translational modifications of Runx itself as a result of Runx association with these enzymes may be important for establishment of long-term CD4 silencing. In this study, we show that …

Birdsong Variation As A Source Of Information For Migrating Common Yellowthroats, Rachel Theresa Bolus

Open Access Dissertations

Social information affects the movement decisions of animals and is often an essential factor in habitat selection. Social information should be especially relevant to long-distance migrating birds that navigate over long distances through unfamiliar habitats to find resources to survive. This information likely varies in both availability and importance at the different spatial scales relevant to migrating birds. Using the common yellowthroat as a case study, I tested whether cues might be available in the songs of locally breeding birds at the continental, within-site, and within-territory scales. At the continental scale, I described the geographic variation in song among genetic …

Performance And Signaling In The Green Anole Lizard, Justin P. Henningsen

Open Access Dissertations

Green anoles are small lizards of the Southeastern United States. They possess an extensible throat-fan called a dewlap. Males have larger dewlaps and display them more often than females. Displays occur during courtship, during agonistic interaction, and during encounters with potential predators. The size of the dewlap of male green anoles is positively correlated with maximum bite force capacity. Bite force capacity, in turn, is predictive of the winner during agonistic interactions. The correlation between these traits suggests that dewlap size may be used as a reliable signal of maximum bite force capacity. In this dissertation, I address three components …

Molecular Characterization Of The Pathophysiology Of The Digital Laminae In Acute Carbohydrate-Induced Equine Laminitis, Erica Ann Pawlak

Open Access Dissertations

Equine laminitis is a devastating condition that results in the failure of the tissue responsible for suspending the skeleton within the hoof capsule. The digital laminae is composed of two interdigitated layers, the dermal lamellae surrounding the distal pedal bone, and the epidermal lamellae, which interfaces with the hoof wall. During laminitis, these layers separate, allowing for rotation and sinking of the pedal bone. While there are multiple diseases and physiological conditions associated with the development of laminitis, including sepsis, metabolic syndrome, and unequal weight bearing, the exact cause remains elusive. Prior work by our research group identified the metalloprotease …

The Role Of Notch In Th17 Differentiation, Reem Suleiman

Open Access Dissertations

Th17 cells are pro-inflammatory cells that are characterized by the production of their signature cytokine, IL-17. Although they are thought to have arisen to protect against extracellular bacteria and fungi they have been shown to mediate autoimmune diseases such as EAE and psoarisis. Notch protein is a cell-surface receptor that has been widely conserved among species. It plays an essential role in determining multiple cell fates. More recently, it has been implicated in regulating peripheral CD4+ T-cell responses. In these studies, we report that blockade of Notch signaling significantly down-regulates the production of IL-17 and associated cytokines in both mouse …

Ecology And Conservation Of The Montane Forest Avian Community In Northeastern North America, William V. Deluca

Open Access Dissertations

Montane forests provide habitat for unique assemblages of flora and fauna that contribute significantly to a region’s biodiversity. Previous work indicates that montane forest ecosystems are exceedingly vulnerable to a host of anthropogenic stressors including climate change, atmospheric deposition, and recreation, to name a few. Montane forests and other high elevation ecosystems are considered to be among the first and most severely impacted by climate change. It is therefore, imperative to evaluate anthropogenic impacts on montane ecosystems and maintain reliable monitoring methods that are capable of tracking potential shifts in the distribution of species dependent on these systems. I surveyed …

Distributions Of Large Mammal Assemblages In Thailand With A Focus On Dhole (Cuon Alpinus) Conservation, Kate Elizabeth Jenks

Open Access Dissertations

Biodiversity monitoring and predictions of species occurrence are essential to develop outcome-oriented conservation management plans for endangered species and assess their success over time. To assess distribution and patterns of habitat use of large mammal assemblages in Thailand, with a focus on the endangered dhole (Cuon alpinus), I first implemented a long-term camera-trapping project carried out with park rangers from October 2003 through October 2007 in Khao Yai National Park. This project was extremely successful and may serve as a regional model for wildlife conservation. I found significantly lower relative abundance indices for carnivore species, and collectively for all mammals …

The Roles Of Notch1 And Pkc-Θ In Immune Mediated Bone Marrow Failure, Justine E. Roderick

Open Access Dissertations

We sought to evaluate the individual contributions of Notch1 and PKC-ζ to disease progression in a mouse model of immune-mediated bone marrow failure and to define a mechanism for their potential cellular cooperation. We transferred parental bulk splenocytes into F1-hybrid recipients to induce a robust immune-mediated bone marrow failure (BMF) that we could partially rescue by administering a pharmacological inhibitor of Notch activation. Transferring splenocytes from PKC--ζ-/- animals did not induce disease, and treating animals with a pharmacological inhibitor of PKC-ζ also provided full protection from disease. We found that inhibiting Notch1 resulted in PKC-ζ down-regulation, and blocking PKC-ζ reduced …

Avian Ecology And Conservation In Tropical Agricultural Landscapes With Emphasis On Vermivora Chrysoptera, Richard Brooks Chandler

Open Access Dissertations

The world's biodiversity is concentrated in tropical ecosystems, yet tropical forests are being converted for agriculture at a rapid rate. I evaluated the potential of an alternative coffee production system known as Integrated Open Canopy (IOC) to contribute to avian conservation. This study was conducted from 2005-2010 in the Cordillera de Tilarán, Costa Rica. My results indicate that species richness of forest-dependent birds was higher in IOC farms than in shade coffee farms, and was comparable to secondary forest sites. There was no difference in species richness of Neotropical-Nearctic migrants between IOC and shade coffee farms. Overall similarity was higher …

Innate Immune Responses To B. Burgdorferi Mediated By Jnk1 And The Cochaperone, Methylation Controlled Dnaj (Mcj), Hooman Izadi

Open Access Dissertations

The infections agent of Lyme disease, Borrelia Burgdorferi is a complex microorganism with a highly diverse genome. One of the most remarkable aspects of the B. burgdorferi genome is the large number of sequences encoding predicted or known lipoproteins, including outer-surface proteins. The B. burgdorferi genome encodes no recognizable toxins. Instead, this extracellular pathogen causes pathology by migration through tissues, adhesion to host cells, and evasion of immune clearance. Inflammation elicited by infection with B. burgdorferi depends on the ability of the spirochete to survive in the mammalian host, as well as the immune response that arises upon the interaction …

Growth Of Atlantic Salmon (Salmo Salar) In Freshwater, Douglas Bradlee Sigourney

Open Access Dissertations

Growth plays a key role in regulating ecological and population dynamics. Life history characteristics such as age at maturity, fecundity and age and size at migration are tightly linked to growth rate. In addition, size can often determine survival and individual breeding success. To fully understand the process of growth it is important to understand the mechanisms that drive growth rates. In Atlantic salmon, growth is critical in determining life history pathways. Models to estimate growth could be useful in the broader context of predicting population dynamics. In this dissertation I investigate the growth process in juvenile Atlantic salmon (Salmo …

Identifying Critical Fish Habitat And Long-Term Trends In Fish Abundances In The Hudson River Estuary, Megan Patricia O'Connor

Open Access Dissertations

The Hudson River estuary (HRE) is a well monitored aquatic resource and much secondary data exist for this system. We developed two objectives based on accessible HRE aquatic data. The first objective was to determine if changes in HRE fish community over the time period (1974 to 2005) years are correlated to local and regional climate. We addressed this objective by employing a multivariate statistical approach. We confirmed that the HRE fish community structure has changed over the time period (1974 to 2005). These changes are correlated with local hydrology (freshwater flow and water temperature) and regional climate (Atlantic Multidecadal …

Evaluation Of Disturbance Factors And Their Effect On Breeding Common Loons At Lake Umbagog National Wildlife Refuge, New Hampshire And Maine, Kyle P. Mccarthy

Open Access Dissertations

Virtually any person exposed to American movies or television has likely heard the call of a common loon (Gavia immer). Its use as a sound prop has become ubiquitous in any scene related to the outdoors or the wilderness, even if the area filmed is in no way related to true loon habitat. The reason behind this is that the common loon and its haunting cries have come to symbolize the great outdoors. The sound of their call is meant to make the audience feel like the scene they are watching is in a remote area, far from the trappings …

Seasonal Home Range Sizes, Transboundary Movements And Conservation Of Elephants In Northern Tanzania, Alfred P. Kikoti

Open Access Dissertations

Although the unprotected lands of northern Tanzania support large numbers of elephants, and provide critical linkages for wildlife movements across the region, there is little information on the dispersal patterns of elephants in these unprotected lands. Our home range measures (100% MCP) of 21 elephants with satellite collars in four study regions were highly variable (191 to 3,698 km2). Home range sizes (95% fixed kernel) of bulls were typically larger than those of females, and wet season ranges were typically larger than dry season ranges. There were large differences in average home range sizes reflected varying strategies for obtaining food …