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A Population Genetic Study Of The Zostera Marina (Eelgrass) Ecotypes Of Barnegat Bay, New Jersey And Implications For Grass Bed Restoration, Stephanie Marie Smith

Theses, Dissertations and Culminating Projects

Zostera marina is a species of seagrass widely found in the northern Atlantic and northern Pacific Oceans. It is primarily a cold-water adapted plant that is capable of both sexual and asexual reproduction. Zostera marina serves many ecological roles, including stabilizing sediments, reducing current velocity, preventing erosion and providing food and shelter to many organisms. Eelgrass populations have suffered numerous large-scale declines due to both natural as well as human-induced causes. Specifically within Bamegat Bay, New Jersey, the Z. marina populations have declined by over 62% within the past 20 years. Restoration efforts have had diverse growth and survival rates, …

Genetic Analysis Of Germline Development In The Model Organism C. Elegans, Kaitlyn A. Wurz

Renée Crown University Honors Thesis Projects - All

My research investigated the relationships among several transcriptional and/or post-transcriptional regulators in the C. elegans germ line. I examined the relationship between the rha-1 gene and three other regulatory genes, ego-1, glp-1 and csr-1. These genes function in germline proliferation and differentiation and are required for fertility. Because these genes regulate similar processes, we have investigated the relationships among them. The rha-1 gene encodes an RNA helicase that is required for germline development, chromatin regulation, and RNA interference (RNAi). The ego-1 gene encodes an RNA-directed RNA polymerase that is also required for these processes. Although many of the rha-1 and …

The Role Of Estrogen Receptor Beta In Neonatal Oocyte Development, Kelsey E. Breen

Renée Crown University Honors Thesis Projects - All

Establishment of the pool of primordial follicles is essential for reproduction. Shortly after their formation, female germ cells undergo a series of incomplete cell divisions resulting in clusters called cysts. After birth, mouse germ cell cysts break down into individual oocytes (a process referred to as cyst breakdown) that are surrounded by somatic pre-granulosa cells to form primordial follicles. During the process of cyst breakdown, a subset of oocytes in each cyst dies with only a third of the initial number of oocytes surviving. The mechanisms controlling cyst breakdown and programmed cell death are unknown. Previous studies have focused on …

Root Production And Herbivory In An Upland Grassland Community In Yellowstone National Park, Anna M. Stewart

Renée Crown University Honors Thesis Projects - All

Few investigations have been conducted on belowground plant consumption and production due to the difficulty of examining root systems over time without significant disturbance. In most field studies, roots are sampled monthly, a time interval that cannot capture the rapid growth and death of fine roots. The purpose of this study was to estimate rates of root production (growth) and consumption in an upland grassland inYellowstoneNational Park. Root lengths were digitized in four minirhizotron tubes, four times per month (at three-day intervals over ten days) from May - September 2005. I attributed root length that disappeared over each three-day period …

Transcription And Rna Interference In The Formation Of Heterochromatin, Shiv Grewal, Sarah C.R. Elgin

Biology Faculty Research

Transcription in heterochromatin seems to be an oxymoron--surely the 'silenced' form of chromatin should not be transcribed. But there have been frequent reports of low-level transcription in heterochromatic regions, and several hundred genes are found in these regions in Drosophila. Most strikingly, recent investigations implicate RNA interference mechanisms in targeting and maintaining heterochromatin, and these mechanisms are inherently dependent on transcription. Silencing of chromatin might involve trans-acting sources of the crucial small RNAs that carry out RNA interference, but in some cases, transcription of the region to be silenced seems to be required--an apparent contradiction.

A Database Of Wing Diversity In The Hawaiian Drosophila, Kevin A. Edwards, Linden T. Doescher, Kenneth Y. Kaneshiro, Daisuke Yamamoto

Faculty Publications – Biological Sciences

Background. Within genus Drosophila, the endemic Hawaiian species offer some of the most dramatic examples of morphological and behavioral evolution. The advent of the Drosophila grimshawi genome sequence permits genes of interest to be readily cloned from any of the hundreds of species of Hawaiian Drosophila, offering a powerful comparative approach to defining molecular mechanisms of species evolution. A key step in this process is to survey the Hawaiian flies for characters whose variation can be associated with specific candidate genes. The wings provide an attractive target for such studies: Wings are essentially two dimensional, and genes controlling wing shape, …

The Tadpole Of Eupsophus Queulensis (Anura, Cycloramphidae), Diana R. Cárdenas-Rojas, Alberto Veloso, Rafael O. De Sá

Biology Faculty Publications

The genus Eupsophus is characterized by endotrophic larvae that inhabit water-filled cavities. The larvae feed from large yolk reserves during metamorphosis. The external morphology has been described for four of the ten known species and data on larval chondrocranial morphology are available only for one. We describe the extema1 morphology, oral disc and chondrocranial anatomy of the larvae of Eupsophus queulensis. The characteristics of E. queulensis tadpoles are compared with those of other Eupsophus larvae.

A Role For Sperm In Regulation Of Egg-Laying In The Nematode C. Elegans, Marie Mcgovern, Ling Yu, Mary Kosinski, David Greenstein, Cathy Savage-Dunn

Publications and Research

Background In insects and in mammals, male sperm and seminal fluid provide signaling factors that influence various aspects of female physiology and behavior to promote reproductive success and to compete with other males. It is less apparent how important such signaling is in the context of a self-fertile hermaphrodite species. We have addressed this question in the nematode Caenorhabditis elegans, which can reproduce either by hermaphrodite self-fertilization or by male-hermaphrodite mating.

Results We have studied the egg-laying defective mutant, egl-32, and found that the cellular basis of the egl-32 egg-laying phenotype is likely a defect in sperm. First, the time …

Identification And Control Of Pest Slugs And Snails For Broadacre Crops In Western Australia, Svetlana Micic, Ken Henry, Paul Horne

Bulletins 4000 -

The numbers of slugs and snails have increased in broadacre cropping in Western Australia with the use of minimum tillage and stubble-retention practices. The organic content of paddocks increases under such systems, providing an increased food source especially to young slugs and snails. Soil moisture content is greater over summer leading to higher survival levels of slugs and snails.

Slug and snail pests in Australia have come from other countries, mainly the Mediterranean region. They damage plant seeds (mainly legumes), recently germinated seeds, seedlings and leaves and can be a contaminant of grain at harvest.

Improving Natural History Research With Image Analysis: The Relationship Between Skin Color, Sex, Size And Stage In Adult Red-Spotted Newts, Andrew K. Davis, Kristine L. Grayson

Biology Faculty Publications

Natural history researchers are increasingly using digital cameras and computer software to measure their study animals. Adult Red-spotted Newts (Notophthalmus viridescens viridescens) are known to display a range of skin colors, from brown to green, but it has not been possible to quantify this variation until the advent of image analysis technology. We used an image analysis approach to compare skin color between sexes, across a range of sizes, and between aquatic and post-breeding (emigrating to the terrestrial habitat) stage adult newts. From 232 individuals (53% male, 47% female) we documented a wide but subtle range of skin …

Effects Of Temperature And Illumination On Background Matching In Mediterranean Geckos (Hemidactylus Turcicus), Frederic Zaidan, Pamela L. Wiebusch

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The ability to change skin color is a relatively common phenomenon in lizards whose occurrence is often related to crypsis. Field observations suggest that Mediterranean geckos (an often ubiquitous introduced species in many metropolitan areas of the southern United States) have the ability to lighten and darken in response to their background. On light backgrounds, the geckos were typically light pink whereas on dark backgrounds they were typically much darker with a brownish hue to their skin. This study investigated the ability to background match in this species, the main effects of temperature (20, 25, and 30[degrees]C), illumination (total darkness …

Identification Of Factors Affecting Bovine Somatic Cell Nuclear Transfer Efficiency And Characterization Of Transcriptional Profiles Of Nuclear Transfer Embryos And Cotyledons, Kenneth Ivan Aston

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since the production of the first sheep by somatic cell nuclear transfer a great deal of effort has been made to improve efficiency and to understand nuclear reprogramming mechanisms. Unfortunately efficiency remains low, and nuclear reprogramming mechanisms remain uncharacterized. The objectives of this research were to identify factors associated with somatic cell nuclear transfer efficiency and to analyze the transcriptome of blastocyst-stage clone and control embryos and cotyledonary tissue in an effort to elucidate mechanisms responsible for the low developmental efficiency and high post-implantation losses.

The experiments reported here identify factors including oocyte source and timing of activation following nuclear …

Breeding Behavior And Space Use Of Male And Female Mule Deer: An Examination Of Potential Risk Differences For Chronic Wasting Disease Infection, Leslie R. Mcfarlane

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The dynamics of pathogen and host relationships relative to disease transmission in wildlife populations are important ecological processes to understand, particularly since spatial dynamics of disease can be driven by movement, behavior, and dispersal of animals. Chronic Wasting Disease (CWD) is an example of this important interface, where little is known regarding origin of the disease or routes of transmission. Surveillance data for CWD in free-ranging mule deer indicates that breeding-age male deer have 2-4 times higher prevalence rates than females or younger age males. In an effort to understand differences that might increase risk for exposure to CWD infective …

Biochemical Study Of Endonuclease V And Its Application In Mutation Scanning, Honghai Gao

All Dissertations

The integrity of the genetic information encoded by DNA is essential to all living organisms, yet the reactive bases of DNA are constantly attacked by endogenous and exogenous agents resulting in as many as one million individual molecular lesions per cell per day. Excessive DNA damage or deficiency in DNA repair enzymes may cause cancer, premature aging, and neurodegenerative diseases.
Endonuclease V (Endo V) is a DNA repair enzyme which can recognize all four types of DNA deamination products, specifically, uracil, hypoxanthine, xanthine and oxanine. It was also shown that endo V can recognize mismatches. We screened about 60 mutants …

Stoichiometric Controls Of Mercury Dilution By Growth, Roxanne Karimi, Celia Y. Chen, Paul C. Pickhardt, Nicholas S. Fisher, Carol L. Folt

Dartmouth Scholarship

Rapid growth could significantly reduce methylmercury (MeHg) concentrations in aquatic organisms by causing a greater than proportional gain in biomass relative to MeHg (somatic growth dilution). We hypothesized that rapid growth from the consumption of high-quality algae, defined by algal nutrient stoichiometry, reduces MeHg concentrations in zooplankton, a major source of MeHg for lake fish. Using a MeHg radiotracer, we measured changes in MeHg concentrations, growth and ingestion rates in juvenile Daphnia pulex fed either high (C:P = 139) or low-quality (C:P = 1317) algae (Ankistrodesmus falcatus) for 5 d. We estimated Daphnia steady-state MeHg concentrations, using a …

Effect Of Calcium Channel Antagonists And Sex On Bone Metabolism In Aged Brown Norway Rats, Brent Kidd

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science & Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Brent Kidd on April 19, 2007.

Differential Effects Of Hunting On Pre-Dispersal Seed Predation And Primary And Secondary Seed Removal Of Two Neotropical Tree Species, Noelle G. Beckman, Helene C. Muller-Landau

Biology Faculty Publications

Many of the mammals undergoing drastic declines in tropical forests worldwide are important seed dispersers and seed predators, and thus changes in mammal communities due to hunting will affect plant recruitment. It has been hypothesized that larger-seeded species will suffer greater reductions in seed removal and thus greater increases in predispersal seed predation than smaller-seeded species. We compared primary and secondary seed removal and predispersal seed predation of two tree species between hunted and nonhunted sites in Central Panama. Seeds of Oenocarpus mapora (Arecaceae) are 16-times greater in size than those of Cordia bicolor (Boraginaceae). We quantified primary seed removal …

The Plight Of Large Animals In Tropical Forests And The Consequences For Plant Regeneration, S. Joseph Wright, Kathryn E. Stoner, Noelle Beckman, Richard T. Corlett, Rodolfo Dirzo, Helene C. Muller-Landau, Gabriela Nuñez-Iturri, Carlos A. Peres, Benjamin C. Wang

Biology Faculty Publications

We introduce a special section that addresses the bushmeat or wild meat crisis, its direct impact on game species, and its indirect impact on plants in tropical forests.

Ua66 2007 Student Awards Ceremony, Wku Ogden College Of Science & Engineering

WKU Administration Documents

Program recognizing Ogden College students with brief list of activities for each student.

Genomic And Expression Analysis Of Multiple Sry Loci From A Single Rattus Norvegicus Y Chromosome, Monte E. Turner, Carey Martin, Almir S. Martins, Jeffrey Dunmire, Joel Farkas, Daniel L. Ely, Amy Milsted

Biology Faculty Research

Background: Sry is a gene known to be essential for testis determination but is also transcribed in adult male tissues. The laboratory rat, Rattus norvegicus, has multiple Y chromosome copies of Sry while most mammals have only a single copy. DNA sequence comparisons with other rodents with multiple Sry copies are inconsistent in divergence patterns and functionality of the multiple copies. To address hypotheses of divergence, gene conversion and functional constraints, we sequenced Sry loci from a single R. norvegicus Y chromosome from the Spontaneously Hypertensive Rat strain (SHR) and analyzed DNA sequences for homology among copies. Next, to determine …

First Slaty-Backed Gull For Minnesota, Philip C. Chu

Biology Faculty Publications

No abstract provided.

Associating Larvae And Adults Of Chinese Hydropsychidae Caddiflies (Insecta:Trichoptera) Using Dna Sequences, Xin Zhou, Karl M. Kjer, John C. Morse

Publications

The utility of hydropsychid (Trichoptera:Hydropsychidae) caddisfly larvae for freshwater biomonitoring has been demonstrated, but the major impediment to its implementation has been the lack of species-level larval descriptions and illustrations. A rapid and reliable molecular protocol that also uses morphology is proposed because conventional approaches to associating undescribed larvae with adults have been slow and problematic. Male adults were identified before DNA sequence analyses were used. These identifications established morphospecies boundaries that were mapped on phylograms constructed from 2 independent gene fragments: mitochondrial cytochrome c oxidase subunit I (COI) and large subunit (28S) nuclear ribosomal DNA expansion fragment D2 (D2). …

Shark Bay Prawn And Scallop Fisheries. Draft Review Report, Department Of Fisheries Western Australia

Fisheries Management Papers

In recent times, the Department of Fisheries has received representations from both sectors about the ongoing interaction of the fisheries and their respective management settings. As a result, a decision was made to comprehensively review the fisheries, taking into account matters of fishery sustainability and gear interactions, together with industry economics and market considerations. The review has also addressed research requirements to ensure an appropriate scientific basis for decision-making into the future.

Climate, Hydrologic Disturbance, And Succession: Drivers Of Floodplain Pattern, Diane C. Whited, Mark S. Lorang, Mary J. Harner, F. Richard Hauer, John S. Kimball, Jack Arthur Stanford

Biological Sciences Faculty Publications

Floodplains are among the world's most threatened ecosystems due to the pervasiveness of dams, levee systems, and other modi. cations to rivers. Few unaltered floodplains remain where we may examine their dynamics over decadal time scales. Our study provides a detailed examination of landscape change over a 60-year period ( 1945 - 2004) on the Nyack floodplain of the Middle Fork of the Flathead River, a free-flowing, gravel-bed river in northwest Montana, USA. We used historical aerial photographs and airborne and satellite imagery to delineate habitats ( i.e., mature forest, regenerative forest, water, cobble) within the. oodplain. We related changes …

An Extended Stem-Loop 1 Is Necessary For Human Immunodeficiency Virus Type 2 Replication And Affects Genomic Rna Encapsidation, Jean-Marc Lanchy, J. Stephen Lodmell

Biological Sciences Faculty Publications

Genomic RNA encapsidation in lentiviruses is a highly selective and regulated process. The unspliced RNA molecules are selected for encapsidation from a pool of many different viral and cellular RNA species. Moreover, two molecules are encapsidated per viral particle, where they are found associated as a dimer. In this study, we demonstrate that a 10-nucleotide palindromic sequence (pal) located at the 3' end of the psi encapsidation signal is critical for human immunodeficiency virus type 2 (HIV-2) replication and affects genomic RNA encapsidation. We used short-term and long-term culture of pal-mutated viruses in permissive C8166 cells and their phenotypic reversion …

A Sine-Based Dichotomous Key For Primate Identification, Jacquelyn W. Zimmerman

Honors Capstones

No abstract provided.

Filling Key Gaps In Population And Community Ecology, Anurag A. Agrawal, David D. Ackerly, Fred Adler, A. Elizabeth Arnold, Carla Cáceres, Daniel F. Doak, Eric Post, Peter J. Hudson, John L. Maron, Kailen A. Mooney, Mary Power, Doug Schemske, Jay Stachowicz, Sharon Strauss, Monica G. Turner, Earl Werner

Biological Sciences Faculty Publications

We propose research to fill key gaps in the areas of population and community ecology, based on a National Science Foundation workshop identifying funding priorities for the next 5–10 years. Our vision for the near future of ecology focuses on three core areas: predicting the strength and context-dependence of species interactions across multiple scales; identifying the importance of feedbacks from individual interactions to ecosystem dynamics; and linking pattern with process to understand species coexistence. We outline a combination of theory development and explicit, realistic tests of hypotheses needed to advance population and community ecology.

Direct And Interactive Effects Of Enemies And Mutualists On Plant Performance: A Meta-Analysis, William F. Morris, Ruth A. Hufbauer, Anurag A. Agrawal, James D. Bever, Victoria A. Borowicz, Gregory S. Gilbert, John L. Maron, Charles E. Mitchell, Ingrid M. Parker, Alison G. Power, Mark E. Torchin, Diego P. Vázquez

Biological Sciences Faculty Publications

Plants engage in multiple, simultaneous interactions with other species; some (enemies) reduce and others (mutualists) enhance plant performance. Moreover, effects of different species may not be independent of one another; for example, enemies may compete, reducing their negative impact on a plant. The magnitudes of positive and negative effects, as well as the frequency of interactive effects and whether they tend to enhance or depress plant performance, have never been comprehensively assessed across the many published studies on plant–enemy and plant–mutualist interactions. We performed a meta-analysis of experiments in which two enemies, two mutualists, or an enemy and a mutualist …

A Cautionary Tale: Cryptic Sexual Size Dimorphism In A Socially Monogamous Passerine, Michael T. Murphy

Biology Faculty Publications and Presentations

Among socially monogamous birds, standard metrics suggest that males are only ∼5% larger than females. An untested assumption is that, with the exception of reproductive systems, males and females are scaled mirror images of one another. I used external morphological and skeletal data, and information on muscle mass and organ size, to test this assumption in a population of breeding Eastern Kingbirds (Tyrannus tyrannus). Male and female Eastern Kingbirds exhibited no differences in body mass or standard measures of size, except in a longer (∼6%) wing chord and tail in males. However, keel length, a character rarely measured …

The Tadpole Of Leptodactylus Notoaktites Heyer, 1978 (Anura, Leptodactylidae), Rafael O. De Sá, José A. Langone, Magno V. Segalla

Biology Faculty Publications

The external morphology and oral disc of the tadpole of Leptodactylus notoaktites Heyer, 1978, are described and illustrated for Gosner’s stage 33. The internal oral anatomy was analyzed under SEM at Gosner’s stage 36 whereas chondrocranial anatomy is reported for Gosner’ stage 38. The morphology of this tadpole is compared with those available for other species of the L. mystaceus complex. The overall characteristics do not depart from those known for the genus Leptodactylus and they particularly agree for those of the fuscus species group. The labial tooth row formula is 2(2)/3.