Digital Commons Network^™

Genetic Variability, Pathogen Susceptibility, Subspecies Identity And Conservation Of The Endangered Northern Flying Squirrel (Glaucomys Sabrinus) In Virginia, James Lincoln Sparks Jr.

Theses and Dissertations

I examined the population genetic structure of three known subspecies of Glaucomys sabrinus from Appalachia, Washington State, and two previously unexamined populations from Mount Rogers National Recreation Area (MRNRA) in Southwestern Virginia. Mean FST (0.107) and an AMOVA (P G. sabrinus subspecies populations in the southern Appalachians are genetically differentiated. Glaucomys sabrinus at MRNRA were less inbred than expected. Gene flow, a consensus tree based on Nei's genetic distance, elevated heterozygosity and morphometric data suggest that the MRNRA G. sabrinus population is an intergrade of the two recognized Appalachian subspecies, G. s. fuscus and G. s. coloratus. I compared inbreeding …

Material And Acoustic Properties Of Swimbladders Of Tilapia And Channel Catfish, Mohammed Ali Nawaz

Theses and Dissertations

Acoustically, teleost swimbladders have been considered resonant underwater bubbles. Contrary results indicating that bladders are tuned less sharply than such a bubble have been explained by damping of surrounding fish tissue. Recent findings in toadfish and weakfish, however, suggest that the bladder is a highly damped structure and that the frequency of the fish sounds is deternlined as a forced response to sonic muscle movement rather than by resonance of the bladder. In this study I examined acoustics and material properties of swimbladders in Tilapia (an auditory generalist) and the channel catfish (an auditory specialist). The swimbladder was struck with …

Omnivory By The Small Cosmopolitan Hydromedusa Aglaura Hemistoma, Sean Colin, John H. Costello, William M. Graham, John Higgins Iii

Arts & Sciences Faculty Publications

We investigated the feeding of the small hydromedusa, Aglaura hemistoma (bell diameter < 4 mm), to determine if it occupies a trophic position similar to that of large medusae. Feeding was examined using gut-content analysis of preserved and unpreserved medusae and by analyzing prey-capture events using microvideographic techniques. Analysis of gut contents and prey-capture events revealed that A. hemistoma fed heavily on protistan prey and that it possessed a prey-capture mechanism, specifically a feeding current,that is effective at entraining and capturing protists with low motility. We suggest that many species of small hydromedusae possess prey-capture mechanisms adapted to capture small protistan prey and that many of these small hydromedusae feed omnivorously on microplanktonic prey. The trophic roles of small hydromedusae in different systems are not understood and more studies are needed. However, based on their often high abundances and the cosmopolitan nature, if small hydromedusae …

Flow Patterns Generated By Oblate Medusan Jellyfish: Field Measurements And Laboratory Analyses, John O. Dabiri, Sean Colin, John H. Costello, Morteza Gharib

Arts & Sciences Faculty Publications

Flow patterns generated by medusan swimmers such as jellyfish are known to differ according the morphology of the various animal species. Oblate medusae have been previously observed to generate vortex ring structures during the propulsive cycle. Owing to the inherent physical coupling between locomotor and feeding structures in these animals, the dynamics of vortex ring formation must be robustly tuned to facilitate effective functioning of both systems. To understand how this is achieved, we employed dye visualization techniques on scyphomedusae (Aurelia aurita) observed swimming in their natural marine habitat. The flow created during each propulsive cycle consists of …

Prorocentrum Minimum(Clone Exuv) Is Nutritionally Insufficient, But Not Toxic To The Copepod Acartia Tonsa, Hans G. Dam, Sean Colin

Arts & Sciences Faculty Publications

This study tested whether the dinoflagellate Prorocentrum minimum is nutritionally insufficient or toxic to the copepod Acartia tonsa. Experiments were carried out with adult female A. tonsa and the P. minimum clone Exuv, both isolated from Long Island Sound. Initially, the functional and numerical responses of A. tonsa feeding on exponentially growing P. minimum cells were characterized. These experiments revealed that A. tonsa readily ingested P. minimum cells, up to the equivalent of 200% of body carbon day⁻¹, but egg production was relatively low, with a maximum egg production rate of 22% of body carbon day …

Conservation Genetics Of Blue-Spotted Salamanders (Ambystoma Laterale) In The Upper Midwest, Jonathan Michael Eastman

Dissertations and Theses @ UNI

Arguably, the primary intention of conservation genetics is to preserve allelic variability within and among populations, because a lack of genetic diversity may adversely effect the viability of a population subjected to variable environmental conditions. The influence of such evolutionary processes as genetic erosion and inbreeding depression may be pronounced for increasingly small and isolated populations. Blue-spotted salamanders (Ambystoma laterale), though widespread and relatively common throughout northeastern North America, are marked by a pair of peripherally isolated populations at the southwestern boundary of the range. These populations are putative relicts of post-glacial isolation and thus provide a model from which …

Interactive Anatomy Online, Jennifer Leopold, Thomas Hoeft, Anne M. Maglia

Computer Science Faculty Research & Creative Works

The scientific community and general public can best take advantage of the benefits of 3D digital reconstructions if they are stored in a Web-accessible, easy-to-access database. We describe MorphologyNet/sup /spl copy// a Web-based digital library of realistic, 3D interactive and customizable images of anatomy currently in development at the University of Missouri-Rolla.

Discovering Cell Mechanisms: The Creation Of Modern Cell Biology, Michael Dietrich

Dartmouth Scholarship

Review of Discovering Cell Mechanisms: The Creation ofModern Cell Biology. Cambridge Studies in Philosophy and Biology. By William Bechtel. Cambridge and New York: Cam-bridge University Press. xii 323 p; ill.; index. ISBN: 052181247X. 2006.

Effect Of Stocking Density On Sunshine Bass (Morone Chrysops X M. Saxatilis) Production And Water Quality At Minor Clark Fish Hatchery, Kentucky, Todd A. Leonard

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the Requirements for the Degree of Master of Science by Todd A. Leonard on December 15, 2004.

Phylogenetic Relationships Of African Microhylid Frogs Inferred From Dna Sequences Of Mitochondrial 12s And 16s Rrna Genes, Simon P. Loader, David J. Gower, Kim M. Howell, Nike Doggart, Mark-Oliver Rödel, Barry T. Clarke, Rafael O. De Sá, Bernard L. Cohen, Mark Wilkinson

Biology Faculty Publications

The phylogenetic relationships of microhylid frogs are poorly understood. The first molecular phylogeny for continental African microhylids is presented, including representatives of all subfamilies, six of the eight genera, and the enigmatic hemisotid Hemisus. Mitochondrial 12S and 16S rRNA sequence data were analysed using parsimony, likelihood and Bayesian methods. Analyses of the data are consistent with the monophyly of all sampled subfamilies and genera. Hemisus does not nest within either brevicipitines or non-brevicipitines. It is possibly the sister group to brevicipitines, in which case brevicipitines might not be microhylids. Phrynomantis and Hoplophryne potentially group with non-African, non-brevicipitine microhylids, in …

Exogenous Vasotocin Alters Aggression During Agonistic Exchanges In Male Amargosa River Pupfish (Cyprinodon Nevadensis Amargosae), Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

Pupfishes in the Death Valley region have rapidly differentiated in social behaviors since their isolation in a series of desert streams, springs, and marshes less than 20,000 years ago. These habitats can show dramatic fluctuations in ecological conditions, and pupfish must cope with the changes by plastic physiological and behavioral responses. Recently, we showed differences among some Death Valley populations in brain expression of arginine vasotocin (AVT). As AVT regulates both hydromineral balance and social behaviors in other taxa, these population differences may indicate adaptive changes in osmoregulatory and/or behavioral processes. To test whether AVT is relevant for behavioral shifts …

Distribution Of Chemistry And Sexual Fecundity In The Lichenized-Fungi, Xanthoparmelia Cumberlandia And Xanthoparmelia Coloradoensis On Boulder Mountain, Aquarius Plateau, Ut, Heather Bird Jackson

Theses and Dissertations

Three aspects of Xanthoparmelia cumberlandia and Xanthoparmelia coloradoënsis populations found at two elevations are explored: clustering of secondary chemicals and the resulting implications for taxonomic distinctions, the usefulness of thallus size as an indirect measure of sexual fecundity, and the frequency of sexual reproduction.

First, we use clustering of 46 chemicals produced by X. cumberlandia and X. coloradoënsis to evaluate the adequacy of the current taxonomic distinction between them. Using principal components analysis and UPGMA, we find that the currently recognized species boundaries indicated by the presence of stictic acid in X. cumberlandia and salazinic acid in X. coloradoënsis are …

Monitoring Heart Rate In Drosophila Larvae By Various Approaches, Sameera Dasari, Robin L. Cooper

Biology Faculty Publications

No abstract provided.

Monitoring Carbon Dioxide Production By Drosophila Larvae, Robin L. Cooper, D. Nicholas Mcletchie

Biology Faculty Publications

No abstract provided.

Development And Characterization Of Monoclonal Antibodies Directed Against Tanapox Virus, Michael Franz

Masters Theses

The initial symptoms of a Tanapoxvirus (TPV) infection are indistinguishable from smallpox, which is caused by variola virus (VV). In the post-9/11 area, reagents that can quickly differentiate a TPV infection from smallpox are very desirable, but currently unavailable. Monoclonal antibodies (mAbs) directed specifically against TPV can be used for this purpose. Six mAbs were developed and characterized that specifically bind to TPV infected owl monkey kidney (OMK) cells, but not uninfected cells. The apparent molecular mass of the TPV protein(s) recognized by 5 mAbs were calculated using the Western blot technique. One mAb demonstrated no binding using the Western …

Contractile Responses Of The Rat Gastrocnemius And Soleus Muscles To Isotonic Resistance Exercise, Kris M. Norenberg, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Male rats were divided into control and weight-trained (WT) groups. WT rats performed squattype exercises twice daily, 5 days/wk, for 14 wk. They averaged 36 lifts/day, with an average weight of 555 g. Muscle-to-body weight ratio (mg/g) of the soleus (Sol) was not different from control, but it increased 11 and 6% in the gastrocnemius (Gast) and plantaris, respectively (P < 0.05). The normalized twitch tension of the in situ Sol was elevated by 21%, whereas single-skinned type I fibers from the Sol showed an increased rate constant of tension redevelopment (K_tr) but no other contractile adaptations to WT. In contrast, the Gast type I fibers showed an increase (P < 0.05) in maximal velocity of shortening (25%), peak power (15%), K_tr (18%), and normalized tension (7%). The K_tr and normalized tension of the Gast type IIa fibers increased by …

Monitoring Activity Of Drosophila Larvae: Impedance & Video Microscopy Measures, Ann Simone Cooper, Robin L. Cooper

Biology Faculty Publications

No abstract provided.

Soil Biota Facilitate Exotic Acer Invasions In Europe And North America, Kurt O. Reinhart, Ragan M. Callaway

Biological Sciences Faculty Publications

The primary hypothesis for successful exotic plant invasions is that the invaders have escaped the specialist consumers that control them (Enemy Release Hypothesis). However, few studies have rigorously tested this assertion with biogeographical experiments or considered the effects of soil organisms. We tested the Enemy Release Hypothesis and the enhanced role of mutualisms by comparing density patterns of the North American Acer negundo and European A. platanoides trees in their native and nonnative ranges. Invaders that have escaped their natural enemies are predicted to attain greater densities in nonnative than native ranges. To determine whether interactions with soil biota could …

Bergmann's Clines In Ectotherms: Illustrating A Life-History Perspective With Sceloporine Lizards, Michael J. Angilletta Jr., Peter H. Niewiarowski, Arthur E. Dunham, Adam D. Leache, Warren P. Porter

Biology Faculty Research

The generality and causes of Bergmann's rule have been debated vigorously in the last few years, but Bergmann's clines are rarely explained in the context of life-history theory. We used both traditional and phylogenetic comparative analyses to explore the causes of latitudinal and thermal clines in the body size of the eastern fence lizard (Sceloporus undulatus). The proximate mechanism for larger body sizes in colder environments is delayed maturation, which results in a greater fecundity but a lower survival to maturity. Life-history theory predicts that a higher survivorship of juveniles in colder environments can favor the evolution of a Bergmann's …

Use Of Cre Recombinase And Sb Transposase To Engineer Transgenic Zebrafish, Jie Dong

All-Inclusive List of Electronic Theses and Dissertations

Current transgenesis has become easier for certain species due to the recent development of exogenous non site-specific recombination systems such as Sleeping Beauty (SB) transposon, and site-specific recombination systems such as Cre-loxP. Such recombination systems overcame two major problems caused by conventional transgenesis, position effect and copy number effect. SB is a reconstructed fish transposon that has shown to efficiently insert transgenes into heterologous mammalian chromosomes. The Cre-loxP system is frequently used to delete a given sequence from the genome or to target the integration of foreign DNA. The use of both systems in combination, however, has not yet been …

Neglected Taxonomy Of Rare Desert Fishes: Congruent Evidence For Two Species Of Leatherside Chub, Jerald B. Johnson, Thomas E. Dowling, Mark C. Belk

Faculty Publications

Conservation biologists rely heavily on taxonomy to set the scope for biological monitoring and recovery planning of rare or threatened species. Yet, taxonomic boundaries are seldom evaluated as falsifiable hypotheses that can be statistically tested. Here, we examine species boundaries in leatherside chub (Teleostei, Cyprinidae), an imperiled desert fish native to the Bonneville Basin and upper Snake River drainages of western North America. Recent molecular data hint that this fish could be composed of two distinct taxa that are geographically separated into northern and southern species. To formally test this hypothesis, we evaluated leatherside chub using several different categories of …

Density Effects On Growth, Survival And Diet Of June Sucker (Chasmistes Liorus): A Component Allee Effect In An Endangered Species., David Barrett Gonzalez

Theses and Dissertations

Density-dependence is considered one of the most important regulators of population growth, and it has been documented across a wide variety of species. Typically, population growth rate and components thereof decline with increasing density (i.e., negative density-dependence); however, in species that exhibit high population densities and social behavior, positive density-dependence (i.e., Allee effect) may occur at low density. June sucker, a federally endangered lake sucker endemic to Utah Lake, Utah, USA, occurred historically at high density, and it exhibits coordinated feeding behavior. These characteristics indicate a potential for the existence of an Allee effect at current low population densities. To …

Evidence For And Characterization Of Ca2+ Binding To The Catalytic Region Of Arabidopsis Thaliana Phospholipase Dβ, Xuemin Wang

Biology Department Faculty Works

Most types of plant phospholipase D (PLD) require Ca2+ for activity, but how Ca2+ affects PLD activity is not well understood. We reported previously that Ca2+ binds to the regulatory C2 domain that occurs in the N terminus of the Ca2+-requiring PLDs. Using Arabidopsis thaliana PLDβ and C2-deleted PLDβ (PLDβcat), we now show that Ca2+ also interacts with the catalytic regions of PLD. PLDβcat exhibited Ca2+-dependent activity, was much less active, and required a higher level of Ca2+ than the full-length PLDβ. Ca2+ binding of the proteins was stimulated by phospholipids; phosphatidylserine was the most effective among those tested. Scatchard …

Human Fetal, Cord Blood, And Adult Lymphocyte Progenitors Have Similar Potential For Generating B Cells With A Diverse Immunoglobulin Repertoire, Grant R. Kolar, Takafumi Yokota, Maria Isabel D. Rossi, Swapan K. Nath, J. Donald Capra

Biological Sciences Faculty Research & Creative Works

Several characteristics of the immunoglobulin (Ig) repertoire in fetuses and adults set them apart from each other. Functionally, this translates into differences in the affinity and effectiveness of the humoral immune response between adults and the very young. At least 2 possibilities could explain these differences: (1) fetal and adult lymphocyte progenitors differ significantly in their potential to form a diverse repertoire, and (2) factors extrinsic to the immunoglobulin locus are more influential to the character of the repertoire. To address this, we used nonobese diabetic-severe combined immunodeficient- β2 microglobulin knockout (NOD/SCID/β2m ^-/-) mice reconstituted with human B-cell progenitors …

Sex Differences In Metabolic Rates In Field Crickets And Their Dipteran Parasitoids, Gita R. Kolluru, Mark A. Chappell, Marlene Zuk

Biological Sciences

Sex differences in metabolic rate (MR) can result from dimorphism in the performance of energetically demanding activities. Male crickets (Teleogryllus oceanicus) engage in costly calling and aggressive activity not performed by females. Consistent with this difference, we found higher maximal MR, factorial scope, and fat content in males than females. T. oceanicus song is also costly because it attracts the parasitoid fly Ormia ochracea. Parasitized crickets had reduced maximal MR consistent with a metabolic cost to harboring larvae. This cost was greater for females, either because females invest more heavily into reproduction at the expense of metabolic …

Filarial Genomics, Steven A. Williams

Biological Sciences: Faculty Publications

No abstract provided.

Law, Evolution, And The Brain: Applications And Open Questions, Owen D. Jones

Vanderbilt Law School Faculty Publications

This essay discusses several issues at the intersection of law and brain science. If focuses principally on ways in which an improved understanding of how evolutionary processes affect brain function and human behavior may improve law's ability to regulate behavior. It explores sample uses of such "evolutionary analysis in law" and also raises questions about how that analysis might be improved in the future. Among the discussed uses are: 1) clarifying cost-benefit analyses; 2) providing theoretical foundation and potential predictive power; 3) assessing comparative effectiveness of legal strategies; and 4) revealing deep patterns in legal architecture. Throughout, the essay emphasizes …

Patterns Of Fitness And Fluctuating Asymmetry Across A Broad Hybrid Zone, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

We estimated levels of developmental instability in leaves, as indicated by fluctuating asymmetry (i.e., random deviations from perfect bilateral symmetry), across a broad hybrid zone between two taxa in the Piriqueta caroliniana complex. Previous studies have indicated that this hybrid zone was initiated in southern Florida and has expanded northward. We found that plants from the hybrid zone generally had higher levels of leaf developmental instability than plants from allopatric regions, but the increase in asymmetry was not substantial. Although it is usually assumed that developmental instability is associated with lower fitness, these Piriqueta hybrids from central Florida are similar …

Two Drosophila Suppressors Of Cytokine Signaling (Socs) Differentially Regulate Jak And Egfr Pathway Activities, Jason S. Rawlings, Gabriela Rennebeck, Susan M.W. Harrison, Rongwen Xi, Douglas A. Harrison

Biology Faculty Publications

BACKGROUND: The Janus kinase (JAK) cascade is an essential and well-conserved pathway required to transduce signals for a variety of ligands in both vertebrates and invertebrates. While activation of the pathway is essential to many processes, mutations from mammals and Drosophila demonstrate that regulation is also critical. The SOCS (Suppressor Of Cytokine Signaling) proteins in mammals are regulators of the JAK pathway that participate in a negative feedback loop, as they are transcriptionally activated by JAK signaling. Examination of one Drosophila SOCS homologue, Socs36E, demonstrated that its expression is responsive to JAK pathway activity and it is capable of downregulating …

Skeletal Muscle Fiber Atrophy: Altered Thin Filament Density Changes Slow Fiber Force And Shortening Velocity, Danny A. Riley, J. L. W. Bain, Janell Romatowski, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Single skinned fibers from soleus and adductor longus (AL) muscles of weight-bearing control rats and rats after 14-day hindlimb suspension unloading (HSU) were studied physiologically and ultrastructurally to investigate how slow fibers increase shortening velocity (V₀) without fast myosin. We hypothesized that unloading and shortening of soleus during HSU reduces densities of thin filaments, generating wider myofilament separations that increase V₀ and decrease specific tension (kN/m²). During HSU, plantarflexion shortened soleus working length 23%. AL length was unchanged. Both muscles atrophied as shown by reductions in fiber cross-sectional area. For AL, the 60% atrophy …