Biology Commons^™

Ornamentation, Behavior, And Maternal Effects In The Female Northern Cardinal, Caitlin Winters

Master's Theses

This study seeks to understand the relationship between ornamentation, maternal effects, and behavior in the female Northern Cardinal (Cardinalis cardinalis). Female birds possess ornaments that indicate a number of important known aspects of quality and are usually costly to maintain. However, the extent to which female specific traits, such as maternal effects, are indicated is less clear. It is predicted by the Good Parent Hypothesis that this information should be displayed through intraspecific signal communication. Specifically, androgens and carotenoids are of interest in this study because both are linked to ornamentation, and are also important egg components that …

Feeding Selectivity And Habitat Usage Of Esox Americanus, Scott Richard Clark

Master's Theses

Patterns of piscine prey selection and habitat usage of Esox americanus were assessed through a series of field and experimental studies. Although few detailed studies exist on the foraging behavior and habitat usage of E. americanus, throughout its range it may be an important trophic component in maintaining fish assemblage structure in many lower order streams. Across 17 sampled streams, the presence of E. americanus among reaches within streams was found to be strongly correlated with increasing levels of habitat complexity. Reaches occupied by E. americanus featured increased amounts of in-stream physical structure, increased variability in stream width and …

Diet And Feeding-Related Morphometrics Of The Blackstripe Topminnow, Fundulus Notatus, In Allotropic And Syntopic Populations With The Blackspotted Topminnow, Fundulus Olivaceus, Charles Michael Champagne

Master's Theses

The Fundulus notatus species complex consists of three described species: F. notatus, F. olivaceus and F. euryzonus. Both F. notatus and F. olivaceus have broad overlapping ranges with many populations being found within and outside of contact zones. Contact zones are generally found in midreaches with F. olivaceus dominating headwaters and F. notatus in larger rivers downstream. Both species share similar ecological niches so the mechanism allowing for stable coexistence in contact zones is unknown. The purpose of this study was to examine variability in diet and feeding morphology of F. notatus in syntopic and allotopic populations across …

Sponges Of The Caribbean: Linking Sponge Morphology And Associated Bacterial Communities, Ericka Ann Poppell

Master's Theses

The ecological and evolutionary relationship between sponges and their symbiotic microflora remains poorly understood, which limits our ability to understand broad scale patterns in benthic-pelagic coupling on coral reefs. Previous research classified sponges into two different categories of sponge microbial associations: High Microbial Abundance (HMA) and Low Microbial Abundance (LMA) sponges. Choanocyte chamber morphology and density was characterized in representatives of HMA and LMA sponges using scanning electron microscopy from freeze-fractured tissue. Denaturing Gradient Gel Elextrophoresis was used to examine taxonomic differences among the bacterial communities present in a variety of tropical sponges. The results supported the hypothesis that choanocyte …

Angiostatin Like Peptides In Milk: Potential Development For Dairy Products Capable Of Cancer Prevention, Erin Stefanutti

Master's Theses

For the past 40 years, antiangiogenic approaches have been of major interest in the development of methods to cure and prevent cancer. Angiogenesis, the development of blood vessels from pre-existing vascularization, is essential for cancer growth and spread of metastasis through the delivery of nutrients and oxygen essential to sustain the metabolic activity of these malignant cells. Blocking access to blood will cause cancerous cells to assume a dormant state creating inactive micro-tumors innocuous to the host. Angiostatin, the internal fragment of the fibrinolytic zymogen plasminogen, has shown great potential in reducing cancer size and number of metastatic colonies in …

Reproductive Life History Of Fundulus Jenkensi And Comparative Development Of Five Sympatric Fundulid Species, Eric Thomas Lang

Master's Theses

Fundulus jenkinsi is recognized federally and within the state of Mississippi as a Species of Concern. Little is known about the life history of this coastal killifish, but a detailed reproductive histology study of F. jenkinsi and a diagnostic key of the early life stages of select members of Fundulidae can provide the foundation needed to accurately identify it and quantify reproductive parameters in this rare species in need of conservation. Monthly gonadosomatic index (GSI) of male and female F. jenkinsi were documented, and spawning phases and oocyte stages were examined using reproductive histology. In addition, various stages of …

Temperature Affects Adhesion Of The Acorn Barnacle (Balanus Amphitrite), Laurel A. Johnston

Master's Theses

Biofouling is the accumulation of sessile marine organisms, such as algae, tube worms and barnacles on man-made substrata and has negative economic and ecological implications. Ship hulls are readily fouled, which significantly increases drag while decreasing ship fuel efficiency when moving through water. Fouled hulls have also become important vectors of invasive species. These problems are minimized when hulls are painted with a toxic anti-fouling or non-toxic foul-release coating. Due to recent restrictions of anti-fouling paint use, research and development of non-toxic alternatives has increased.

Novel hull coating efficiency is often quantified by the critical removal stress value of barnacles …

The Presence Of Micropterus Salmoides (Largemouth Bass) Influences The Populations Of Rana Draytonii (California Red-Legged Frog) And Pseudacris Regilla (Pacific Treefrog) In Two Ponds In Santa Barbara County, California, Kenneth Lee Gilliland

Master's Theses

Alien fish have been implicated in the decline of Rana draytonii (California red-legged frog) and Pseudacris regilla (Pacific treefrog) populations. Micropterus salmoides (largemouth bass) is a common sport fish that has been introduced into the sympatric range of these two anuran species; however, no studies have investigated the individual influence that this alien fish has on these two species. I conducted M. salmoides control or eradication experiments during a four year study in two ponds within the Transverse Mountain Range of Santa Barbara County, California. Changes in the densities of all life stages of R. draytonii and P. regilla were …

Hcnabc Gene Expression In The Soil Bacterium Pseudomonas Putida Ath2-Iri/9 Under Various Culture And Rhizosphere Conditions, Myrna May Biswas

Master's Theses

Pseudomonas putida ATH2-1RI/9, a bacterium that colonizes plant roots, can suppress weed seedling growth of velvetleaf by producing hydrogen cyanide in the rhizosphere. The operon hcnABC constitutively expresses HCN synthase, an enzyme which catalyzes glycine to form carbon dioxide and hydrogen cyanide, a secondary metabolite. Cyanogenesis is influenced by several environmental factors including iron, phosphate, and oxygen-limiting conditions. This study used a hcnABC::luxAB gene fusion in Pseudomonas putida ATH2-1RI/9 involving the insertion of a promoterless luxAB gene into the hcnABC operon, which results in bacterial luciferase expression instead of HCN synthase. Bioluminescence by this reporter strain was compared to cyanide …

Courtship And Copulation In Glaucous-Winged Gulls, Larus Glaucescens, Kelly M. Mcwilliams

Master's Theses

Using video recordings and scan counts, I examined the occurrence, sequences, and durations of behavior and environmental factors associated with courtship and copulation in glaucous-winged gulls, Larus glaucescens. Males and females in a pair had equivalent pre- and post-Mount behavior occurrences and durations. The main courtship sequence was Head Toss -- Courtship Beg/Respond -- Mounted/Mount, and felames appeared to initiate transitions between these pre-Mount behaviors. More Mounts occurred during the egg-laying stage of the breeding season, but copulation duration, wing-flag duration, and cloacal contacts per copulation showed no significant differences across sampling periods. Poisson analysis showed no significant grouping …

Dissolved Organic Matter Influences The Timing Of Embryonic Development Of The Purple Sea Urchin, Strongylocentrotus Purpuratus., Corbin J. Hodges

Master's Theses

Marine dissolved organic matter (DOM) comprises one of the largest carbon reservoirs on earth and has long been considered a potential energy source for marine invertebrates. The importance of DOM transport has been adequately demonstrated for unicellular organisms, where DOM can meet 100% of an organisms energy needs, but the effects of DOM uptake for marine metazoans are less well understood. In this study, three general areas involving the influence of DOM transport to marine invertebrates were explored. First, we assessed the effects of using seawater exposed to high intensity ultraviolet radiation (UVR) on the study organism; embryos of the …

Sex And Microhabitat Influence The Allocation Of Mycosporine-Like Amino Acids To Tissues In The Purple Sea Urchin, Strongylocentrotus Purpuratus, Sarah A. Gravem

Master's Theses

Field surveys of Strongylocentrotus purpuratus demonstrated that concentrations of natural sunscreens, mycosporine-like amino acids (MAAs), were higher in females than males for both gonadal and epidermal tissues, increased in ovaries as spawning season approached, and were influenced by the sea urchins’ microhabitat. Sea urchins occupying burrows, or “pits”, had lower concentrations of MAAs than those outside pits, suggesting a trade-off between physical and UV protection. Overall, UV irradiance did not influence MAA accumulation in gonadal tissues. However, males increased their allocation of MAAs to epidermal tissues in the microhabitat with the highest irradiance. Relative concentrations of individual MAAs were similar …

Impact Of Weed Management Practices On Grapevine Growth, Yield Components, Plant And Arthropod Abundance, And Carabid Seed Predation In Paso Robles Vineyard, Paolo Sanguankeo

Master's Theses

In the Central Coast of California, USA, wine grape growers are making efforts to identify weed control practices that promote biodiversity in their vineyards while maintaining yields. A field study was conducted in Paso Robles, CA in 2006 and 2007 evaluating the effect on Zinfandel grape-vine growth and production, groundcover plant, and ground dwelling arthropod communities of five weed control practices: 1) flumioxazin, 2) simazine, 3) cultivation, 4) cover crop, and 5) untreated control.

The herbicide treatments had the lowest weed biomass followed by the cultivation, being approximately 10 and 2 times lower than the weed biomass of either the …

Mimicking Fire For Post-Mining Restoration Success, Katherine M. Wilkin

Master's Theses

This study is based at Rocky Canyon Quarry (RCQ), a 200-acre granite aggregate open-pit quarry with chaparral-dominated plant communities located in San Luis Obispo County, CA. At RCQ, the Surface Mining and Reclamation Act (SMARA) of 1975 was interpreted as restoring the landscape to native plant communities. Native plant community restoration projects have occurred there since 1993 through cooperation with California Polytechnic State University Biology Department in San Luis Obispo, CA. I evaluated past restoration at RCQ and researched new techniques to improve chaparral restoration based on the natural processes of fire.

Chaparral is an important fire-dominated plant community within …

Exposure To Ultraviolet Radiation Causes Proteomic Changes In Embryos Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Joseph Paul Campanale

Master's Theses

The amount of solar ultraviolet radiation (UVR, 290-400 nm) reaching Earth’s surface is increasing due to ozone depletion and global climate change. Embryos of the purple sea urchin, Strongylocentrotus purpuratus, provide an ideal system for examining how UVR affects developing marine organisms and cells in general. To model the protein-mediated cell cycle response to UV-irradiation, six batches of S. purpuratus embryos were exposed to UVR, monitored for delays in the first mitotic division and examined for global proteomic changes. Embryos from each batch were exposed to or protected from artificial UVR for 25 or 60 min. Embryos treated with …

The Relationship Between Plasma Steroid Hormone Concentrations And The Reproductive Cycle Of The Northern Pacific Rattlesnake, Crotalus Oreganus, Craig Michael Lind

Master's Theses

To gain a better understanding of the role of steroid hormones in vertebrate reproduction, we quantified steroid hormone concentrations in a free ranging population of the Northern Pacific rattlesnake, Crotalus oreganus. Plasma steroid hormone concentrations were quantified for both male and female snakes throughout the active season (Mar-Oct). We measured testosterone (T), 5α-dihydrotestosterone (DHT), and corticosterone (B) concentrations in male and female snakes. 17β-estradiol (E2) and progesterone (P) were measured in females only. We also observed breeding behaviors (e.g. consortship, courtship, and copulation) in the field and measured testis and follicle size in male and female snakes from museum collections. …

Investigating The Roles Of Ndj1 And Tid1 In Distributive Segregation Using Non-Exchange Chromosomes, Jonathan V. Henzel

Master's Theses

Meiosis is a specialized cell division that leads to a reduction of ploidy in sexually reproducing organisms through segregation of homologous chromosomes at the first meiotic division. Improper segregation of chromosomes during meiosis results in anueploidy, which is usually fatal during embryonic development. The meiotic process is therefore tightly regulated. Typically, proper segregation of homologs at meiosis I requires pairing of homologous chromosomes, followed by crossover recombination between homologs. Crossovers enable proper chromosomal segregation during the first meiotic division in part by establishing tension in the meiotic spindle. However, in the absence of crossovers, some cells maintain the ability to …

Spatial, Seasonal, And Size-Dependent Variation In The Diet Of Sacramento Pikeminnow In The Main Stem Of Chorro Creek, Central Coast California, Brian G. Dugas

Master's Theses

This study examined the diet composition of ninety-nine Sacramento pikeminnow (150-410 mm [5.9-16 in] fork length [FL]) collected from the upper and lower main stem of Chorro Creek, Morro Bay Watershed, California in 2006. The goal of this study was to characterize the spatial and seasonal variability in the diet of Sacramento pikeminnow within Chorro Creek and to determine what proportion of the diet is represented by rainbow trout (Oncorhynchus mykiss) and their anadromous form (steelhead). Prey was identified in 88% of the samples collected in the early season and 84% of the samples collected in the late season. Fish …

Effects Of Experience On Maternal Behavior In Belding’S Ground Squirrels (Spermophilus Beldingi): Older And Wiser?, Mikael Langner

Master's Theses

Maternal behavior is an important behavior because it influences whether or not raising one’s offspring is successful. Maternal experience is positively correlated with successful maternal behavior. This association is evident when comparing first-time mothers with mothers who have prior experience raising young. Life experience not related to raising young can also positively influence maternal behavior. In this work, the hypothesis that is tested is whether or not maternal experience enhances the ability of a female to assess the threat level of a situation. The model species used to conduct the study is the Belding ground squirrel (Spermophilus beldingi), …

An Investigation Of The Changes Of Species Richness And Distribution Of The Unionidae (Bivalvia: Molusca) Within The Pamunkey Watershed, William Robert Lees

Master's Theses

A survey of the Unionidae within the Pamunkey Watershed was conducted to investigate changes in distribution and species richness compared to a previous survey (Riddick, 1973) conducted over 30 years ago. Species richness decreased from 10 species in the previous survey to four species in the present survey. Notable increases of species richness were found in the upper South Anna and the lower North Anna regions, while sizable decreases were found in the lower South Anna and the upper and middle regions of the Pamunkey River. Regression analyses and t-tests comparing mussel survey data with habitat parameters were conducted to …

The Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry

Master's Theses

The project was undertaken with three main goals in mind: to provide as current and complete an account as possible of the flora of Powhatan County in the form of an annotated checklist; to integrate the information obtained from the inventory into phytogeographical and ecological generalizations currently being developed for the state of Virginia; and, to report any significant or anomalous discoveries. There is no previous county-wide inventory of plant diversity for Powhatan County. However, Corcoran (1981) published a list of plants from the Jones and Mill Creek watershed located in the Fine Creek Mills area of northeastern Powhatan.

Cytokine Expression By T. Helper Cells Responding To Stress, Dina Zanetti

Master's Theses

Stress causes alterations to the immune system. These alterations have lead to increased susceptibility to antigens. The present study explores shifts in T helper (TH) cell balance (TH1 and TH2), through their cytokine expression. This study was performed in three phases, and focused mainly on animals subjected to a 10 day a chronic unpredictable stress paradigm. Phase one used ELISAs to confirm the cytokine profile produced from TH 1 and TH2 murine cell-lines. Phase two used SDS PAGE and Western Immunoblotting to show that splenocytes from Long Evan's Hooded rats subjected to the stress paradigm, had decreased in intercellular in …

The Status Of Leptodactylus Validus As A Single Taxon And Its Relationship To Letptodactylus Pallidirostris, Kenneth Christopher Yanek

Master's Theses

Leptodactylus validus exhibits an unusual distribution inhabiting Trinidad, Tobago, and the Lesser Antilles, but not the mainland of South America. This distribution is inconsistent with other distribution patterns observed for these islands. Although slight variation in adult morphology has been observed among the island populations, call data suggest the presence of a single species. Calls of Leptodactylus pallidirostris from Venezuela suggested that this taxon might be conspecific with L. validus. Herein sequence data from the 12S and 16S mt rRNA genes were collected and analyzed in order to address: 1.) whether more than one species is represented within L. validus, …

Acalypha Deamii : Distribution East Of The Appalachians And Comparative Studies Of Reproductive Anatomy, Patricia A. Truman

Master's Theses

Acalypha deamii (Euphorbiaceae), once thought restricted to flood plains of the Ohio and mid-Mississippi River systems, is now documented from similar habitats in Virginia, Maryland, and West Virginia along the James, Potomac, Rappahannock, Roanoke (Staunton), and Shenandoah rivers. This species is recognized by two-carpellate gynoecia, large seeds, and the routine occurrence of allomorphic flowers and fruits, features sporadically found within this large genus. In addition to documenting the newly recognized range extension of Acalypha deamii, this thesis also investigates the nature of its allomorphic reproductive structures. Staminate, pistillate, fruiting, and allomorphic reproductive structures of Acalypha deamii and a closely related …

A Mitochondrial Dna Phylogeny Of The Leptodactylus Fuscus Species-Complex (Leptodactylidae: Anura, Arley Camargo

Master's Theses

Leptodactylus fuscus is a broadly distributed frog species in the Neotropical region. Previous allozymic evidence supported the hypothesis of L. fuscus as a composite of several species. However, morphological and advertisement call data supported the hypothesis of a single-species taxon. These competing hypotheses were evaluated using cladistic analyses of mitochondrial DNA sequences. Fragments of 12S rRNA, 16S rRNA, and ND1 protein-coding genes from 17 populations were sequenced. Phylogenetic analyses were performed using: maximum parsimony, maximum likelihood, and Bayesian analysis. Data sets were analyzed separately and combined. Analyses of the combined data set show four exclusive clades of L. fuscus: …

Storm-Related Suspended Particulate Matter In Little Westham Creek, John R. Jordan

Master's Theses

Properties of a watershed regulate the amount of suspended particulate matter (SPM) in a stream. The present study examined relationships between storm-related SPM and impervious area and tree cover in the suburban watershed of Little Westham Creek, Richmond, Virginia during Summer and early Fall, 1999. SPM concentration, SPM discharge, and turbidity due to clay, silt and sand, and the areas of impervious surface and tree stand cover in the watershed were measured at three sites. SPM concentration, SPM discharge, and turbidity due to clay were greater upstream than downstream. The percentages of watershed area covered by impervious surfaces and tree …

A Quantitative Histological Evaluation Of Articular Cartilage And Regenerated Tissue From A Stress-Shielded In Vivo Model, Jeremy Matthew Kupsco

Master's Theses

Cartilage does not normally repair lesions. Cartilage induced to regenerate experimentally degenerates quickly, perhaps because stresses of articulation do not allow normal extracellular matrix to develop. I examined normal cartilage from dogs, pigs, rabbits, and humans, and canine patellar tissue regenerated in a stress-shielded environment. SEM of canine cartilage after trypsin digestion revealed meshworks of fibrils oriented with a bias normal to the surface in the deep zone, random in the middle zone, and parallel to the surface in the superficial zone. SEM after freeze-fracture revealed tubules of fibrils within the deep zone. I found no evidence of collagen arcades. …

The Role Of Matrix Metalloproteinase-2 In Glioma Invasion, Nicole Danielle Sauers

Master's Theses

Overexpression of matrix metalloproteinase 2, MMP-2, is correlated with highgrade gliomas in vivo. The purpose of this study was to investigate whether MMP-2 overexpression in glioma cell lines leads to increased invasion of glioma cells in vitro. The entire MMP-2 gene was isolated from U87, a glioma cell line known to have high expression of wild-type MMP-2. This :tvIMP-2 gene was inserted in a sense and antisense orientation into pCR3 .1 vectors with a CMV promoter to ensure high levels of expression. Glioma cell lines were transfected with the sense and antisense constructs, as well as the pCR3.l vector alone …

An Ulstrastructural Study Of Acetabularia Acetabulum, Rachel Vangilder

Master's Theses

Calcification within the cell and the cell wall Acetabularia acetabulum, a large single cell alga, is examined through an ultrastructural investigation, electron diffraction, and an elemental analysis. These methods suggest that amorphous calcium carbonate is located adjacent to and within the cell wall. The location of the crystals within and directly outside the cell wall suggests the calcium is obtained from the surrounding environment. Fibrillar structures are seen through SEM in areas where calcification is occurring. This fibrillar material appears to serve as the organic matrix where calcification initiates. Intracellularly electron dense materials is seen in the chloroplasts. This …

Transplanting Broodstock Oysters, Crassostrea Virginica, Onto Reconstructed Oyster Reefs To Increase Spat Recruitment In The Piankatank River, Dawn Chentil Sherwood

Master's Theses

Four oyster reefs were recreated from oyster shells to historical proportions in the Piankatank River from 1993-1995. In December 1997, two of the reconstructed reefs were supplemented with large broodstock oysters from Tangier and Pocomoke Sounds. Since total quantity as well as density ofbroodstock were believed to be limiting factors for recruitment in this river, adding stock was expected to raise spat recruitment. Methods included dive surveys on the reefs, and dredge and patent tong surveys on the natural oyster bars. The recruitment of spat to both reefs and bars was significantly higher in 1998 (p<0.001) than in the previous four years and a positive interaction (p<0.005) was seen between the reefs and the year 1998. Based on these dat~ stock enhancement in the Piankatank River successfully improved recruitment and suggest oyster restoration may be facilitated in other areas of the Chesapeake Bay by strategic enhancement of spawning stocks.