Biology Commons^™

The Effect Of The Study Region On Gis Models Of Species Geographic Distributions And Estimates Of Niche Evolution; Preliminary Tests With Montane Rodents (Genus Nephelomys) In Venezuela, Ali Raza

Dissertations and Theses

Various niche-based techniques exist to model a species' potential geographic distribution in a Geographic Information Systems (GIS) framework. These models compare the environmental conditions of localities of a species' occurrence versus those of the overall study region. In addition to uses in areas such as macroecology and conservation biology, this approach has been applied recently to studies of niche evolution and historical biogeography. Definition of the study region is critical for all of these applications but has not been addressed previously. Here, I examine the effect of changes in the extent of the study region on potential distribution models of …

Role Of Drosophila Rap/Fzr (Cdh1) In Retinal Axon Targeting And Its Interactions With Loco, Liprin-A And Ras, Marta Gronska

Dissertations and Theses

The development of the wild type Drosophila compound eye involves stereotypical targeting of photoreceptor axons to the specific layers of the optic ganglion, medulla and lamina, in the third instar larvae. To test the hypothesis that ubiquitin ligases play an important role during retinal axon targeting we have examined the patterns of axon targeting in the developing eye of the retina aberrant in pattern (rap/fzr) mutants. Rap/Fzr is a homolog of mammalian Cdh1, an activator of anaphase promoting complex (APC), an E3 ubiquitin ligase. Previous work has shown that Rap/Fzr is required in cell cycle regulation, glia differentiation and pattern …

Using Geographically Structured Evaluations To Assess Performance And Transferability Of Ecological Niche Models For Species With Many Occurrence Records: A Test Using The Caribbean Spiny Pocket Mouse, Heteromys Anomalus, Aleksandarc Radosavljevi

Dissertations and Theses

No abstract provided.

Does Evolutionary Exposure Mediate Allelopathic Effects?, Nikki Leigh Pisula

Masters Theses

Allelopathy most commonly refers to chemically mediated plant interference, though the effects may range from beneficial to inhibitory. Allelopathy has been suggested as a potential mechanism for invasion success because invasive species may produce allelochemicals that are evolutionarily novel to recipient communities. To test for evolutionary mediation of allelopathy, six target species were grown in a factorial experiment with and without activated carbon or a native allelopathic species, Solidago canadensis (Canada goldenrod). I used activated carbon to remove allelochemicals to separate allelopathic effects from resource competition. The species represented pairs of evolutionary experienced (native - N) and evolutionarily na'ive (non-native …

Effects Of Forest Edges On Population Dynamics In A Successional System, Kimberly Anne Lang

Masters Theses

Abandoned agricultural land is often bound by remnant woodlands which may locally influence successional dynamics. The primary objective of this study was to examine the effect of an old-growth forest edge on plant population dynamics within a successional system. Data from the Buell-Small Succession Study (BSS) in New Jersey were used to analyze population dynamics in relation to the forest edge during the first 50 years of succession following agriculture. It was hypothesized that edge responses would be driven by either differential colonization (dispersal and establishment) or differential performance (increase within plots).

By looking at individual species' edge responses, I …

Soil Variability And Its Influence On Plant Performance, Jeremy R. Klass

Masters Theses

During recorded history, nearly all temperate deciduous forests in eastern North America have seen extensive agricultural land-use conversions. Persistent influences of agricultural disturbance continue to shape the diversity and composition of the plant community long after agriculture has ceased. While some measures of ecosystem functioning may recover relatively quickly from agricultural disturbance, other characteristics such as levels of organic matter, carbon, and phosphorus, may remain different from primary forests for much longer periods. The alteration of the original ecosystem due to agriculture practices has far reaching impacts on biotic and nutrient dynamics along with causing significant shifts in community composition …

Population Ecotoxicology Of The Common Snapping Turtle In Agriculturally Impacted Lotic Ecosystems, Derrick L. Douros

Masters Theses

Anthropogenic impacts on lotic systems, including pollutants, have had both direct and indirect negative effects on the aquatic habitats of the world. Goals of this study are: (1) Quantify atrazine, the atrazine metabolite diaminochlorotriazine (DACT), and glyphosate burdens in common snapping turtle (Chelydra serpentina) tissue from individuals collected within the Embarras River in Coles County, Illinois. (2) Quantify the atrazine, DACT, and glyphosate loads in water from the aquatic habitats in which common snapping turtles reside. (3) Quantify the relative abundance of all turtle species and movement patterns of common snapping turtles in this lotic ecosystem. Hoop nets and modified …

Leptodactylus Savagei, W. R. Heyer, Miriam M. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus savagei are large, the head is as wide as long or usually wider than long, and the hind limbs are moderate in length (Table 1; Heyer and Thompson (2000) provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are not visible externally. Sexually active males have hypertrophied forearms, usually 1 large black spine on each thumb, rarely with 1 large spine and a prepollical bump, and a pair of black chest spines. A pair of entire dorsolateral folds extend anteriorly from at least one_half to full distance from eye to groin, the …

Abiotic Differences Between Green Turtle (Chelonia Mydas) Nests In Natural Beach And Engineered Dunes: Effects On Hatching Success, Martha Balfour

Electronic Theses and Dissertations

Habitat loss is among the biggest threats to conservation worldwide, so habitat restoration plays an increasing role in endangered species management. This is especially true for species with high site fidelity, such as nesting marine turtles. Sand replenishment is commonly used to restore coastal beaches after severe erosion events, and may affect marine turtles and other species that live or reproduce in that habitat. I investigated how abiotic characteristics of sand used in a dune restoration project at Archie Carr National Wildlife Refuge, Florida, affected reproduction of the federally-endangered green turtle (Chelonia mydas). Sand structure and composition can affect egg …

An Assessment Of Sea Turtle Nesting Behavior In Relation To Hurricane- And Restoration-Induced Beach Morphodynamics, Tonya Michele Long

Electronic Theses and Dissertations

Coastal habitats are highly dynamic and vulnerable to landscape-level disturbances such as storms and restoration projects. Along the east coast of Florida these areas are particularly valuable as they provide significant nesting habitat for two sea turtle species, the threatened loggerhead (Caretta caretta) and the endangered green turtle (Chelonia mydas). This coast was heavily impacted by three major hurricanes in 2004 and in some areas by large restoration projects in 2005. Recent remote sensing methods allow for broad evaluation of the shoreline and thus the ability to assess sea turtle nesting habitat at a landscape scale. I collected nesting data …

Geographic Variation In Post-Mating Immune Gene Expression In Drosophila Melanogaster, Cheryl Ann Pinzone

Electronic Theses and Dissertations

An organism's immune response may vary due to pathogen pressure in its environment, as well as due to interactions with other organisms. These factors, along with geographic rules (i.e. Gloger's rule) may influence the geographic distribution of the immune response within populations of a species. Here we use real-time quantitative PCR to measure the immune gene expression in six populations collected along the eastern U.S. of Drosophila melanogaster after mating. Antimicrobial genes did not show significant differences in expression due to location, whereas we did observe differences in anti-fungal and pro-phenoloxidase (anti-macromolecule) related genes. These differences in anti-macromolecule resistance are …

Estimating Diet And Food Selectivity Of The Lower Keys Marsh Rabbit Using Stable Isotope Analysis, Matthew James Gordon

Electronic Theses and Dissertations

Understanding the effect of food abundance on feeding behavior can benefit conservation efforts in many ways, such as to determine whether impacted environments need food supplementation, whether different locations of threatened species contain different food abundances, or whether reintroduction sites are missing key components of a species’ diet. I studied the relationship between feeding behavior and food abundance in the Lower Keys marsh rabbit (Sylvilagus palustris hefneri), an endangered subspecies endemic to the lower Florida Keys. Specifically, my study set out to measure the relative abundance of the primary plants within the natural habitat of the Lower Keys marsh rabbit …

Proteomic And Physiological Responses Of Leopard Sharks (Triakis Semifasciata) To Salinity Change, W. Wesley Dowd, B. N. Harris, J.J. Chech Jr, D. Kültz

Biology Faculty Works

Partially euryhaline elasmobranchs may tolerate physiologically challenging, variable salinity conditions in estuaries as a tradeoff to reduce predation risk or to gain access to abundant food resources. To further understand these trade-offs and to evaluate the underlying mechanisms, we examined the responses of juvenile leopard sharks to salinity changes using a suite of measurements at multiple organizational levels: gill and rectal gland proteomes (using 2-D gel electrophoresis and tandem mass spectrometry), tissue biochemistry (Na+/K+-ATPase, caspase 3/7 and chymotrypsin-like proteasome activities), organismal physiology (hematology, plasma composition, muscle moisture) and individual behavior. Our proteomics results reveal coordinated molecular responses to low salinity …

Chinmo Is A Functional Effector Of The Jak/Stat Pathway That Regulates Eye Development, Tumor Formation, And Stem Cell Self-Renewal In Drosophila, Maria Sol Flaherty, Pauline Salis, Cory J. Evans, Laura A. Ekas, Amine Marouf, Jiri Zavadil, Utpal Banerjee, Erika A. Bach

Biology Faculty Works

The Drosophila STAT transcription factor Stat92E regulates diverse functions, including organ development and stem cell self-renewal. However, the Stat92E functional effectors that mediate these processes are largely unknown. Here we show that chinmo is a cell-autonomous, downstream mediator of Stat92E that shares numerous functions with this protein. Loss of either gene results in malformed eyes and head capsules due to defects in eye progenitor cells. Hyperactivation of Stat92E or misexpression of Chinmo results in blood cell tumors. Both proteins are expressed in germline (GSCs) and cyst stem cells (CySCs) in the testis. While Stat92E is required for the self-renewal of …

Substrate Specificity Of The Tim22 Mitochondrial Import Pathway Revealed With Small Molecule Inhibitor Of Protein Translocation, Deepa V. Dabir

Biology Faculty Works

The TIM22 protein import pathway mediates the import of membrane proteins into the mitochondrial inner membrane and consists of two intermembrane space chaperone complexes, the Tim9-Tim10 and Tim8-Tim13 complexes. To facilitate mechanistic studies, we developed a chemical-genetic approach to identify small molecule agonists that caused lethality to a tim10-1 yeast mutant at the permissive temperature. One molecule, MitoBloCK-1, attenuated the import of the carrier proteins including the ADP/ATP and phosphate carriers, but not proteins that used the TIM23 or the Mia40/ Erv1 translocation pathways. MitoBloCK-1 impeded binding of the Tim9-Tim10 complex to the substrate during an early stage of translocation, …

Locomotion In Response To Shifting Climate Zones: Not So Fast, Martin E. Feder, Theodore Garland Jr., James H. Marden, Anthony J. Zera

School of Biological Sciences: Faculty Publications

Although a species’ locomotor capacity is suggestive of its ability to escape global climate change, such a suggestion is not necessarily straightforward. Species vary substantially in locomotor capacity, both ontogenetically and within/among populations, and much of this variation has a genetic basis. Accordingly, locomotor capacity can and does evolve rapidly, as selection experiments demonstrate. Importantly, even though this evolution of locomotor capacity may be rapid enough to escape changing climate, genetic correlations among traits (often due to pleiotropy) are such that successful or rapid dispersers are often limited in colonization or reproductive ability, which may be viewed as a trade-off. …

An Extra Embryonic Phase In The True Freshwater Crab Sinopotamon Yangtsekiense , H X. Wu, J Xue, Neil Cumberlidge

Journal Articles

No abstract provided.

"A Redescription Of Potamonautes Loveni, A Medically Important Feshwater Crab From Western Kenya And Eastern Uganda, East Africa" , Neil Cumberlidge, Paul F. Clark

Journal Articles

No abstract provided.

"An Extra Embryonic Phase In The True Freshwater Crab Sinopotamon Yangtsekiense Bott" , H X. Wu, J Z. Xue, Neil Cumberlidge

Journal Articles

No abstract provided.

"First Report Of Developmental Changes Inside The Eggs Of The Chinese Freshwater Crab, Sinopotamon Yangtsekiense Bott, 1967, With Comments On Its Evolutionary Significance" , J Xue, Y Liu, Neil Cumberlidge, H X. Wu

Journal Articles

No abstract provided.

Expression Of Hcmv Ie1 In The U87mg Cell Line Augments Resistance To Temozolomide , Richard A. Rovin, Johnathan Lawrence, Justin J. Segula, Robert J. Winn

Journal Articles

INTRODUCTION: Human cytomegalovirus (HCMV) DNA and protein are found in gliomas but not in normal brain or other primary brain tumors. The role of HCMV infection in glioma biology is unclear. While it is unlikely that HCMV infection causes glioma, viral proteins might impart a proliferative and antiapoptotic phenotype that confers a survival advantage. Does this oncomodulation translate into a clinically relevant effect in glioma cells? To answer this question, we compared the response of the U87IE1 and U87MG malignant glioma cell lines to temozolomide. U87IE1 cells are U87MG cells that have been genetically engineered to produce HCMV IE1 protein. …

The Role Of The Feral Pig (Sus Scrofa) As A Disturbance Agent And Seed Disperser In Central Florida's Natural Lands, Camille Rose Brescacin

Electronic Theses and Dissertations

Feral pigs (Sus scrofa) are considered to be among the world’s worst invasive species due to their successful invasion and ecological and economic impact to native and agricultural plants and animals around the world. Feral pigs are significant disturbance agents that destroy plant communities, change soil characteristics, alter nutrient cycling, and create open sites for colonization of both native and non-native plant species through their foraging behavior called rooting. In contrast to native animal disturbances, rooting is a striking feature in the landscape that varies in space, seasonal timing, frequency (number of times rooted), and intensity (depth of rooting). During …

Mechanisms Of Apoptosis In Crustacea : What Conditions Induce Versus Suppress Cell Death?, Michael Menze, Grady Fortner, Suman Nag, Steven Hand

Faculty and Staff Scholarship

Arthropoda is the largest of all animal phyla and includes about 90% of extant species. Our knowledge about regulation of apoptosis in this phylum is largely based on findings for the fruit fly Drosophila melanogaster. Recent work with crustaceans shows that apoptotic proteins, and presumably mechanisms of cell death regulation, are more diverse in arthropods than appreciated based solely on the excellent work with fruit flies. Crustacean homologs exist for many major proteins in the apoptotic networks of mammals and D. melanogaster, but integration of these proteins into the physiology and pathophysiology of crustaceans is far from complete. Whether apoptosis …

Kinetics Of Hedgehog-Dependent Full-Length Gli3 Accumulation In Primary Cilia And Subsequent Degradation, Xiaohui Wen, Cary Lai, Marie Evangelista, Jo-Anne Hongo, Frederic J. De Sauvage, Suzie J. Scales

Biology Faculty Publications

Hedgehog (Hh) signaling in vertebrates depends on intraflagellar transport (IFT) within primary cilia. The Hh receptor Patched is found in cilia in the absence of Hh and is replaced by the signal transducer Smoothened within an hour of Hh stimulation. By generating antibodies capable of detecting endogenous pathway transcription factors Gli2 and Gli3, we monitored their kinetics of accumulation in cilia upon Hh stimulation. Localization occurs within minutes of Hh addition, making it the fastest reported readout of pathway activity, which permits more precise temporal and spatial localization of Hh signaling events. We show that the species of Gli3 that …

Acoel And Platyhelminth Models For Stem-Cell Research, A. E. Bely, James M. Sikes Ph.D.

Biology Faculty Publications

Acoel and platyhelminth worms are particularly attractive invertebrate models for stem-cell research because their bodies are continually renewed from large pools of somatic stem cells. Several recent studies, including one in BMC Developmental Biology, are beginning to reveal the cellular dynamics and molecular basis of stem-cell function in these animals.

See research article http://www.biomedcentral.com/1471-213X/9/69.

Adult somatic stem cells can play critical roles in postembryonic developmental processes such as tissue renewal, growth, repair, and regeneration [1]. Understanding how such cells are maintained and produce differentiated progeny is thus of general interest in developmental biology, in addition to …

Structural Investigation Of Atp-Utilizing Enzymes: Structures Involved In H+ Homeostasis And The Proliferation Of Hormone-Dependent Cancers, Zacariah Louis Hildenbrand

Open Access Theses & Dissertations

ATP is a multifunctional nucleotide considered to be the "molecular unit of currency" of intracellular energy transfer. ATP is utilized ubiquitously for the transport of chemical energy within the cell in addition to acting as a substrate in the regulation of many metabolic and signaling transduction pathways such as kinase-mediated signaling cascades. Interestingly, the functional mechanisms of many enzymes require the binding of ATP to trigger key structural and conformational changes that ultimately result in enzyme-directed catalysis. Two of the most omnipresent ATPases within the cell include the V-ATPase rotary proton pump and the Hsp90 protein-folding chaperone. Structural and biochemical …

Identification Of A Novel Cytokine Inducible Stat5 Phosphoserine Site (Ps193) That Positively Regulates Its Transcriptional Activity And Is Found Constitutively Activated In Certain Hematopoietic Cancers, Abhisek Mitra

Open Access Theses & Dissertations

Hematological malignancies such as leukemia and lymphoma, can develop from aberrant changes in the cell signaling molecules to drive their uncontrolled cellular proliferation and differentiation. Activation, maturation, expansion and differentiation of T cells are critically regulated by the dynamics of various transcription factors activated by a variety of cytokines. Additionally, multiple effector molecules that mediate these T cells dependent signals include the JAK (Janus Kinase)-STAT (Signal transducer and activator of transcription) cascade. These signaling proteins are activated in response to a broad array of cytokines. Constitutively activated JAKs and STATs have been described in several T cell malignancies. A growing …

Systematics Of The Genus Ptychadena Boulenger, 1917 (Anura: Ptychadenidae) From Democratic Republic Of The Congo, Katrina Marie Weber

Open Access Theses & Dissertations

This thesis increases the scope of previous phylogenetic analyses that revealed high levels of genetic differentiation within the anuran genus Ptychadena. Herein, I increase sampling of Central African populations of Ptychadena by over six times to examine their relationships to other African populations and to search for cryptic species. This study represents the most comprehensive molecular phylogeny of Ptychadena to date. A total of three mitochondrial (12S, 16S, and cyt b) and two nuclear (RAG1 and rhodopsin) genes were sequenced for 67 specimens of Ptychadena. Maximum parsimony, maximum likelihood, and Bayesian analyses were conducted. These analyses revealed …

Teaching Species, Mark W. Ellis, Paul G. Wolf

Biology Faculty Publications

A clear understanding of the term "species" is fundamental to the subject of evolution. However, introductory textbooks often fail to address this topic until one of the later chapters, after having used the term species in all preceding chapters. Furthermore, definitions of terms critical to a clear understanding of this subject are often vague or absent in chapters on species concepts. We feel the popular notion of a "species problem" has been unnecessarily inflated by this less-than-effective educational approach. Clearly addressing this essential subject at the beginning of a course on evolution will prepare students to learn the details and …

Complete Plastome Sequences Of Equisetum Arvense And Isoetes Flaccida: Implications For Phylogeny And Plastid Genome Evolution Of Early Land Plant Lineages, K. G. Karol, K. Arumuganthan, J. L. Boore, A. M. Duffy, K. D. E. Everett, J. D. Hall, S. K. Hansen, J. V. Mandoli, D. F. Mandoli, B. D. Mishler, R. G. Olmstead, K. S. Renzaglia, Paul G. Wolf

Biology Faculty Publications

Background Despite considerable progress in our understanding of land plant phylogeny, several nodes in the green tree of life remain poorly resolved. Furthermore, the bulk of currently available data come from only a subset of major land plant clades. Here we examine early land plant evolution using complete plastome sequences including two previously unexamined and phylogenetically critical lineages. To better understand the evolution of land plants and their plastomes, we examined aligned nucleotide sequences, indels, gene and nucleotide composition, inversions, and gene order at the boundaries of the inverted repeats. Results We present the plastome sequences of Equisetum arvense, a …