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Mitochondrial Genome Evolution In The Metazoa: Insights From Class Hexactinellida (Phylum Porifera) And Phylum Cnidaria, Karri Michelle Haen 2010 Iowa State University

Mitochondrial Genome Evolution In The Metazoa: Insights From Class Hexactinellida (Phylum Porifera) And Phylum Cnidaria, Karri Michelle Haen

Graduate Theses and Dissertations

Metazoan mitochondrial genomes provide a model system for evolutionary genomic studies. Due to their relatively small size, sequences for complete mitochondrial DNAs (mtDNAs) are now available for animals over a large phylogenetic spectrum, including recent additions for the three classes of Porifera and various cnidarians. This wealth of data gives us a unique opportunity to infer the mechanisms underlying the evolution of genomes. In this dissertation, I will address the example of extensive parallel evolution between two distantly related groups, the Bilateria and Class Hexactinellida (Phylum Porifera; glass sponges), citing the specific examples of degenerated tRNA secondary structures and changes ...


Trophic Implications Of Light Reductions For Amphibolis Griffithii Seagrass Fauna, Adam Gartner 2010 Edith Cowan University

Trophic Implications Of Light Reductions For Amphibolis Griffithii Seagrass Fauna, Adam Gartner

Theses: Doctorates and Masters

The ongoing threat of seagrass loss from reduced light availability, coupled with our lack of knowledge of associated trophic responses has motivated this characterization of the flow-on effects of light reductions to Amphibolis griffithii seagrass fauna. Recently, field manipulations of varying light reductions, induced disturbances in a A. griffithii seagrass meadow that have been shown to effect potential food resources and the structural complexity of seagrass habitats for macroinvertebrates. This offered the opportunity to assess the flow-on effects to seagrass for fauna, a topic that has seldom been examined. This study investigated the effects of different light reduction intensity (high ...


Reproductive Behavior In Horseshoe Crabs: Does Density Matter?, Jennifer Mattei, Mark Beekey, Adam Rudman, Alyssa Woronik 2010 Sacred Heart University

Reproductive Behavior In Horseshoe Crabs: Does Density Matter?, Jennifer Mattei, Mark Beekey, Adam Rudman, Alyssa Woronik

Biology Faculty Publications

While the four species of horseshoe crabs share many common reproductive traits with respect to their reproductive systems, they do differ with respect to their mating behavior (monogamy vs. polygynandry). Past research has attributed these differences to a number of factors including: spawning densities, operational sex ratios (OSR’s), male condition (or age), environmental and/or genetic factors, or a combination thereof. Mating behaviors in the three Asian horseshoe crab species (Tachypleus gigas , T. tridentatus, and Carcinoscorpius rotundicauda ) with low spawning densities and 1:1 operational sex ratios are typically monogamous. In Limulus polyphemus , mating behavior is more variable ranging ...


Early Cranial Patterning In The Direct-Developing Frog Eleutherodactylus Coqui Revealed Through Gene Expression, Ryan Kerney, Joshua Gross, James Hanken 2009 Gettysburg College

Early Cranial Patterning In The Direct-Developing Frog Eleutherodactylus Coqui Revealed Through Gene Expression, Ryan Kerney, Joshua Gross, James Hanken

Ryan Kerney

Genetic and developmental alterations associated with the evolution of amphibian direct development remain largely unexplored. Specifically, little is known of the underlying expression of skeletal regulatory genes, which may reveal early modifications to cranial ontogeny in direct-developing species. We describe expression patterns of three key skeletal regulators (runx2, sox9, and bmp4) along with the cartilage-dominant collagen 2a1 gene (col2a1) during cranial development in the direct- developing anuran, Eleutherodactylus coqui. Expression patterns of these regulators reveal transient skeletogenic anlagen that correspond to larval cartilages, but which never fully form in E. coqui. Suprarostral anlagen in the frontonasal processes are detected through ...


Fitness Variation Due To Sexual Antagonism And Linkage Disequilibrium, Manus Patten, David Haig, Fransisco Úbeda de Torres 2009 University of Tennessee, Knoxville

Fitness Variation Due To Sexual Antagonism And Linkage Disequilibrium, Manus Patten, David Haig, Fransisco Úbeda De Torres

Francisco Úbeda de Torres

Extensive fitness variation for sexually antagonistic characters has been detected in nature. However, current population genetic theory suggests that sexual antagonism is unlikely to play a major role in the maintenance of variation. We present a twolocus model of sexual antagonism that is capable of explaining greater fitness variance at equilibrium than previous single-locus models. The second genetic locus provides additional fitness variance in two complementary ways. First, linked loci can maintain gene variants that are lost in single-locus models of evolution, expanding the opportunity for polymorphism. Second, linkage disequilibrium results between any two sexually antagonistic genes, producing an excess ...


Diagnostic Exercise: Chronic Vomiting In A Dog., Debra Miller 2009 University of Tennessee, Knoxville

Diagnostic Exercise: Chronic Vomiting In A Dog., Debra Miller

Debra L Miller

An approximately one-and-a-half-year-old, neutered male, mixed-breed dog was presented for a chronic history of vomiting. Profuse diarrhea was also noted during examination. An exploratory laparotomy was performed, bone chips were removed from the stomach, and a raised, circular area of gastric mucosa was biopsied. Histologically, there was severe gastric cryptosporidiosis as well as numerous spiral bacteria, consistent with Helicobacter spp. Polymerase chain reaction revealed visible bands for the 18S ribosomal RNA gene for Cryptosporidium spp. The polymerase chain reaction product was sequenced and was found to be most similar to Cryptosporidium muris. Both the gastric location and the species of ...


Amphibian Decline And Mass Mortality: The Value Of Visualizing Ranavirus In Tissue Sections., Debra Miller, Matthew Gray 2009 University of Tennessee, Knoxville

Amphibian Decline And Mass Mortality: The Value Of Visualizing Ranavirus In Tissue Sections., Debra Miller, Matthew Gray

Debra L Miller

No abstract provided.


Epizootic Ulcerative Syndrome Caused By Aphanomyces Invadans In Captive Bullseye Snakehead Channa Marulius Collected From South Florida, Usa., R. Saylor, Debra Miller, M. Vandersea, M. Bevelhimer, P. Schofield, W. Bennett 2009 University of Tennessee, Knoxville

Epizootic Ulcerative Syndrome Caused By Aphanomyces Invadans In Captive Bullseye Snakehead Channa Marulius Collected From South Florida, Usa., R. Saylor, Debra Miller, M. Vandersea, M. Bevelhimer, P. Schofield, W. Bennett

Debra L Miller

Epizootic ulcerative syndrome (EUS) caused by the oomycete Aphanomyces invadans is an invasive, opportunistic disease of both freshwater and estuarine fishes. Originally documented as the cause of mycotic granulomatosis of ornamental fishes in Japan and as the cause of EUS of fishes in southeast Asia and Australia, this pathogen is also present in estuaries and freshwater bodies of the Atlantic and gulf coasts of the USA. We describe a mass mortality event of 343 captive juvenile bullseye snakehead Channa marulius collected from freshwater canals in Miami-Dade County, Florida. Clinical signs appeared within the first 2 d of captivity and included ...


Response To Vaccination With A Commercial Inactivated Rabies Vaccine In A Captive Colony Of Brazilian Free-Tailed Bats (Tadarida Brasiliensis), Amy Turmelle, Louise Allen, Barbara Schmidt-French, Felix Jackson, Thomas Kunz, Charles Rupprecht, Gary McCracken 2009 University of Tennessee, Knoxville

Response To Vaccination With A Commercial Inactivated Rabies Vaccine In A Captive Colony Of Brazilian Free-Tailed Bats (Tadarida Brasiliensis), Amy Turmelle, Louise Allen, Barbara Schmidt-French, Felix Jackson, Thomas Kunz, Charles Rupprecht, Gary Mccracken

Gary F. McCracken

A captive colony of Brazilian free-tailed bats (Tadarida brasiliensis) was vaccinated with a commercial monovalent inactivated rabies virus (RABV) vaccine (RABVAC 1). Baseline rabies virus neutralizing antibodies (VNA) and the response to vaccination were measured in 50 bats. Rabies VNA was detected in the plasma of 64% (27/42) of bats that had been vaccinated 1 yr prior, but only 19% (8/42) had levels considered adequate. Rabies VNA was detected in the plasma of 63% (5/8) of bats with no record of previous vaccination, suggesting natural RABV exposure before captivity. All bats demonstrated a VNA response by 10 ...


Batrachochytrium Dendrobatidis And The Collapse Of Anuran Species Richness And Abundance In The Upper Manu National Park, Southeastern Peru, Edgar Lehr, Allessandro Catenazzi, Lily Rodriguez, Vance Vrendeburg 2009 Illinois Wesleyan University

Batrachochytrium Dendrobatidis And The Collapse Of Anuran Species Richness And Abundance In The Upper Manu National Park, Southeastern Peru, Edgar Lehr, Allessandro Catenazzi, Lily Rodriguez, Vance Vrendeburg

Edgar Lehr

Amphibians are declining worldwide, but these declines have been particularly dramatic in tropical mountains, where high endemism and vulnerability to an introduced fungal pathogen, Batrachochytrium dendrobatidis (Bd), is associated with amphibian extinctions. We surveyed frogs in the Peruvian Andes in montane forests along a steep elevational gradient (1200-3700 m). We used visual encounter surveys to sample stream-dwelling and arboreal species and leaf-litter plots to sample terrestrial-breeding species. We compared species richness and abundance among the wet seasons of 1999, 2008, and 2009. Despite similar sampling effort among years, the number of species (46 in 1999) declined by 47% between 1999 ...


Darwinian Controversies: An Historiographical Recounting, David Depew 2009 University of Iowa

Darwinian Controversies: An Historiographical Recounting, David Depew

David J Depew

This essay reviews key controversies in the history of the Darwinian research tradition: the Wilberforce-Huxley debate in 1860, early twentieth-century debates about the heritability of acquired characteristics and the consistency of Mendelian genetics with natural selection; the 1925 Scopes trial about teaching evolution; tensions about race, culture, and eugenics at the 1959 centenary celebration Darwin’s Origin of Species; adaptationism and its critics in the Sociobiology debate of 1970s and, more recently, Evolutionary Psychology; and current disputes about Intelligent Design. These controversies, I argue, are etched into public memory because they occur at the emotionally charged boundaries between public-political, technical-scientific ...


Gingival Osteogenic Melanoma In Two Dogs., A. Ellis, B. Harmon, Debra Miller, N. Northup, K. Latimer, E. Uhl 2009 University of Tennessee, Knoxville

Gingival Osteogenic Melanoma In Two Dogs., A. Ellis, B. Harmon, Debra Miller, N. Northup, K. Latimer, E. Uhl

Debra L Miller

Osteogenic melanoma is a rare variant of metaplastic malignant melanoma in human medicine and appears to be a similarly rare variant in dogs. Two dogs with oral malignant melanoma with neoplastic bone formation are reported in this study. Both tumors were characterized by malignant melanocytes that transitioned into neoplastic bone at the deep margins of the neoplasm. Immunohistochemical analysis revealed S100- and Melan-A-positive neoplastic cells adjacent to, and occasionally embedded within, an osteoid and chondroblastic matrix. Scattered clusters of neoplastic cells were also positive for osteocalcin. The findings indicate that in dogs, as in humans, neoplastic melanocytes have metaplastic potential ...


Host Immunity To Repeated Rabies Virus Infection In Big Brown Bats, Gary McCracken 2009 University of Tennessee, Knoxville

Host Immunity To Repeated Rabies Virus Infection In Big Brown Bats, Gary Mccracken

Gary F. McCracken

Bats are natural reservoirs for the majority of lyssaviruses globally, and are unique among mammals in having exceptional sociality and longevity. Given these facets, and the recognized status of bats as reservoirs for rabies viruses (RABVs) in the Americas, individual bats may experience repeated exposure to RABV during their lifetime. Nevertheless, little information exists with regard to within-host infection dynamics and the role of immunological memory that may result from abortive RABV infection in bats. In this study, a cohort of big brown bats (Eptesicus fuscus) was infected intramuscularly in the left and right masseter muscles with varying doses [10 ...


Parelaphostrongylus Tenuis-Associated Meningoencephalitis In A Sika Deer (Cervus Nippon), Richard Gerhold Jr., M Keel, K Arnold, D Hotton, R Beckstead 2009 University of Tennessee, Knoxville

Parelaphostrongylus Tenuis-Associated Meningoencephalitis In A Sika Deer (Cervus Nippon), Richard Gerhold Jr., M Keel, K Arnold, D Hotton, R Beckstead

Richard W. Gerhold Jr., DVM, MS, PhD

An adult, female, free-ranging, sika deer (Cervus nippon yakushimae) from Wicomico County, Maryland, USA, was found circling and having no fear of humans. The animal was euthanized and submitted for a postmortem exam. There were no gross lesions and the deer was negative for rabies. Microscopic examination revealed lymphoplasmacytic, neutrophilic, and eosinophilic meningoencephalitis with intralesional adult nematodes, larvae, and eggs consistent with nematodes in the family Protostrongylidae. Parelaphostrongylus tenuis was identified by polymerase chain reaction and DNA sequencing. To our knowledge, this is the first report of P. tenuis-associated encephalitis in a sika deer.


Small-Scale Divergence In Egg Color Along An Elevation Gradient In The Mexican Jay (Aphelocoma Ultramarina): A Condition-Dependent Response?, John McCormack, Elena Berg 2009 Occidental College

Small-Scale Divergence In Egg Color Along An Elevation Gradient In The Mexican Jay (Aphelocoma Ultramarina): A Condition-Dependent Response?, John Mccormack, Elena Berg

John E. McCormack

The functional significance of bird egg color and patterning is a continuing subject of interest and debate. Extreme polymorphism in eggshell appearance is often thought to be maintained by frequency-dependent selection operating within populations. However, variation could also be explained by small-scale differentiation combined with limited migration. Here, we report the existence of extreme variation in egg color in a population of Mexican Jays (Aphelocoma ultramarina) inhabiting a steep elevation and habitat gradient within a single mountain range, the Sierra del Carmen of Coahuila, Mexico. We quantified egg color of 143 eggs from 54 nests throughout the mountain range, using ...


Biological Stoichiometry Of Plant Production: Metabolism, Scaling, And Ecological Response To Global Change, Andrew Kerkhoff, J.J. Elser, W.F. Fagan, B.J. Enquist 2009 Kenyon College

Biological Stoichiometry Of Plant Production: Metabolism, Scaling, And Ecological Response To Global Change, Andrew Kerkhoff, J.J. Elser, W.F. Fagan, B.J. Enquist

Andrew J Kerkhoff

No abstract provided.


Anuran Susceptibilities To Ranaviruses: Role Of Species Identity, Exposure Route, And A Novel Virus Isolate., J. Hoverman, Matthew Gray, Debra Miller 2009 University of Tennessee, Knoxville

Anuran Susceptibilities To Ranaviruses: Role Of Species Identity, Exposure Route, And A Novel Virus Isolate., J. Hoverman, Matthew Gray, Debra Miller

Debra L Miller

Ranaviruses are responsible for widespread amphibian die-offs, particularly with larval anurans. To understand the factors that may be contributing to the emergence of ranaviruses, we conducted 3 experiments that exposed 3 species of larval anurans to either endemic frog virus 3 (FV3) or an FV3-like isolate from a ranaculture facility. Our goals were to (1) determine the susceptibility of each species to each virus, (2) determine whether direct ingestion of virions or exposure to virions in a water bath were similarly lethal routes of transmission, and (3) quantify the effects of exposure duration on disease outcomes. We conducted our research ...


Batrachochytrium Dendrobatidis In The Live Frog Trade Of Telmatobius (Anura: Ceratophryidae) In The Tropical Andes, Edgar Lehr, Alessandro Catenazzi, Vance Vredenburg 2009 Illinois Wesleyan University

Batrachochytrium Dendrobatidis In The Live Frog Trade Of Telmatobius (Anura: Ceratophryidae) In The Tropical Andes, Edgar Lehr, Alessandro Catenazzi, Vance Vredenburg

Edgar Lehr

Species of frogs in the genus Telmatobius are traded and sold for human consumption in the Andes and in coastal cities of Peru and Bolivia. These frogs are harvested from wild populations. We report high prevalence of infection by the pathogenic fungus Batrachochytrium dendrobatidis in live frogs purchased at the main market in Cusco, Peru, from January 2008 to January 2010. We suggest that the transport of native anurans through the live frog trade could facilitate the spread of this fungus among Andean frogs. The tropical Andes are the most important biodiversity hotspot for amphibians. Because many neotropical taxa are ...


A New Andean Species Of The Hypsiboas Pulchellus Group: Adults, Calls, And Phylogenetic Relationships, Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer 2009 Illinois Wesleyan University

A New Andean Species Of The Hypsiboas Pulchellus Group: Adults, Calls, And Phylogenetic Relationships, Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer

Edgar Lehr

We describe a new species of the Hypsiboas pulchellus Group from the eastern Andes of central Peru (Region Pasco). Calls of both H. melanopleura and the new species are described. The new species is more similar to H. melanopleura and H. palaestes but differs in morphological characters and in coloration pattern. The new species and H. melanopleura are included in a molecular phylogenetic analysis of the H. pulchellus Group that shows them to be sister species and forming a second, independent, Andean clade within the group. New collecting sites for H. melanopleura are provided with the first record in the ...


Darwinian Controversies: An Historiographical Recounting, David Depew 2009 University of Iowa

Darwinian Controversies: An Historiographical Recounting, David Depew

David J Depew

This essay reviews key controversies in the history of the Darwinian research tradition: the Wilberforce-Huxley debate in 1860, early twentieth-century debates about the heritability of acquired characteristics and the consistency of Mendelian genetics with natural selection; the 1925 Scopes trial about teaching evolution; tensions about race, culture, and eugenics at the 1959 centenary celebration Darwin’s Origin of Species; adaptationism and its critics in the Sociobiology debate of 1970s and, more recently, Evolutionary Psychology; and current disputes about Intelligent Design. These controversies, I argue, are etched into public memory because they occur at the emotionally charged boundaries between public-political, technical-scientific ...


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