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Review Of Grosphus Simon, 1880, With Description Of Teruelius Gen. N., A New Buthid Genus From Madagascar (Scorpiones: Buthidae), Graeme Lowe, František Kovařík 2019 Marshall University

Review Of Grosphus Simon, 1880, With Description Of Teruelius Gen. N., A New Buthid Genus From Madagascar (Scorpiones: Buthidae), Graeme Lowe, František Kovařík

Euscorpius

We review the taxonomy of the Madagascar endemic buthid genus Grosphus Simon, 1880. We split the genus and describe Teruelius gen. n. on the basis of nine morphological characters, six of them new for Grosphus: positions of trichobothria d2 on pedipalp femur and Eb3 on chela manus, number of pectine teeth, shape of female basal pectinal tooth, form of hemispermatophore capsule posterior lobe, spiracle shape, metasoma I ventromedian carination, telotarsal setation and UV fluorescence. We discuss functional and taxonomic aspects of these characters, and propose that Teruelius gen. n. is monophyletic, while Grosphus (sensu stricto) is paraphyletic. …


Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xx. Barbaracurus Feti Sp. N. From Somaliland (Buthidae), František Kovařík, Graeme Lowe, František Šťáhlavský, Ali Abdi Hurre 2019 Marshall University

Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xx. Barbaracurus Feti Sp. N. From Somaliland (Buthidae), František Kovařík, Graeme Lowe, František Šťáhlavský, Ali Abdi Hurre

Euscorpius

Barbaracurus feti sp. n. from Somaliland is described and compared with other species of the genus. Additional information is provided on the taxonomy and distribution of the genus Barbaracurus, fully complemented with color photos of specimens of both sexes of the new species, as well as of their habitat. In addition to morphology and hemispermatophores, we also describe the karyotypes of B. feti sp. n. (2n=23). Included is a key for Barbaracurus. Babycurus borellii Rossi, 2019 is synonymized with Barbaracurus yemenensis Kovařík et al., 2018 syn. n. as a junior synonym because the description dated in February 2018 …


Anti-Crispr Vs. Crispr: The Evolutionary Arms Race Between Microorganisms, Rachael M. St. Jacques 2019 James Madison University

Anti-Crispr Vs. Crispr: The Evolutionary Arms Race Between Microorganisms, Rachael M. St. Jacques

Masters Theses, 2010-2019

CRISPR arrays are a defense mechanism employed by bacteria against viral invaders. Cas proteins do the work in detecting, capturing, and integrating the viral DNA into the CRISPR array (Barrangou et al., 2007). Anti-CRISPR proteins are produced by phages, viruses that infect bacteria, to stop the bacterial host’s CRISPR-Cas complex from interrupting the phage life cycle (Bondy-Denomy, et al., 2015).

SEA-PHAGES is a course-based bacteriophage research network composed of 120 colleges and known at James Madison University as Viral Discovery. JMU uses the unsequenced Streptomyces griseus ATCC10137 as a host for bacteriophage discovery and propagation, and in this study we …


Phylogenomics And Geometric Morphometrics Define Species Flocks Of Snowtrout (Teleostei: Schizothorax) In The Central Himalayas, Binod Regmi 2019 University of Arkansas, Fayetteville

Phylogenomics And Geometric Morphometrics Define Species Flocks Of Snowtrout (Teleostei: Schizothorax) In The Central Himalayas, Binod Regmi

Graduate Theses and Dissertations

Schizothorax (Snowtrout) is a genus of medium-sized minnows (Cypriniformes) inhabiting glacier-fed streams, rivers, and lakes in the Himalayas. There are more than 30 species of Schizothorax across the region. The speciation and diversity of the Snowtrout in the vast hinterlands of the Himalayan Region has not been fully explored. Three species in Lake Rara, Western Nepal are considered a species flock, comprising endemic ecotypes that are morphologically differentiated and reproductively isolated.

My dissertation research examined the diversity of Schizothorax in the Central Himalayan region and evolutionary relationships among species distributed in the Tibet, Central and Southeast Asia. Chapter I describes …


The Functional Morphology Of Ingestion In The Platyrrhine Sclerocarpic Harvesters (Platyrrhini, Primates), Zachary Stoffel Klukkert 2019 CUNY Graduate Center

The Functional Morphology Of Ingestion In The Platyrrhine Sclerocarpic Harvesters (Platyrrhini, Primates), Zachary Stoffel Klukkert

Dissertations, Theses, and Capstone Projects

The identification of anatomical correlates of diet and feeding behavior in nonhuman primates is an important area of research in biological anthropology. The morphology of the jaws and teeth reflects the phylogeny and adaptations that distinguish taxa and their different ecological niches. Studying the form-function relationships of jaws and teeth in modern species provides a framework for interpreting the diets of extinct species and for inferring the ecological pressures that may have contributed to the evolutionary diversification of primate craniodental morphology. Previous work on modeling primate jaw mechanics has focused largely on the functional context of a closed jaw. Little …


Ecometric Estimation Of Present And Past Climate Of North America Using Crown Heights Of Rodents And Lagomorphs: With Application To The Middle Miocene Climatic Optimum, Julia Schap 2019 East Tennessee State University

Ecometric Estimation Of Present And Past Climate Of North America Using Crown Heights Of Rodents And Lagomorphs: With Application To The Middle Miocene Climatic Optimum, Julia Schap

Electronic Theses and Dissertations

Continental scale studies on ungulate crown heights in relation to climate and habitat changes have revealed a correlation between increasing hypsodonty and a shift to more arid environments. Small mammals have been shown to adapt to changing habitats millions of years earlier than larger mammals. In this study I examined fossil localities throughout the last 37 Ma across North America. Diversity of rodents and lagomorphs were analyzed through this time period, with examination of community structure characterized by relative percentages of taxa with different crown heights. Overall, a decrease in precipitation and temperature was found across North America from 37 …


Differentiating Black Bears (Ursus Americanus) And Brown Bears (U. Arctos) Using Linear Tooth Measurements And Identification Of Ursids From Oregon Caves National Monument, Emily Bogner 2019 East Tennessee State University

Differentiating Black Bears (Ursus Americanus) And Brown Bears (U. Arctos) Using Linear Tooth Measurements And Identification Of Ursids From Oregon Caves National Monument, Emily Bogner

Electronic Theses and Dissertations

North American black bears and brown bears can be difficult to distinguish in the fossil record due to similar dental and skeletal morphologies. Challenges identifying ursid material from Oregon Caves National Monument (ORCA) called for an accurate tool to distinguish the species. This study utilized a large database of lower tooth lengths and ratios in an attempt to differentiate black and brown bears in North America. Further, this project examined how these linear measurements differ geographically. Analysis of variance (ANOVA) found significant differences between black and brown bears from across North America for every variable studied. Stepwise discriminant analyses (DA) …


The Role Of Gene Expression Noise In Mammalian Cell Survival, Kevin Farquhar 2019 The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences

The Role Of Gene Expression Noise In Mammalian Cell Survival, Kevin Farquhar

Dissertations and Theses (Open Access)

Drug resistance and metastasis remain obstacles to effective cancer treatment. A major challenge contributing to this problem is cellular heterogeneity. Even in the same environment, cells with identical genomes can display cell-to-cell differences in gene expression, also known as gene expression noise. Gene expression noise can vary in magnitude in a population or in fluctuation time scales, which is influenced by gene regulatory networks.

Currently, it is unclear how gene expression noise from gene regulatory networks contributes to drug survival outcomes in mammalian cells. An isogenic cell line with a noise-modulating genetic system tuned to the same mean is required. …


Characterization Of Microtubule Organizing Centers In The Genus Protostelium, Including Evolutionary Implications, Ethan Taylor Ozment 2019 University of Arkansas, Fayetteville

Characterization Of Microtubule Organizing Centers In The Genus Protostelium, Including Evolutionary Implications, Ethan Taylor Ozment

Graduate Theses and Dissertations

Microtubule organizing centers (MTOCs) are cellular regions of microtubule nucleation. The best known MTOCs are those associated with the centrosome, but several non-centrosomal MTOCs are known in eukaryotes, especially in land plants. MTOCs are poorly characterized across the breadth of amoebozoan diversity, but are well-known in certain amoebozoan lineages, including the genus of protosteloid slime molds Protostelium. The structure of the MTOC is known for two non-ciliated species, P. nocturnum and P. mycophaga, as well as P. aurantium, which can reversibly become ciliated under appropriate conditions. P. nocturnum and P. mycophaga have acentriolar centrosomal MTOCs while P. aurantium has a …


Phylogeny Of The Australian Solanum Dioicum Group Using Seven Nuclear Genes: Testing Symon’S Fruit And Seed Dispersal Hypotheses., Christopher T. Martine, Ingrid E. Jordon-Thaden, Angela J. McDonnell, Jason T. Cantley, Daniel S. Hayes, Morgan D. Roche, Emma S. Frawley, Ian S. Gilman, David C. Tank 2019 Bucknell University

Phylogeny Of The Australian Solanum Dioicum Group Using Seven Nuclear Genes: Testing Symon’S Fruit And Seed Dispersal Hypotheses., Christopher T. Martine, Ingrid E. Jordon-Thaden, Angela J. Mcdonnell, Jason T. Cantley, Daniel S. Hayes, Morgan D. Roche, Emma S. Frawley, Ian S. Gilman, David C. Tank

Faculty Journal Articles

The dioecious and andromonoecious Solanum taxa (the “S. dioicum group”) of the Australian Monsoon Tropics have been the subject of phylogenetic and taxonomic study for decades, yet much of their basic biology is still unknown. This is especially true for plant-animal interactions, including the influence of fruit form and calyx morphology on seed dispersal. We combine field/greenhouse observations and specimen-based study with phylogenetic analysis of seven nuclear regions obtained via a microfluidic PCR-based enrichment strategy and high-throughput sequencing, and present the first species-tree hypothesis for the S. dioicum group. Our results suggest that epizoochorous trample burr seed …


Evolution Of Endurance Running Genes Across Primates, Natalia T. Grube 2019 CUNY Hunter College

Evolution Of Endurance Running Genes Across Primates, Natalia T. Grube

Theses and Dissertations

The endurance running hypothesis has emerged as a key idea to explain several unique anatomical, physiological, and genetic features of modern humans—among these features is the evolution of ACTN3 (Bramble & Lieberman 2004, Nature), a gene linked to human athletic performance. An additional gene linked to human endurance performance is ACE. Because endurance running is a uniquely human trait, I predicted that ACE and ACTN3 genes would be evolving adaptively in the human lineage when examined in a wider primatological framework. To test this I compiled ACE and ACTN3 genes from 14 primate species and phylogenetically tested if these genes …


Co-Occurrence Of Manganese Oxidase Genes Indicates Lateral Transfer Between Classes Of Proteobacteria, Jacob Olichney 2019 University of Lynchburg

Co-Occurrence Of Manganese Oxidase Genes Indicates Lateral Transfer Between Classes Of Proteobacteria, Jacob Olichney

Student Scholar Showcase

Pseudomonas putida GB-1 is a model organism for the study of manganese oxidation in bacteria, however, the frequency of co-localization of multiple known and suspected manganese oxidizing proteins, as well as their occurrence between species, is unknown. Eight different genes isolated from known manganese oxidizing bacteria (MnxG, MopA, McoA, PputGB1_2552, PputGB1_2553, MoxA, MofA, and Bacillus MnxG) were tested individually using BioPython and BLAST (Basic Local Alignment Search Tool) on multiple genomic databases. BLAST searches had an expect value cutoff of 1e-50, limiting gene homologs to those with high sequence similarity. The abundance of homologous genes across classes of proteobacteria point …


Comparing Feeding Accuracy Between High And Low Predation Trinidad Guppies, Lydia J. Bonnell 2019 Georgia Southern University

Comparing Feeding Accuracy Between High And Low Predation Trinidad Guppies, Lydia J. Bonnell

Honors College Theses

Efficient feeding accuracy could increase an organism’s survival. Although local adaptation in Trinidad guppies is common, the effects on accuracy are unknown. Guppies were wild caught in 2015 and 2017, filmed while capturing prey. Accuracy wasn’t different within samples but differed across samples, possibly due to the prey types used.


Documenting Evolution: Comparing And Contrasting Late Mesozoic And Late Cenozoic Molluscan Patterns, Joshua Slattery 2019 University of South Florida

Documenting Evolution: Comparing And Contrasting Late Mesozoic And Late Cenozoic Molluscan Patterns, Joshua Slattery

USF Tampa Graduate Theses and Dissertations

Despite major advances, evolutionary theory still has numerous shortcomings in terms of fully understanding the controls on speciation and diversification. A major factor limiting our knowledge is how biology and paleobiology view speciation from separate micro- and macro-evolutionary perspectives, respectively. Biologists typically examine microevolutionary changes within species from various biogeographic, behavioral, morphological, and genetic perspectives, which contrasts to the macroevolutionary approach of most paleobiologists, who have examined the same phenomena at larger scales but with the standpoint of time, have also concentrated on aspects of global or regional diversification (e.g., richness, origination rates, and extinction rates) over the long-term. Noticeably …


A Phylogenetic Analysis Of Bostrichoidea (Coleoptera) And Revisions Of The Southern African Spider Beetle Genera Meziomorphum And Eutaphroptinus (Ptinidae: Coleoptera), Olivia M. Gearner 2019 Western Kentucky University

A Phylogenetic Analysis Of Bostrichoidea (Coleoptera) And Revisions Of The Southern African Spider Beetle Genera Meziomorphum And Eutaphroptinus (Ptinidae: Coleoptera), Olivia M. Gearner

Masters Theses & Specialist Projects

Proposals for the internal relationships and classification of the bostrichoids are currently poorly supported, and almost all are based on morphology alone. This study improves upon on previous phylogenetic analyses of the group by including more taxa using the standard genes for many phylogenetic analyses. Cytochrome C oxidase subunit 1 (CO1), 28S small subunit rRNA, and 16S small subunit rRNA mitochondrial genes were sequenced or obtained from Genbank, then analyzed using parsimony and Bayesian analyses. Topologies differed depending on genes used. A three gene tree and a two gene (28S and CO1) tree both supported relationships in which a basal …


Plant Mitochondrial Genome Evolution And Structure Has Been Shaped By Double-Strand Break Repair And Recombination, Emily Wynn 2019 University of Nebraska-Lincoln

Plant Mitochondrial Genome Evolution And Structure Has Been Shaped By Double-Strand Break Repair And Recombination, Emily Wynn

School of Biological Sciences: Dissertations, Theses, and Student Research

Plant mitochondrial genomes are large but contain a small number of genes. These genes have very low mutation rates, but genomes rearrange and expand at significant rates. We propose that much of the apparent complexity of plant mitochondrial genomes can be explained by the interactions of double-strand break repair, recombination, and selection. One possible explanation for the disparity between the low mutation rates of genes and the high divergence of non-genes is that synonymous mutations in genes are not truly neutral. In some species, rps14 has been duplicated in the nucleus, allowing the mitochondrial copy to become a pseudogene. By …


Arterial Distribution Of The Human Aorta: An Examination Of The Evolutionary, Developmental, And Physiological Bases Of Asymmetry., Brandon Oddo, Cooker Storm 2019 Pepperdine University

Arterial Distribution Of The Human Aorta: An Examination Of The Evolutionary, Developmental, And Physiological Bases Of Asymmetry., Brandon Oddo, Cooker Storm

Seaver College Research And Scholarly Achievement Symposium

The study of anatomy contends that “form follows function”; a disciplinary theme purporting that anatomical structures (i.e., cells, tissues, and organs) have a shape that serves its proper function. With this in mind, it is unclear why human arterial distribution off the aortic arch is asymmetrical, while the corresponding venous anatomy is symmetrical. We investigated the evolutionary, developmental, and physiological bases for the asymmetry of aortic arch branches in humans. First, we investigated the cardiovascular anatomy of ancestral species to determine if, and at what level, anatomical divergence (from aortic symmetry to asymmetry) occurs. Second, we examined the formation of …


Genomics Based Approaches To Fungal Evolution, Aaron J. Robinson, Donald O. Natvig 2019 University of New Mexico

Genomics Based Approaches To Fungal Evolution, Aaron J. Robinson, Donald O. Natvig

Biology ETDs

Advances in DNA sequencing and data analysis make it possible to address questions in population genetics and evolution at the genomic level. Fungi are excellent subjects for such studies, because they are found in diverse environments, have short generation times, can be maintained in culture and have relatively small genomes. My research employed genetic approaches using a variety of sequencing technologies and methods of analysis to explore questions in fungal evolution.

In one study, I explored the genetics behind differences in thermotolerance between isolates of Neurospora discreta from Alaska and New Mexico. Isolates from the two states exhibited differences in …


Area And Distance From Mainland Affect In Different Ways Richness And Phylogenetic Diversity Of Snakes In Atlantic Forest Coastal Islands, José Thales da Motta Portillo, Lilian Sayuri Ouchi-Melo, Lucas Batista Crivellari, Thiago Alves Lopes de Oliveira, Ricardo J. Sawaya, Leonardo da Silva Duarte 2019 Universidade Estadual Paulista “Júlio de Mesquita Filho”

Area And Distance From Mainland Affect In Different Ways Richness And Phylogenetic Diversity Of Snakes In Atlantic Forest Coastal Islands, José Thales Da Motta Portillo, Lilian Sayuri Ouchi-Melo, Lucas Batista Crivellari, Thiago Alves Lopes De Oliveira, Ricardo J. Sawaya, Leonardo Da Silva Duarte

Publications and Research

Aim: The Theory of Island Biogeography posits that ecological and evolutionary processes regulate species richness of isolated areas. We assessed the influences of an island area and distance from the mainland on species richness, phylogenetic diversity, and phylogenetic composition of snakes on coastal islands.

Location: Coastal islands of the megadiverse Atlantic Forest in southeastern Brazil.

Methods: We compiled the species composition of 17 coastal islands in southeastern Brazil. Species richness and phylogenetic diversity were calculated for each island. Phylogenetic composition was measured using principal coordinates of phylogenetic structure. We then employed generalized linear models to test the influence of …


Phylogeny And Evolution Of Swallows (Hirundinidae) With A Transcriptomic Perspective On Seasonal Migration, Clare Elisabeth Brown 2019 Louisiana State University and Agricultural and Mechanical College

Phylogeny And Evolution Of Swallows (Hirundinidae) With A Transcriptomic Perspective On Seasonal Migration, Clare Elisabeth Brown

LSU Doctoral Dissertations

Evolutionary biology seeks to understand the forces that have generated and shaped patterns of diversity. In this dissertation, I investigated phylogenetic relationships and the evolution of three traits—migration, nest-type, and geographic distribution—in the swallow family (Hirundinidae), a globally distributed group of about 85 species of aerial insectivorous birds. I first applied a dataset of several thousand ultraconserved element (UCE) loci to reconstructing the phylogeny of the New World genus Tachycineta. Three methods of phylogenetic inference produced topologically discordant trees, but post-inference analyses provided evidence that the tree produced by maximum likelihood analysis of a concatenated data matrix is the most …


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