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2021

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Full-Text Articles in Evolution

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxvii. Lanzatus Huluul Sp. N. From Somaliland (Buthidae), František Kovařík, Graeme Lowe Dec 2021

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxvii. Lanzatus Huluul Sp. N. From Somaliland (Buthidae), František Kovařík, Graeme Lowe

Euscorpius

The rare Horn of Africa buthid genus Lanzatus Kovařík, 2001 was newly collected in Somaliland in two localities. We describe a new species Lanzatus huluul sp. n. fully illustrated with color photos showing its morphology, habitus, hemispermatophore and collection areas.


The Energetics Of Uniquely Human Subsistence Strategies, Thomas S. Kraft, Vivek V. Venkataraman, Ian J. Wallace, Alyssa N. Crittenden, Nicholas B. Holowka, Jonathan Stieglitz, Jacob Harris, David A. Raichlen, Brian Wood, Michael Gurven, Herman Pontzer Dec 2021

The Energetics Of Uniquely Human Subsistence Strategies, Thomas S. Kraft, Vivek V. Venkataraman, Ian J. Wallace, Alyssa N. Crittenden, Nicholas B. Holowka, Jonathan Stieglitz, Jacob Harris, David A. Raichlen, Brian Wood, Michael Gurven, Herman Pontzer

Anthropology Faculty Research

The suite of derived human traits, including enlarged brains, elevated fertility rates, and long developmental periods and life spans, imposes extraordinarily high energetic costs relative to other great apes. How do human subsistence strategies accommodate our expanded energy budgets? We found that relative to other great apes, human hunter-gatherers and subsistence farmers spend more energy but less time on subsistence, acquire substantially more energy per hour, and achieve similar energy efficiencies. These findings revise our understanding of human energetic evolution by indicating that humans afford expanded energy budgets primarily by increasing rates of energy acquisition, not through energy-saving adaptations such …


A New Species Of Vaejovis From The Mule Mountains Above Bisbee, Arizona (Scorpiones: Vaejovidae), Brandon T. Myers, Richard F. Ayrey Dec 2021

A New Species Of Vaejovis From The Mule Mountains Above Bisbee, Arizona (Scorpiones: Vaejovidae), Brandon T. Myers, Richard F. Ayrey

Euscorpius

No abstract provided.


Co-Option Of The Yolkless Oocyte Receptor For Crispr/Cas9 May Induce Transient Sterility In Female Drosophila Grimshawi Flies, Bronwyn Miller Dec 2021

Co-Option Of The Yolkless Oocyte Receptor For Crispr/Cas9 May Induce Transient Sterility In Female Drosophila Grimshawi Flies, Bronwyn Miller

LSU New Orleans Theses and Dissertations

Evolutionary developmental biology has historically used generalist model organisms like Drosophila melanogaster. The Hawaiian Drosophilidae radiation, which occurred just 25 million years ago, is an ideal lineage for work in Evo-Devo. Hawaiian flies make up 25% of the world’s Drosophila species and extreme diversity is seen throughout the group. D. grimshawi is a generalist Hawaiian picture-wing fly that has served as a model for the Hawaiian Drosophilidae radiation. However, D. grimshawi’s power and use as a model organism is constrained by our lack of ability to manipulate its genome. In this work, I attempted to edit the genome of …


Lipidomic Analysis Of Various Developmental Stages Of Physcomitrium Patens, Deepshila Gautam Dec 2021

Lipidomic Analysis Of Various Developmental Stages Of Physcomitrium Patens, Deepshila Gautam

Electronic Theses and Dissertations

Lipids maintain fluidity of the cell membrane during the lifetime of all organisms. The moss Physcomitrium patens, an early land plant, enters reproductive phase under cold (15°C) conditions relative to its gametophytes (22°C). Thus, we hypothesized that their lipid content and composition would be distinct. Using ESI-MS/MS, we showed that the content and acyl composition of 11 lipid classes varied during development. Galactolipids were abundant in gametophytes but insignificant in sporophytes; among phospholipids, phosphatidylcholine was predominant in both phases. Although, sporophytes contained around five-fold less lipids than the gametophyte, their phosphatidic acid content, which accumulates during stress, was 18-fold …


Amphibians And Reptiles As Prey Of Heteroctenus Junceus (Scorpiones: Buthidae), With A Summary Of Vertebrate Predation By Scorpions In The West Indies, Tomás M. Rodríguez-Cabrera,, Ernesto Morell Savall, Rolando Teruel Nov 2021

Amphibians And Reptiles As Prey Of Heteroctenus Junceus (Scorpiones: Buthidae), With A Summary Of Vertebrate Predation By Scorpions In The West Indies, Tomás M. Rodríguez-Cabrera,, Ernesto Morell Savall, Rolando Teruel

Euscorpius

Vertebrate predation by scorpions has been scarcely documented in the literature. Contrary to large scorpions of the genera Centruroides, Hadrurus, Opistophthalmus, and Pandinurus from North America and Africa, which are capable of subduing even small rodents and bats, West Indian scorpions of the genera Centruroides, Heteroctenus, and Tityus seem to limit their prey to amphibians and reptiles. Herein we present new cases of a frog (Osteopilus septentrionalis; Hylidae) and three lizards (Anolis allisoni, A. ophiolepis, and A. sagrei; Dactyloidae) preyed upon by Heteroctenus junceus (Herbst, 1800), at the time we summarize all cases of vertebrate …


The Evolutionary Origins Of Autism Associated Genes And Their Role In Great Ape Socio-Communicative Behavior, Azeeza Abdulrauf Nov 2021

The Evolutionary Origins Of Autism Associated Genes And Their Role In Great Ape Socio-Communicative Behavior, Azeeza Abdulrauf

Master of Science in Integrative Biology Theses

Autism Spectrum Disorder (ASD) is a set of neurological disorders characterized by reduced social interactions and deficits in verbal and nonverbal communication. Although there are no clear genetic markers for ASD, studies have found associations between gene single nucleotide polymorphisms (SNPs) and patients diagnosed with ASD. For this study, the focus is on OXTR, AVPR1A, and FOXP2. OXTR is reported to regulate empathy and stress reactivity while AVPR1A is reported to regulate stress management and territorial aggression, as well as social bonding and recognition. FOXP2 is one of the first genes to be associated with both speech and language recognition …


Androctonus Turkiyensis Sp. N. From The Şanlıurfa Province, Turkey (Scorpiones: Buthidae), Ersen A. Yağmur Nov 2021

Androctonus Turkiyensis Sp. N. From The Şanlıurfa Province, Turkey (Scorpiones: Buthidae), Ersen A. Yağmur

Euscorpius

A new species Androctonus turkiyensis sp. n. is described and illustrated from the Şanlıurfa Province of Turkey. The new species is compared with A. crassicauda (Olivier, 1807), which was previously misidentified from Turkey. A. crassicauda specimens used for comparison were collected from Kashan County (Iran), the type locality of this species; a neotype from Kashan is designated.


The First Troglobitic Scorpions From Hispaniola, Greater Antilles: Two New Species Of Cazierius Francke, 1978 (Scorpiones: Diplocentridae), Rolando Teruel, Solanlly Carrero Jiménez, Gabriel De Los Santos Nov 2021

The First Troglobitic Scorpions From Hispaniola, Greater Antilles: Two New Species Of Cazierius Francke, 1978 (Scorpiones: Diplocentridae), Rolando Teruel, Solanlly Carrero Jiménez, Gabriel De Los Santos

Euscorpius

Two new species of the Greater Antillean endemic scorpion genus Cazierius Francke, 1978, are herein described from the island of Hispaniola. They were found inside isolate limestone caves in the Dominican Republic and are fully troglomorphic, thus, apparently being strict troglobites that represent the first ever documented for this genus. The present additions raise the number of Hispaniolan species of both Cazierius and the family Diplocentridae Karsch, 1880, to five and ten, respectively.


Comparative Phylogeography Across Multiple Scales: Small Mammals, Their Ecology, Pathogens, And Drivers Of Diversification, Schuyler W. Liphardt Nov 2021

Comparative Phylogeography Across Multiple Scales: Small Mammals, Their Ecology, Pathogens, And Drivers Of Diversification, Schuyler W. Liphardt

Biology ETDs

Comparative phylogeography has historically been defined as the study of how genetic variation of co-distributed species has been shaped by biogeographical history. This is a mature field of study out of which several techniques have been developed directed at identifying the role ecology and geography in diversification patterns across time. I employ the tools developed in classical comparative phylogeography across multiple taxonomic scales and across regions that historically have been understudied. My first two chapters study the complex history of host-switching, codiversification, and reassortment of hantaviruses in their mammal hosts across North America. By taking a host-centric comparative phylogeographic approach …


Resource Allocation And Phenotypic Plasticity Of Simultaneous Hermaphroditic Turtle Barnacles (Chelonibia Testudinaria), Kevin C. Cash Nov 2021

Resource Allocation And Phenotypic Plasticity Of Simultaneous Hermaphroditic Turtle Barnacles (Chelonibia Testudinaria), Kevin C. Cash

All HCAS Student Capstones, Theses, and Dissertations

This research addresses the knowledge gap of phenotypic plasticity in a commonly found and important species of epizoic barnacle, Chelonibia testudinaria. Limited research has been published regarding how phenotypic expression is mediated the spatial distribution of barnacles on a mobile host. To investigate this potential relationship, barnacles were collected from the backs of turtles along the beaches of Fort Lauderdale Florida. These barnacles were assessed for various phenotypic traits as well as their corresponding spatial distribution on the turtle carapace. Barnacles were safely removed from the carapace using a chisel before their preservation in ethanol. Barnacles were then numbered …


The Correct Identity Of Centruroides Hoffmanni Armas, 1996 (Scorpiones: Buthidae), With The Description Of A New Species From Chiapas, Mexico, Luis De Armas, Rolando Teruel Nov 2021

The Correct Identity Of Centruroides Hoffmanni Armas, 1996 (Scorpiones: Buthidae), With The Description Of A New Species From Chiapas, Mexico, Luis De Armas, Rolando Teruel

Euscorpius

The Mexican scorpion Centruroides hoffmanni Armas, 1996 was described on the basis of a supposed adult female (actually a juvenile) from La Gloria, Arriaga Municipality, southwest of the Chiapas State. In its redescription, this species was also recorded from the southeastern of Oaxaca State. Nevertheless, in the recent revision of the “thorellii” species-group of the genus Centruroides Marx, 1890, a new species from Chiapas was misidentified as C. hoffmanni and, also, an erroneous new diagnosis was given for C. hoffmanni. In the present contribution, this new species is named Centruroides concordia sp. n., and the correct identity of C. …


Ubiquitous Yet Inconspicuous: Quantifying Trophic Impact Of A Widespread Oceanic Comb Jelly (Ctenophore), Elizabeth Potter Nov 2021

Ubiquitous Yet Inconspicuous: Quantifying Trophic Impact Of A Widespread Oceanic Comb Jelly (Ctenophore), Elizabeth Potter

USF Tampa Graduate Theses and Dissertations

The oceanic lobate ctenophore Ocyropsis spp. has a widespread distribution throughout the world’s tropical and sub-tropical oceans. While patchy, Ocyropsis spp. population densities are known to exceed one individual per m3. Studies of coastal ctenophores have shown that some species are capable of exerting strong predatory impacts on their ecosystems, but little is known about the potential trophic impacts of their oceanic relatives. Many oceanic genera such as Ocyropsis, Bolinopsis, and Eurhamphaea exhibit morphologies and prey capture mechanisms that are different from the more well-studied coastal species. Thus, existing data on coastal taxa may not apply to oceanic species due …


Ecological Genomics Of Two Coastal Foundation Plant Species, Jeannie Mounger Nov 2021

Ecological Genomics Of Two Coastal Foundation Plant Species, Jeannie Mounger

USF Tampa Graduate Theses and Dissertations

I was born and raised in rural Florida on a tributary of the Withlacoochee River. “Withlacoochee” comes from a series of Muscogee Creek words that together mean “big little water,” possibly owing to the seasonal fluctuations in the breadth and flow of the river or to the chain of lakes that in part form it. The name contains within it an understanding of the capacity of land and water to undergo great shifts. It conjures images of mutable boundaries, of water covering and receding across the landscape over and over again. Many of my clearest memories from childhood are related …


Genetic Structuring And Community Assembly In Neotropical Birds, Oscar Johnson Nov 2021

Genetic Structuring And Community Assembly In Neotropical Birds, Oscar Johnson

LSU Doctoral Dissertations

The factors that influence how species form is of fundamental interest to biology. Under the framework of the speciation cycle, the process begins by population subdivision creating structured populations that then diverge until two new species form. Following speciation, however, continued divergence is necessary for these new species to be able to coexist without adverse interactions, known as the transition to secondary sympatry. At this point the speciation cycle is complete and the process can begin anew. Many of the factors influencing these processes remain poorly understood. Here, I explore the factors that influence speciation and community assembly in Neotropical …


Evolutionary Mechanisms For Host Resistance To Tumor Growth And Subsequent Cancer Cell Counter-Adaptations, Arig Ibrahim Hashim Nov 2021

Evolutionary Mechanisms For Host Resistance To Tumor Growth And Subsequent Cancer Cell Counter-Adaptations, Arig Ibrahim Hashim

USF Tampa Graduate Theses and Dissertations

Cancer is well-recognized as an evolutionary system, as first proposed by Cairns and Nowell more than 60 years ago. In an evolutionary context, cancers growing in vivo typically consist of heterogeneous subpopulations of cells that interact with each other and with host cells through selection forces operating at many temporal and spatial scales. Moreover, the tumor environment comprises more than just cancer cells; it includes a rich cancer stroma and cancer-driving molecules such as cytokines and metabolites. The tumor’s environment comprises intratumoral heterogeneity that often leads to therapy resistance attributed to the essential roles of many genetic and nongenetic mechanisms. …


The Role Of Zingiberales Shared Evolutionary History And Leaf Traits In Structuring Rolled-Leaf Beetle Assemblages In A Tropical Forest, José Miguel Chaves Fallas Nov 2021

The Role Of Zingiberales Shared Evolutionary History And Leaf Traits In Structuring Rolled-Leaf Beetle Assemblages In A Tropical Forest, José Miguel Chaves Fallas

Dissertations

Understanding how local assemblages of plants and animals are structured is a central challenge for evolutionary ecology. Tropical assemblages are high in species numbers and in variety of ecological interactions, providing unique multispecies biological systems to test ecological and evolutionary hypotheses about community assembly. The objective of this dissertation was to understand the role of Zingiberales shared evolutionary history and plant traits for structuring the rolled-leaf beetle (Cephaloleia and Chelobasis, Chrysomelidae) assemblage in a lowland wet forest (La Selva Biological Station) of Costa Rica.

In chapter I studied the evolution of physical, nutritional, and chemical leaf traits, how …


Historical Dna Solves An Evolutionary Mystery And Explains The Origin Of A Novel Phenotype In The New World Quails, Jessie Frances Salter Oct 2021

Historical Dna Solves An Evolutionary Mystery And Explains The Origin Of A Novel Phenotype In The New World Quails, Jessie Frances Salter

LSU Doctoral Dissertations

Observations of phenotypic diversity among closely-related organisms, especially those preserved as museum specimens, have driven the fields of systematics, taxonomy, and evolutionary biology for hundreds of years. In this dissertation, I used genomic data from modern and historical specimens to investigate the evolutionary processes that have generated phenotypic and genetic diversity in a highly polytypic group of birds, the New World quails (Odontophoridae), with a focus on the most phenotypically diverse member of this family: Northern Bobwhites (Colinus virginianus). To facilitate this work, I began by generating a highly contiguous reference genome assembly for Northern Bobwhites, which is …


A New Species Of Pseudouroctonus From The Pinaleño Mountains, Southern Arizona (Scorpiones: Vaejovidae), Richard F. Ayrey, František Kovařík, Brandon T. Myers Sep 2021

A New Species Of Pseudouroctonus From The Pinaleño Mountains, Southern Arizona (Scorpiones: Vaejovidae), Richard F. Ayrey, František Kovařík, Brandon T. Myers

Euscorpius

A new scorpion species, Pseudouroctonus moyeri sp. n. (Scorpiones: Vaejovidae) is described. This large, dark, reddish brown species is found in the Pinaleño Mountains, Arizona. This is the largest species of Pseudouroctonus found in Arizona. Ruberhieronymus Rossi, 2018 is synonymized with Pseudouroctonus Stahnke, 1974


Mitonuclear Mismatch Is Associated With Increased Male Frequency, Outcrossing, And Male Sperm Size In Experimentally-Evolved C. Elegans, Brent William Bever Sep 2021

Mitonuclear Mismatch Is Associated With Increased Male Frequency, Outcrossing, And Male Sperm Size In Experimentally-Evolved C. Elegans, Brent William Bever

Dissertations and Theses

We provide the first controlled study of how male frequencies and rates of outcrossing evolve in response to mitonuclear mismatch by allowing replicate lineages of C. elegans nematodes containing either mitochondrial or nuclear mutations of electron transport chain (ETC) genes to evolve under three sexual systems: facultatively outcrossing (wildtype), obligately selfing, and obligately outcrossing. In partial support of a tenet of the mitonuclear sex hypothesis, which predicts that outcrossing will be favored in cases of mitonuclear mismatch, we found evolution of increased male frequency in at least one replicate line of all four ETC mutant backgrounds tested--nuclear isp-1, mitochondrial …


Four New Lithophilic Species Of Scorpiops Peters, 1861 (Scorpiones: Scorpiopidae) From Peninsular India, Shauri Sulakhe, Shubhankar Deshpande, Nikhil Dandekar, Anand Padhye, Deshabhushan Bastawade Sep 2021

Four New Lithophilic Species Of Scorpiops Peters, 1861 (Scorpiones: Scorpiopidae) From Peninsular India, Shauri Sulakhe, Shubhankar Deshpande, Nikhil Dandekar, Anand Padhye, Deshabhushan Bastawade

Euscorpius

Four new lithophilic species of Scorpiops Peters, 1861 (Scorpiopidae) have been described from peninsular India using an integrated taxonomic approach. Three species Scorpiops vrushchik sp. n., S. nagphani sp. n. and S. neera sp. n. have been described from northern Western Ghats and S. lioneli sp. n. is described from Deccan Plateau. S. vrushchik sp. n. is closely related to S. tenuicauda and S. telbaila and differs by a raw genetic divergence of 9.6-9.8% from S. tenuicauda and 11% from S. telbaila. S. nagphani sp. n. is closely related to S. lioneli sp. n. and S. maharashtraensis and differs by …


Phenotype Bias Determines How Natural Rna Structures Occupy The Morphospace Of All Possible Shapes, Fatme Ghaddar, Dr Kamaludin Dingle, Dr Petr Sulc, Prof Ard A. Louis Sep 2021

Phenotype Bias Determines How Natural Rna Structures Occupy The Morphospace Of All Possible Shapes, Fatme Ghaddar, Dr Kamaludin Dingle, Dr Petr Sulc, Prof Ard A. Louis

Undergraduate Research Symposium

The relative prominence of developmental bias versus natural selection is a long standing controversy in evolutionary biology. Here we demonstrate quantitatively that developmental bias is the primary explanation for the occupation of the morphospace of RNA secondary structure (SS) shapes. By using the RNAshapes method to define coarse-grained SS classes, we can measure the frequencies that non-coding RNA SS shapes appear in nature. Our main findings are firstly that only the most frequent structures appear in nature; the vast majority of possible structures in the morphospace have not yet been explored. Secondly, and perhaps more surprisingly, these frequencies are accurately …


A Reevaluation Of The Phylogeography Of The Chattahoochee Slimy Salamander (Plethodon Chattahoochee) Using Next-Generation Genomic Data, Jadin Cross Aug 2021

A Reevaluation Of The Phylogeography Of The Chattahoochee Slimy Salamander (Plethodon Chattahoochee) Using Next-Generation Genomic Data, Jadin Cross

Symposium of Student Scholars

The Plethodon glutinosus species complex is a group of large-bodied, lungless salamanders that are widespread across the eastern United States. Species in this group are morphologically cryptic and were originally delimited using allozyme data, but in most cases, the extent of contemporary gene flow between named taxa has not be rigorously evaluated. The Appalachian Mountains of northern Georgia are home to several members of this group—including P. glutinosus, P. teyahalee, P. chlorobryonis, and P. chattahoochee. P. chattahoochee has been found to be especially cryptic both morphologically and genetically as both intraspecific genetic variation and species boundaries within …


The Evolutionary Origins Of Autism Associated Genes And Their Role In Great Ape Socio-Communication, Azeeza Abdulrauf, Martin Hudson, Susan M.E. Smith, Jared P. Taglialatela Aug 2021

The Evolutionary Origins Of Autism Associated Genes And Their Role In Great Ape Socio-Communication, Azeeza Abdulrauf, Martin Hudson, Susan M.E. Smith, Jared P. Taglialatela

Symposium of Student Scholars

Single nucleotide polymorphisms (SNPs) play a major role in socio-communicative behavior. For this study, the focus is on autism associated OXTR, AVPR1A, and FOXP2 SNPs, and the role they play in great apes. Prior research on the OXTR, AVPR1A, and FOXP2 SNPs show that they affect behavior skills such as understanding and controlling emotion, understanding the emotions of others, and communications skills. Great apes, such as bonobos, chimpanzees, and gorillas are the model, since they are our closest relatives in the animal kingdom capable of understanding complex communication. Each gene has at least two SNPS that are investigated in the …


Laryngeal Vocals In Old World Locals: Air Sacs Usage In Bonobos, Chelsea Trenbeath Aug 2021

Laryngeal Vocals In Old World Locals: Air Sacs Usage In Bonobos, Chelsea Trenbeath

Symposium of Student Scholars

Except for humans, extant great apes have evolutionarily conserved lateral ventricular air sacs extending from laryngeal saccules. Humans are the only species of Hominidae that lack this anatomical feature attached to the primary vocal apparatus. As we are the only species that produces spoken language, this association has led to hypothesis that the loss of lateral ventricular air sacs was necessary for the evolution of spoken language. However, why these sacs are conserved in all other hominids remains unclear. Computer modeling has indicated that air sacs may increase resonance properties, but there are no data from great apes indicating which …


Foe To Friend: Parallel Domestication Of Ophiocordyceps From Fungal Parasite To Beneficial Symbiont In Cicadas, Jason Vailionis, Eric Rl Gordon, Chris Simon Aug 2021

Foe To Friend: Parallel Domestication Of Ophiocordyceps From Fungal Parasite To Beneficial Symbiont In Cicadas, Jason Vailionis, Eric Rl Gordon, Chris Simon

University Scholar Projects

Nutritional symbioses are integral to the survival and diversity of many insects. The majority of herbivorous insects in the order Hemiptera possess stable, inherited symbionts that produce essential amino acids and vitamins. However, instability has been observed in cicadas, with one bacterial symbiont, Hodgkinia cicadicola, being repeatedly replaced by a new fungal symbiont, Ophiocordyceps. The fungal symbionts are thought to be derived from parasitic Ophiocordyceps species, but little is known about these parasitic ancestors or how the transition from parasite to mutualist occurs. We used a combination of targeted amplified genes and metagenomic sequencing to investigate the evolution …


Case 3847 – Simopithecus Oswaldi Andrews, 1916 (Currently Theropithecus Oswaldi; Mammalia, Primates, Cercopithecidae), Proposed Conservation By Reversal Of Precedence With Cynocephalus Atlanticus Thomas, 1884., Eric Delson, David M. Alba, Stephen R. Frost, Dagmawit Abebe Getahun, Christopher C. Gilbert Aug 2021

Case 3847 – Simopithecus Oswaldi Andrews, 1916 (Currently Theropithecus Oswaldi; Mammalia, Primates, Cercopithecidae), Proposed Conservation By Reversal Of Precedence With Cynocephalus Atlanticus Thomas, 1884., Eric Delson, David M. Alba, Stephen R. Frost, Dagmawit Abebe Getahun, Christopher C. Gilbert

Publications and Research

The purpose of this application, under Articles 23.9.3 and 81.1 of the Code, is to conserve the usage of the species-group name Simopithecus oswaldi Andrews, 1916 by giving it precedence over its senior subjective synonym Cynocephalus atlanticus Thomas, 1884. Theropithecus is a common to dominant member of the extinct primate community across Africa after 4 million years ago (Jablonski & Frost, 2010) and often co-occurred with extinct humans (Hominini); fossils are also known rarely across Eurasia (Roberts et al., 2014). Most fossil samples are currently included in Theropithecus oswaldi (Andrews, 1916), which is often divided into chrono-geographic subspecies. Cynocephalus atlanticus …


Testing For Character Displacement Between Two Abundant Stream Fishes, Amber Nations Aug 2021

Testing For Character Displacement Between Two Abundant Stream Fishes, Amber Nations

Honors Theses

Character displacement is a pattern that can be used to explain differences between similar species in sympatric and allopatric situations. Gause’s Principle explains that a niche can only be occupied by one species at a time, so character displacement may be a way for similar species in the same habitat to shift resource use and compensate in order for the species to coexist. The Southeastern United States offers a unique opportunity to study this pattern because the diversity of freshwater fauna is quite high. However, the question of “How did this region become so diverse?” remains unanswered. One way for …


Investigation Into The Evolution Of Heterogeneity Within Secondary Replicons And Their Maintenance In Genus Variovorax, Christopher Ne Ville Aug 2021

Investigation Into The Evolution Of Heterogeneity Within Secondary Replicons And Their Maintenance In Genus Variovorax, Christopher Ne Ville

Electronic Theses, Projects, and Dissertations

Approximately 10% of all bacterial genomes sequenced thus far contain a secondary replicon. This considerable genetic reservoir contains many potentially mobilizable elements, allowing for the formation of many unique secondary replicons. This property of bacterial populations vastly increases the genomic diversity available to species that effectively take up and maintain these replicons. Members of the genus Variovorax have extensive heterogeneity in genome architecture, including sequenced isolates containing plasmids, megaplasmids, and chromids. Using available Illumina data on the NCBI database, we have completed these assemblies using 3rd generation sequencing methods on 17 members of this genus. We have sequenced, assembled, …


Alfred Russel Wallace Notes 18: Wallace On The Balance Of Nature, Charles H. Smith Aug 2021

Alfred Russel Wallace Notes 18: Wallace On The Balance Of Nature, Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (1823−1913) had a unique perspective on the ‘balance of nature’: he avoided classical thoughts on the subject, but nevertheless seems to have adopted elements of the ‘balance’ concept while acknowledging that irreversible change occurs at both the biological and environmental levels. Wallace’s position can be understood from his grounding in Humboldtian ‘equilibrium of forces’ thinking, and his turn toward ‘final causes’-based interpretations.