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

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 2021 University of South Florida

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 2021 Louisiana State University and Agricultural and Mechanical College

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 2021 University of South Florida

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 2021 University of Missouri-St. Louis

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 2021 Louisiana State University and Agricultural and Mechanical College

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 2021 Marshall University

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 2021 Portland State University

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 2021 Marshall University

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 2021 Gulf University for Science and Technology, Kuwait

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 2021 Kennesaw State University

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 2021 Kennesaw State University

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 2021 Kennesaw State University

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 2021 University of Connecticut - Storrs

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 2021 CUNY Lehman College

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 2021 The University of Southern Mississippi

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 2021 California State University - San Bernardino

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 2021 Western Kentucky University

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.


The Evolution Of Dietary Adaptations In Small Mammals: From Muscles To Microbes, Mark Thomas Swanson 2021 Louisiana State University and Agricultural and Mechanical College

The Evolution Of Dietary Adaptations In Small Mammals: From Muscles To Microbes, Mark Thomas Swanson

LSU Doctoral Dissertations

My dissertation provides critical insights on the pattern and process of evolution in front-end and back-end dietary adaptations of mammals. I found that the position of the rodent masseter muscle, a complex front-end adaptation that improves the efficiency of mechanical digestion, has convergently evolved numerous times, suggesting that selective pressure for this adaptation has been strong. For back-end adaptations, I found gut bacterial taxa that likely aid in chemical digestion of food have predictable associations with host diet across host species in natural environments. To detect patterns in gut microbial community structure that are related to host factors such as …


Comparative Genomics Methods And Applications, Emily N. Alden 2021 University of new mexico

Comparative Genomics Methods And Applications, Emily N. Alden

Biomedical Sciences ETDs

Virtually all fields of biology have benefited from the advancements in comparative genomics technologies, specifically in the study of evolution. In this dissertation I develop and use comparative genomic technologies to investigate the novel SARS-CoV-2 virus, assembly the first genome of the black lace domestic angelfish and identify germline genetic variants associated with altered breast cancer-specific survival. Our genome tiling array for the novel coronavirus presents a rapid and cost-effective method to sequence the entire viral genome and can be used to track the rapid evolution of viral variants in the population. The domestic angelfish is a member of the …


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