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Full-Text Articles in Biology

An Evaluation Of College Preparedness On Natural Selection Principles Following The Completion Of An Entry-Level Biology Course, Amy Bell Jan 2021

An Evaluation Of College Preparedness On Natural Selection Principles Following The Completion Of An Entry-Level Biology Course, Amy Bell

Murray State Theses and Dissertations

Abstract

Evolution education in secondary education has long been a topic of research. The level of knowledge and acceptance of students upon entering college has been studied using various methods; however, no study had provided the perception of preparedness from the student perspective nor had analyzed the individual Natural Selection principles. This study analyzed college freshmen (n=162) in an entry-level BIO 101 course. Participants were given the Conceptual Inventory of Natural Selection Instrument (CINSI) and perception survey questions upon completion of the course. The CINSI data was then analyzed for each of the four Natural Selection principles as well as …


A Cophylogenetic Analysis Of Fungus Gardening Ants And Their Symbiotic Fungi, Katherine Beigel Dec 2020

A Cophylogenetic Analysis Of Fungus Gardening Ants And Their Symbiotic Fungi, Katherine Beigel

Biology Theses

Fungus-growing ants (Tribe Attini) and their fungal cultivars share a 50-million-year coevolutionary history. Large scale phylogenetic analyses depict a strong co-phyletic signal among ants and their farmed fungi yet fungus sharing among unrelated ant lineages is somewhat widespread. An overview of sharing has been hampered by a lack of genetic markers that exhibit intraspecific variation and surveys across geographic regions. For example, previous studies have shown similar sequences of the internal transcribed spacer (ITS) region of fungus in different species of Trachymyrmex, suggesting that these ant species are farming the same fungal clone. To examine whether this was a …


Imagining The Internal Reproductive Environment: Function And Evolution Of The Drosophila Melanogaster Female Reproductive Tract, Caitlin Elizabeth Mcdonough-Goldstein Dec 2020

Imagining The Internal Reproductive Environment: Function And Evolution Of The Drosophila Melanogaster Female Reproductive Tract, Caitlin Elizabeth Mcdonough-Goldstein

Dissertations - ALL

Sexual reproduction involves complex coordination, and potentially competition, among the reproductive cells, fluids, and structures of all individuals involved. For internally fertilizing species, these interactions occur within the body of one sex, predominantly the female, or ovary-associated, reproductive tract. Thus, characterizing the dynamics of the female reproductive tract is critical to understanding the interactions that mediate reproductive success. Although there has been increasing movement toward revealing the active role of the female reproductive tract in shaping and influencing reproductive outcomes, our knowledge of this environment remains limited as a result of both historical biases and technical constraints. My dissertation advances …


Evolution Of Green Blood In New Guinea Lizards: Phylogenomics, Biogeography, And Comparative Genomics, Zachary Rodriguez Nov 2020

Evolution Of Green Blood In New Guinea Lizards: Phylogenomics, Biogeography, And Comparative Genomics, Zachary Rodriguez

LSU Doctoral Dissertations

Non-model organisms with evolutionary novelties and complex distributions can provide valuable insight into the mechanisms underlying biological diversity. Green blood is one of the most unusual vertebrate physiologies and has repeatedly evolved in lizards from the megadiverse island of New Guinea. An unusually high concentration of the toxic green bile pigment biliverdin causes the green coloration of these lizards' blood, muscles, and bones. This dissertation uncovered the complex history of this novel trait (Chapter 2), identified protein-coding sequences that underlie green blood in lizards (Chapter 3), and explored evolutionary processes that drive genetic diversity in high-elevation lizards. To accurately trace …


Trophic Cascades Alter Eco-Evolutionary Dynamics And Body Size Evolution, Thomas M. Luhring, John Delong Nov 2020

Trophic Cascades Alter Eco-Evolutionary Dynamics And Body Size Evolution, Thomas M. Luhring, John Delong

School of Biological Sciences: Faculty Publications

Trait evolution in predator–prey systems can feed back to the dynamics of interacting species as well as cascade to impact the dynamics of indirectly linked species (eco-evolutionary trophic cascades; EETCs). A key mediator of trophic cascades is body mass, as it both strongly influences and evolves in response to predator–prey interactions. Here, we use Gillespie ecoevolutionary models to explore EETCs resulting from top predator loss and mediated by body mass evolution. Our four-trophic-level food chain model uses allometric scaling to link body mass to different functions (ecological pleiotropy) and is realistically parameterized from the FORAGE database to mimic the parameter …


The Evolution Of Life Histories And Phenotypic Plasticity Across Environmental Gradients In Daphnia Sp., Michelle Renee Swan Packer Aug 2020

The Evolution Of Life Histories And Phenotypic Plasticity Across Environmental Gradients In Daphnia Sp., Michelle Renee Swan Packer

Biology Dissertations - Archive

Understanding how environmentally-induced variation ultimately leads to speciation is a main component of evolutionary ecology. This dissertation uses Daphnia in experimental and comparative studies to address several theoretical questions concerning the role of phenotypic plasticity in the evolutionary process. Specifically, I explore novel environmental factors which induce plasticity and investigate the plastic response across systems to determine general hypotheses for understanding the mechanisms which may be involved. Additionally, this dissertation provides empirical results which add to the body of research investigating the transition between environmentally induced phenotypes and genetic adaptation. The results of this body of work show that ancestral …


Identifying Positive Selection In Multiple Subspecies Of Xylella Fastidiosa, Daniel Doroteo Flores Aug 2020

Identifying Positive Selection In Multiple Subspecies Of Xylella Fastidiosa, Daniel Doroteo Flores

Theses and Dissertations

For this study, we will be looking to identify positive selection in eight genomes of the bacterial plant pathogen Xylella fastidiosa. A previous study used a branching method that identified 2 genes with positive selection along with a site-specific method identifying 34 genes showing positive selection. This current study focused specifically on the site-specific method, resulting in 28 genes (of 1,039 tested) showing positive selection. Of the 28 genes showing positive selection, 12 of them come from the pathogenicity, virulence and cellular structural categories. The remaining genes are found in the biosynthesis, metabolism, macro metabolism, and cellular process categories. …


Chronic And Acute Respiratory Pathogens: Evolutionary And Epidemiological Characteristics Of Tuberculosis, Influenza-Like Illness, And Covid-19, Julie Allison Spencer Jul 2020

Chronic And Acute Respiratory Pathogens: Evolutionary And Epidemiological Characteristics Of Tuberculosis, Influenza-Like Illness, And Covid-19, Julie Allison Spencer

Biology ETDs

Tuberculosis and influenza-like illness cause major disease burden for humans. In our first study, we conducted a pangenome analysis of 67 Mycobacterium tuberculosis genomes from Peru. We supported the paradigm that M. tuberculosis is highly clonal; however, a small amount of genetic diversity originates from infrequent recombina- tion events. In our second study, we reviewed the literature for parameters of five common viruses that contribute to influenza-like illness: influenza, RSV, rhinovirus, human coronavirus, and adenovirus. We found that their epidemiological parameters vary considerably, and can have broad ranges; their basic transmission rates are the most important for model outcomes. When …


Characterization And Analysis Of The Avian Epidermal Differentiation Complex And Implications In Feather Evolution, Anthony Chastine Davis Jul 2020

Characterization And Analysis Of The Avian Epidermal Differentiation Complex And Implications In Feather Evolution, Anthony Chastine Davis

Theses and Dissertations

Since the most recent major mass-extinction event ~65 million years ago, birds have expanded to now occupy a wide range of habitats and exhibit diverse lifestyles. A major reason for this evolutionary success is the mechanical resilience and diversity of their epidermal appendages such as feathers, scales, and beaks. The diversity of these appendages, specifically feathers has played a critical role in their evolutionary success. The feathers of birds vary substantially across different species, as well as at different life stages and anatomical locations on an individual bird. Several of the genetic elements involved in the development and structure of …


Plant Evolution And Urbanization: Quantifying The Effects Of Natural Selection In Shaping Shepherd’S Purse (Capsella Bursa-Pastoris) Populations In New York City, Rebecca Panko May 2020

Plant Evolution And Urbanization: Quantifying The Effects Of Natural Selection In Shaping Shepherd’S Purse (Capsella Bursa-Pastoris) Populations In New York City, Rebecca Panko

Dissertations

The aim of this study is to quantify the effects of natural selection in shaping Capsella bursa-pastoris populations along an urban-rural gradient in New York City.

A reciprocal transplant experiment with 168 lab-germinated C. bursa-pastoris seedlings from both urban and rural populations are grown in eight paired home and away sites distributed throughout the New York metropolitan area. Sites are visited approximately thirteen times to record plant fitness. There is evidence for local adaptation of urban populations: urban plants have longer reproductive durations and produce more seed pods in urban environments. These findings suggest that urban plants are better adapted …


A Genomic Analysis Of Bobcat Populations In North America With A Comparison To The Canada Lynx: An Assessment Of Local Adaptation To Unique Ecoregions And Phylogeography, Jennifer C. Broderick May 2020

A Genomic Analysis Of Bobcat Populations In North America With A Comparison To The Canada Lynx: An Assessment Of Local Adaptation To Unique Ecoregions And Phylogeography, Jennifer C. Broderick

Electronic Theses and Dissertations

Bobcats (Lynx rufus) are an ecologically and genetically diverse species with a large contiguous range throughout North America. The species not only has a wide array of phenotypic variation compared to other mammals, but shows marked adaptability across ecozones with differing ecological influences. It is these various selective pressures in distinctive parts of the continent that have likely led to localized adaptations within the bobcat metapopulations. The species is also marked by its ability to maintain connectivity and populations in anthropogenically developed areas, an advantage it has over other felids, including its close relative the Canada lynx ( …


Genetic Analysis Of Flower Color Differences Between A Hummingbird-Pollinated And A Self-Pollinated Monkeyflower (Mimulus) Species, Caitlin Foster May 2020

Genetic Analysis Of Flower Color Differences Between A Hummingbird-Pollinated And A Self-Pollinated Monkeyflower (Mimulus) Species, Caitlin Foster

University Scholar Projects

Flower color plays an important role in pollinator discrimination and speciation. Understanding the genetic contributions to flower color differences between two closely related species, Mimulus cardinalis and Mimulus parishii, can improve understanding of how they developed different pollination syndromes and diverged from a recent common ancestor. M. cardinalis is hummingbird-pollinated and has large, bright red flowers while M. parishii is self-pollinated and has small, pale pink flowers. An F2 hybrid population between these two species was created to establish a platform for analysis of the genetic architecture controlling the differences in anthocyanin pigmentation. Statistical analysis of anthocyanin concentration distribution …


Teaching Natural And Artificial Selection In Production Agriculture, Madhav P. Nepal, Clayton W. Scott Mar 2020

Teaching Natural And Artificial Selection In Production Agriculture, Madhav P. Nepal, Clayton W. Scott

iLEARN Teaching Resources

In this lesson, students will learn how natural selection and artificial selection impact both production agriculture and biological sciences. A natural selection is a mechanism that favors heritable traits that increase species survival and reproduction. Artificial selection is a selective breeding, where humans select for desirable traits in agricultural products.


The Bioethical Significance Of “The Origin Of Man’S Ethical Behavior” (October 1941, Unpublished) By Ernest Everett Just And Hedwig Anna Schnetzler Just, Theodore Walker Jr. Jan 2020

The Bioethical Significance Of “The Origin Of Man’S Ethical Behavior” (October 1941, Unpublished) By Ernest Everett Just And Hedwig Anna Schnetzler Just, Theodore Walker Jr.

Journal of the South Carolina Academy of Science

Abstract –

E. E. Just (1883-1941) is an acknowledged “pioneer” in cell biology, and he is perhaps the pioneer in study of egg cell fertilization. Here we discover that Just also made pioneering contributions to general biology and evolutionary bioethics.

Within Just’s published contributions to observational cell biology, there are substantial fragments of his theory of ethical behavior, a theory with roots in cell biology. In addition to such previously available fragments, Just’s fully developed theory is now available. This recently discovered unpublished book-length manuscript argues for the biological origins of ethical behavior (evolving from cells to humans, within a …


Phylogenetic Analysis Of Sars-Cov-2 Genomes In Turkey, Ogün Adebali̇, Ayli̇n Bi̇rcan, Defne Çi̇rci̇, Burak İşlek, Zeynep Kilinç, Berkay Selçuk, Berk Turhan Jan 2020

Phylogenetic Analysis Of Sars-Cov-2 Genomes In Turkey, Ogün Adebali̇, Ayli̇n Bi̇rcan, Defne Çi̇rci̇, Burak İşlek, Zeynep Kilinç, Berkay Selçuk, Berk Turhan

Turkish Journal of Biology

COVID-19 has effectively spread worldwide. As of May 2020, Turkey is among the top ten countries with the most cases. A comprehensive genomic characterization of the virus isolates in Turkey is yet to be carried out. Here, we built a phylogenetic tree with globally obtained 15,277 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes. We identified the subtypes based on the phylogenetic clustering in comparison with the previously annotated classifications. We performed a phylogenetic analysis of the first 30 SARS-CoV-2 genomes isolated and sequenced in Turkey. We suggest that the first introduction of the virus to the country is earlier …


Identification Of The Nucleotide Substitutions In 62 Sars-Cov-2 Sequences From Turkey, Ayşe Banu Demi̇r, Domenico Benvenuto, Yusuf Hakan Abacioğlu, Silvia Angeletti, Massimo Ciccozzi Jan 2020

Identification Of The Nucleotide Substitutions In 62 Sars-Cov-2 Sequences From Turkey, Ayşe Banu Demi̇r, Domenico Benvenuto, Yusuf Hakan Abacioğlu, Silvia Angeletti, Massimo Ciccozzi

Turkish Journal of Biology

A previously unknown coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been shown to cause coronavirus disease 2019 (COVID-19) pandemic. The first case of COVID-19 in Turkey has been declared in March 11th, 2020 and from there on, more than 150,000 people in the country have been diagnosed with the disease. In this study, 62 viral sequences from Turkey, which have been uploaded to GISAID database, were analyzed by means of their nucleotide substitutions in comparison to the reference SARS-CoV-2 genome from Wuhan. Our results indicate that the viral isolates from Turkey harbor some common mutations with the viral …


Group Ii Introns : Evolution, Structure And Function, Xiaolong Dong Jan 2020

Group Ii Introns : Evolution, Structure And Function, Xiaolong Dong

Legacy Theses & Dissertations (2009 - 2024)

Group II introns are mobile, self-splicing ribozymes found in bacteria, archaea and eukaryotic organelles. They are widely believed to be the progenitors of the eukaryotic spliceosomal introns and retroelements. Yet many structural and evolutionary aspects of group II introns remain elusive. Indeed, while group II introns are the putative forerunners of spliceosomal introns in eukaryotes, they are notably absent in the nuclear genomes and a large portion of prokaryotes. Furthermore, although the architecture of a post-catalytic group II intron holoenzyme containing both the RNA and the bound intron encoded protein (IEP) has been solved by cryo-electron microscopy (cryo-EM), the interactions …


The Evolution Of Dragons, Laura J. Mayfield Jan 2020

The Evolution Of Dragons, Laura J. Mayfield

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Dragons have been depicted in human art as early as 4500 BCE. For centuries, these fantasy creatures have inspired countless folk and fantasy tales, as well as appearing in the art of different cultures around the world. Now there are thousands of different depictions of these huge, flying, fire-breathing lizards, but are any of them possible? In this study, I reference peer-reviewed scientific articles, phylogenetic analysis, and paleoart studies to create biologically-sound dragons. Basing the dragon lineage on a real branch of webbed-winged scansoriopterygids—an extinct family of climbing and gliding maniraptoran dinosaurs—I explored the possible wing-structure, fire-breathing abilities, and effects …


Trade-Offs Between Morphology And Thermal Niches Mediate Adaptation In Response To Competing Selective Pressures, Stella F. Uiterwaal, Ian T. Lagerstrom, Thomas M. Luhring, Miranda E. Salsbery, John P. Delong Jan 2020

Trade-Offs Between Morphology And Thermal Niches Mediate Adaptation In Response To Competing Selective Pressures, Stella F. Uiterwaal, Ian T. Lagerstrom, Thomas M. Luhring, Miranda E. Salsbery, John P. Delong

School of Biological Sciences: Faculty Publications

Abstract

The effects of climate change—such as increased temperature variability and novel predators—rarely happen in isolation, but it is unclear how organisms cope with multiple stressors simultaneously. To explore this, we grew replicate Paramecium caudatum populations in either constant or variable temperatures and exposed half to predation. We then fit thermal performance curves (TPCs) of intrinsic growth rate (rmax) for each replicate population (N = 12) across seven temperatures (10°C–38°C). TPCs of P. caudatum exposed to both temperature variability and predation responded only to one or the other (but not both), resulting in unpredictable outcomes. These changes in …


Trade-Offs Between Morphology And Thermal Niches Mediate Adaptation In Response To Competing Selective Pressures, Stella F. Uiterwaal, Ian T. Lagerstrom, Thomas M. Luhring, Miranda E. Salsbery, John P. Delong Jan 2020

Trade-Offs Between Morphology And Thermal Niches Mediate Adaptation In Response To Competing Selective Pressures, Stella F. Uiterwaal, Ian T. Lagerstrom, Thomas M. Luhring, Miranda E. Salsbery, John P. Delong

School of Biological Sciences: Faculty Publications

The effects of climate change—such as increased temperature variability and novel predators—rarely happen in isolation, but it is unclear how organisms cope with mul- tiple stressors simultaneously. To explore this, we grew replicate Paramecium caudatum populations in either constant or variable temperatures and exposed half to predation. We then fit thermal performance curves (TPCs) of intrinsic growth rate (rmax) for each replicate population (N = 12) across seven temperatures (10°C–38°C). TPCs of P. caudatum exposed to both temperature variability and predation re- sponded only to one or the other (but not both), resulting in unpredictable outcomes. …


Hybrid Zone Barriers Comparative Data Set, David L. Field Jan 2020

Hybrid Zone Barriers Comparative Data Set, David L. Field

Research Datasets

Many recent studies have addressed the mechanisms operating during the early stages of speciation, but surprisingly few studies have tested theoretical predictions on the evolution of strong reproductive isolation (RI). To help address this gap, we first undertook a quantitative review of the hybrid zone literature for flowering plants in relation to reproductive barriers. Then, using Populus as an exemplary model group, we analysed genome-wide variation for phylogenetic tree topologies in both early- and late-stage speciation taxa to determine how these patterns may be related to the genomic architecture of RI. Our plant literature survey revealed variation in barrier complexity …


Investigating The Roles Of Bacterial Endosymbionts In The Evolution Of Adelgidae (Hemiptera: Sternorrhyncha), Kathryn M. Weglarz Dec 2019

Investigating The Roles Of Bacterial Endosymbionts In The Evolution Of Adelgidae (Hemiptera: Sternorrhyncha), Kathryn M. Weglarz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Insects form close partnerships, or symbioses, with bacteria. These partnerships allow the insects to use resources that would be unavailable to them otherwise. Certain insects, hemipterans, are able to feed on nutrient-poor plant-sap because these bacteria supplement their diets. While this association is beneficial for both the insect and bacteria, it also comes with consequences: the genomes of bacterial symbionts typically undergo extreme degradation, becoming small and lacking many genes necessary for typical bacterial functioning. In the Hemiptera, aphids, mealybugs, cicadas, true bugs, and their relatives, these bacterial partnerships tend to be stable over millions of years. However, adelgids (Aphidoidea: …


Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey R. Gadek Nov 2019

Dynamics Of Avian Elevational Ranges Reveal Hidden Evolutionary Forces, Chauncey R. Gadek

Biology ETDs

The distribution of life across the Andes mountains reflects historical elevational-range contraction and expansion. Whereas contraction implies specialization, expansion requires overcoming hidden barriers. Three eco-evolutionary phenomena may drive patterns in rates of elevational range evolution: (1) The Dobzhansky-MacArthur Phenomenon (DMP) predicts lower rates of upward expansion with harsher physical conditions, while downward expansion increases with lower diversity; (2) the evolutionary tendency toward specialization predicts contraction increases when ranges are broad; and (3) natural selection for respiratory performance could suppress expansion across mid-elevations due to gene-environment mismatch. We modeled elevational range shifts of Neotropical landbirds. Contrary to the DMP, upward expansion …


The Functional, Ecological, And Evolutionary Morphology Of Sea Lampreys (Petromyzon Marinus), Bradley Morgan Wood Nov 2019

The Functional, Ecological, And Evolutionary Morphology Of Sea Lampreys (Petromyzon Marinus), Bradley Morgan Wood

LSU Doctoral Dissertations

Lampreys (Petromyzontiformes) are jawless vertebrates with an evolutionary history lasting at least 360 million years and are often used in comparisons with jawed vertebrates because some of their morphological aspects, such as the segmented trunk musculature with curved myosepta and a non-mineralized skeleton fibrous skeleton, are thought to resemble the condition of early vertebrates before the evolution of jaws. Although earlier authors studied the morphology of the skeleto-muscular system of the trunk of lampreys, their studies are not detailed and complete enough to allow a functional and biomechanical analysis that is needed as a basis for modeling the mechanics of …


Getting Back To Nature: Feralization In Animals And Plants, Eben Gering, Darren Incorvaia, R. Henriksen, Jeffrey Conner, Thomas Getty, Dominic Wright Sep 2019

Getting Back To Nature: Feralization In Animals And Plants, Eben Gering, Darren Incorvaia, R. Henriksen, Jeffrey Conner, Thomas Getty, Dominic Wright

Biology Faculty Articles

Formerly domesticated organisms and artificially selected genes often escape controlled cultivation, but their subsequent evolution is not well studied. In this review, we examine plant and animal feralization through an evolutionary lens, including how natural selection, artificial selection, and gene flow shape feral genomes, traits, and fitness. Available evidence shows that feralization is not a mere reversal of domestication. Instead, it is shaped by the varied and complex histories of feral populations, and by novel selection pressures. To stimulate further insight we outline several future directions. These include testing how ‘domestication genes’ act in wild settings, studying the brains and …


Comparative Brain Anatomy Of Lamniform Sharks (Elasmobranchii: Lamniformes) And Its Implications To Function, Behavioral Ecology, And Evolution, Francesco Guzzo Aug 2019

Comparative Brain Anatomy Of Lamniform Sharks (Elasmobranchii: Lamniformes) And Its Implications To Function, Behavioral Ecology, And Evolution, Francesco Guzzo

College of Science and Health Theses and Dissertations

Understanding the diversity of brain morphology is important to understand the evolution of cognitive ability and how ecology and phylogeny have influenced the variation in brain complexity. I examined the morphological variation of the brain in the shark order Lamniformes based on museum specimens and literature. Where I illustrate a wide range of morphological diversity in lamniform brains, my study shows that there is a strong positive correlation between brain size and body size that sharks with a larger brain tend to have a more foliated cerebellum, but that the body weight over brain weight did not correlate with cerebellar …


Quantifying The Predictability Of Evolution At The Genomic Level In Lycaeides Butterflies, Samridhi Chaturvedi Aug 2019

Quantifying The Predictability Of Evolution At The Genomic Level In Lycaeides Butterflies, Samridhi Chaturvedi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Stephen Jay Gould, a great scientist and evolutionary biologists, suggested that if we could replay the tape of life, we would not have observed similar course of events because evolution is stochastic and if affected by several events. Since then, the possibility that evolution is repeatable or predictable has been debated. Studies using large-scale evolution experiments, long-term data for individual populations, and controlled experiments in nature, have demonstrated phenotypic and genetic convergence in several taxa. These studies suggest that despite some randomness, predictable evolutionary patterns can emerge on a large temporal and spatial scale. However, a few cases also exist …


Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella Jul 2019

Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella

Biology ETDs

At high latitudes, climatic oscillations have triggered repeated episodes of organismal divergence by geographically isolating populations. For terrestrial species, extended isolation in glacial refugia – ice-free regions that enable terrestrial species persistence through glacial maxima – is hypothesized to stimulate allopatric divergence. Alternatively, upon glacial recession, divergent populations expanded from independent glacial refugia and often contacted other diverging populations. In the absence of reproductive isolating mechanisms, this biogeographic process may trigger hybridization and ultimately, gene flow between divergent taxa. My dissertation research aims to understand how these episodic periods of isolation and contact have impacted the evolution of high latitude …


A Race Against Time: Deciphering Evolution And Describing New Species Of Threatened Tropical Stick Insects (Phasmatodea), Michael F. Whiting Jun 2019

A Race Against Time: Deciphering Evolution And Describing New Species Of Threatened Tropical Stick Insects (Phasmatodea), Michael F. Whiting

Journal of Undergraduate Research

Funding was received in 2016 to support mentored research into the phylogeny and evolution of stick insects. Specific goals include providing students with scientific design experience, field-based research experience, collections-based experience, molecular lab experience, bioinformatics experience, and experience in presentation at national meetings and publication in peer reviewed journals. One particular focus was to describe new stick insect species, but it became clear very quickly that the phylogeny portion of this work was essential before any new species could be described, so we concentrated our efforts on stick insect phylogeny. The following is a brief summary of accomplishments.


Guided Evolution To Expand The Host Range In Phages, Jamison Walker, Sandra Hope Jun 2019

Guided Evolution To Expand The Host Range In Phages, Jamison Walker, Sandra Hope

Journal of Undergraduate Research

My project proposal included the use of Darwin’s theory of evolution by natural selection to determine if genetic mutations will arise in Bacteriophages that would allow them to infect related strains in a species of bacteria. Bacteriophages naturally have a target host range that they can infect. Within species of bacteria, the phage has tail receptors that allow it to infect specific strains. The other strains of the bacteria will be unaffected by the phage. In phage therapy, multiple phages with varied host ranges are chosen to combat this problem. Some phages are more effective than others in killing a …