Evolution Commons^™

The Descent Of Anolis: Assemblages, Convergence, And Ecomorphological Evolution, Christopher G. Anderson

Biology ETDs

The evolutionary outcomes we observe in modern organisms, particularly associations between phenotypes and environments, have been and remain an invaluable tool in interpreting the biological phenomena that shape our world. In the following chapters, I leverage a comprehensive phylogenetic and morphological dataset for 351 species comprising a diverse group of arboreal lizards, the Anolis clade, to explore how communities and morphologies evolve. First, I characterized patterns among coexisting lineages of Anolis to reveal a general pattern of phylogenetic relatedness among lineages comprising assemblages and identify differences attributable to a biogeographic variable. Then I examined the morphological consequences associated with the …

Teaching Evolutionary Principles With Ai Image Generators, Jacqueline Garnett

Generative AI Teaching Activities

The purpose of this assignment is for students to practice constructing phylogenies using the principle of parsimony. In this activity, students will use an AI Image Generator to create a grid of images of the same organism and identify a series of traits that vary to build a possible phylogenetic tree.

Parental Environnement Influences Offspring Gene Expression In The Olympia Oyster, Ostrea Lurida., Mark S. Yeats

LSU Master's Theses

The Olympia Oyster is the only native oyster species on the Pacific coast of North America. Seasonality in water temperatures across this threatened species’ broad and fragmented range has been linked to its development, reproductive timing, reproductive activity, growth, and survival rates. Recent evidence suggests parental environments can have carry-over effects on larval growth and respiration rates in response to temperature. In this study, we utilized transcriptomic methods to identify the underlying mechanisms of this cross-generation plasticity. Sequence libraries of adult ctenidia tissue and pooled larval replicates were extracted and spawned from hatchery raised oysters of the same parentage immediately …

The Morphological Evolution Of The Inner Ear In Lacertoidea (Squamata), Cristian Hernandez

Biology Dissertations - Archive

The popularization of high-resolution computed tomography(HRCT) has produced a revolution in the field of comparative anatomy. This technology allows us to reach a level of morphological detail in our observations that has never been possible previously. Now we can perform digital dissections isolating structures of interest such as individual bones, soft tissue organs, and even generate 3D models of body cavities (endocasts) such as the braincase and inner ear. Encompassed with the progress of the HRCT, 3D geometric morphometrics have emerged as a common tool to address morphological questions in a statistical context that outperforms the traditional 2D geometric morphometrics. …

A Case Of Incipient Budding Speciation In The California Floristic Province, Infraspecific Divergence In Abronia Villosa, Eli J. Allen

Cal Poly Humboldt theses and projects

Physical barriers to gene flow are the traditional evidence for species divergence. Conversely, there has been increasing acknowledgment of speciation in the face of gene flow as an evolutionary process. Budding speciation involves peripheral populations adapting to local ecological conditions, thereby budding off from a widespread progenitor species. Budding speciation is distinguished by ecological divergence and is generally evidenced by asymmetrical range size and nested phylogenetic relationships of sister species. The narrow endemic Abronia villosa var. aurita is adapted to montane sandy washes adjacent to its widespread sister variety, the desert dwelling var. villosa. Here, I tested the hypothesis …

Investigation Of L-Serine Synthesis And Transport As Stabilizing Feedback Mechanisms Within The Tsetse-Wigglesworthia Symbiosis, Ryan Phillips

Graduate Theses, Dissertations, and Problem Reports (ETD)

Tsetse flies (Glossina morsitans), which are the obligate vectors of Old-World trypanosomes (Trypanosoma spp.) that cause African trypanosomiasis, have a bacteriome that houses the intracellular endosymbiont Wigglesworthia glossinidia. The ancient coevolution of these species has led to the integration of Wigglesworthia metabolism into tsetse physiology and a subsequent reliance on nutrient exchange for maintaining the fitness of both partners. The establishment of this obligate mutualism has facilitated the emergence of feedback mechanisms that stabilize the symbiosis, such as that which involves the exchange of L-serine and B vitamins. The Gammaproteobacteria Wigglesworthia supplement B vitamins lacking …

Functional Investigation Of Shaggy, An Inhibitor Of Canonical Wnt Signaling, In The Tardigrade Hypsibius Exemplaris, Raul A. Chavarria

UNF Graduate Theses and Dissertations

Tardigrades have a highly simplified anteroposterior (AP) axis. The mechanisms that regulate the development of this secondarily simplified AP axis are not known. In many animals, the canonical Wnt (cWnt) signaling pathway regulates primary axis establishment through antagonistic interactions with inhibitors of cWnt signaling. This study investigated the roles of shaggy, an inhibitor of cWnt signaling, in regulating development in the tardigrade Hypsibius exemplaris. Gene expression patterns of shaggy and other components of the cWnt signaling pathway were analyzed alongside markers of anterior and posterior identity using Hybridization Chain Reaction in situ in H. exemplaris. RNA interference …

High-Quality Dietary Protein (Essential Amino Acids Matched To Reproductive Needs) Partially Breaks The Lifespan And Reproduction Trade-Off In Lubber Grasshoppers, Emma Kordek

UNF Graduate Theses and Dissertations

Finding interventions to break the trade-off between reproduction and lifespan can provide insight into physiological limitations of animals. Effects of dietary protein quality on the trade-off are currently unclear, but clarity could lead to better designed diets that match animal needs. Dietary amino acid blends matching yolk proteins support reproduction and extend lifespan in fruit flies. To test if this is conserved across species, we matched dietary amino acids to vitellogenin to test reproduction and lifespan in adult females of the lubber grasshopper. Specifically, we compared varying degrees of protein quality by manipulating dietary essential amino acids. We identified a …

Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil

Electronic Theses and Dissertations

Understanding how innocuous organisms can evolve to be pathogenic to humans is of increasing global concern. Further, understanding how existing pathogens may evolved to be more virulent is also vital to our ability to provide healthcare to people afflicted with diseases that promote chronic bacterial infections, such as cystic fibrosis. With the rise of antibiotic resistance in both bacteria and fungi it is paramount that new therapeutics are identified. Understanding what mutations occur that result in increased virulence in microbes can potentially provide new targets for antimicrobial drugs to combat antibiotic resistance. The Coincidental Evolution Hypothesis is a fundamental hypothesis …

Lizard Communities In A Shifting Landscape: The Current State Of Insectivorous Lizard Communities In The Jornada Basin Between Grassland, Mesquite Dune, And Creosote Bush Habitats In A Semi-Arid Landscape Undergoing Shrubification, Julie Marie Schlichte

Open Access Theses & Dissertations

Lizard communities in arid lands can act as model systems of how diversity and abundance are impacted in the face of ongoing climate variability and change, as they are sensitive to shifts in precipitation, temperature, and changing vegetation structure. The main research question we hope to answer is how the community composition of lizards varies between dominant vegetation types (Mesquite dunes, grasslands, and Creosote Bush flats). Nine sites (3 of each dominant vegetation type) with 16 pitfall traps each (n = 144) were surveyed from June 2016 -- June 2017. 12 lizard species were captured, consisting of 923 total captures …

Activity Patterns Of Whiptail Lizards (Aspidoscelis) Found In The Northern Chihuahuan Desert, Guillermo Alvarez

Open Access Theses & Dissertations

Traditional lizard pitfall traps were modified to allow organisms to escape, while collecting valuable ecological data. Modified camera traps were capable of detecting the same species as traditional traps in a semi-arid environment, without posing the associated mortality risks. Pitfall-camera traps were used to sample the activity of the Side-blotched Lizard (Uta stansburiana) and the Southwestern Fence Lizard (Sceloporus cowlesi) in an urban wetland during four continuous years. Evaluations on activity pattern and the activity overlap between the two species revealed extensive overlap, with minor but significant seasonal shifts mediating coexistence. Traps were also effective at detecting other reptiles, invertebrates, …

Individual And Population Age Impact Social Behavior And Network Structure In A Long-Lived Insect, P. A. Cook, R. A. Costello, Vincent A. Formica, E. D. Brodie Iii

Biology Faculty Works

Social behaviors vary among individuals, and social networks vary among groups. Understanding the causes of such variation is important for predicting or altering ecological processes such as infectious disease outbreaks. Here, we ask whether age contributes to variation in social behavior at multiple levels of organization: within individuals over time, among individuals of different ages, among local social environments, and among populations. We used experimental manipulations of captive populations and a longitudinal dataset to test whether social behavior is associated with age across these levels in a long-lived insect, the forked fungus beetle (Bolitotherus cornutus). In cross-sectional analyses, …

Go Big Or Go Home: Divergence In Morphology And Behavior Between Island And Islet Populations Of The San Cristóbal Lava Lizard (Microlophus Bivittatus), Emilio J. Mancero

Masters Theses

Rapid divergence in body size is a well-documented phenomenon among island species, associated with macroevolutionary processes of diversification and adaptive radiation. The effect of insularity in determining larger body size as an optimal phenotype is primarily attributed to lower predation and greater intraspecific competition on islands. Our study examined interpopulation variation in morphology, social behavior and predator avoidance in Galápagos lava lizards endemic to San Cristóbal island (Microlophus bivittatus), and the nearby islet Isla Lobos. Islet populations have fewer competitors than those on the island, where native and introduced predators are abundant. We simulated interactions with predators and …

Resolving The Paradox Of Polyploidy: Underexplored Facets Of Polyploid Plants, Benjamin P. Gerstner

Biology ETDs

Polyploidy, or whole genome duplication, is a common phenomenon in plants, but the establishment and persistence of mixed-ploidy populations remains a paradox. This dissertation explores factors that contribute to the persistence and establishment of mixed-ploidy populations in nature. The first chapter investigates the role of unreduced gametes in neopolyploid establishment and finds that variability in their formation rate can have a significant impact on polyploid establishment and persistence. The second chapter searches for evidence of soil microbes exhibiting ploidy-specificity, a pre-condition for microbe-mediated niche differentiation, a possible stabilizing mechanism contributing to ploidy coexistence. Finally, the third chapter tests for microbe-mediated …

The Importance Of Soil Carbon In Large-Scale Shrub Removal Practices In The Chihuahuan Desert, Kathleen Schaeffer

Open Access Theses & Dissertations

Shrub encroachment is a worldwide phenomenon that affects multiple biomes at different ecological and anthropogenic levels. In dryland ecosystems, shrub encroachment is a noted concern amongst land managers, as it can lead to a loss of soil resources and biodiversity. To mitigate the negative effects of shrub encroachment in Drylands, land managers can implement large-scale shrub removal practices. These land restoration practices can shift landscapes to novel ecosystems, where resulting plant communities can vary following treatments. Grass recovery or increasing herbaceous cover is often a primary goal of these treatments, however predicting which sites may show higher grass responses to …

Phylogeny And Taxonomy Of Genus Physaria In North America, Binoshi Hettihewa

Theses

Physaria is a genus of ~108 species belonging to family Brassicaceae that is predominantly distributed in Western North America, but one species occurs in Arctic Russia and Northern Canada and several species occur in South America. Regardless of the vast number of species in the genus, the genus lacks a well-resolved phylogeny representing many taxa, partially because phylogeny reconstruction is complicated by the fact that many species of Physaria vary in chromosome numbers and ploidy levels. In chapter 1, we review how polyploids are formed and become established and summarize what is known about variation in chromosome number and ploidy …

Testing The Urban Dulling Hypothesis In An Iridescent Passerine Bird, Joanna Gresham

Master of Science in Integrative Biology Theses

Urbanization has brought grave consequences that lead to declines in many species; however, some species thrive in urban ecosystems. This allows us the opportunity to study evolution in real time, as species adapt and change in a new setting. Novel urban ecosystems have led to phenotypic divergence between urban and rural populations. There is a rich body of literature on how songbirds are affected by urbanization, however divergent signaling behaviors are less well understood. Urban color homogenization is well-documented in carotenoid-colored species. However, iridescent plumage is understudied in general, and little is understood about how environmental changes shape iridescent plumage. …

Phylogeographic History Of The Leaf-Eared Mouse, Phyllotis Xanthopygus Complex, Tabitha R. Mcfarland

Biology ETDs

Museum collections provide essential biodiversity sampling needed to understand the species limits, phylogeny, and biogeographic history of mammals, all key features of the foundation for comparative analyses in ecology and evolution. We add to this framework a diverse assemblage of species of leaf-eared mice (genus Phyllotis) in South America and then focus on the Phyllotis xanthopygus complex by combining available mitochondrial sequence (cytochrome b; cytb) data (351 GenBank samples) with 52 newly sequenced museum samples from the northern extent of this complex’s range (51 from Bolivia and 1 from northern Chile) to reconstruct evolutionary relationships using maximum …

Mitogenomes Revealed The History Of Bison Colonization Of Northern Plains After The Last Glacial Maximum, Igor V. Ovtchinnikov, Blake Mccann

Biology Faculty Publications

American bison demonstrated differential patterns of extinction, survival, and expansion since the terminal Pleistocene. We determined population dynamics of the Northern Great Plains bison using 40 mitochondrial genomes from radiocarbon dated remains with the age ranging from 12,226 to 167 calibrated years before present. Population dynamics correlated with environmental and anthropogenic factors and was characterized by three primary periods: terminal Pleistocene population growth starting 14,000 years ago, mid Holocene demographic stability between 6700 and 2700 years ago, and late Holocene population decline in the last 2700 years. Most diversification of mtDNA haplotypes occurred in the early Holocene when bison colonized …

Morphological Trait Evolution In Solanum (Solanaceae): Evolutionary Lability Of Key Taxonomic Characters, Rebecca Hilgenhof, Edeline Gagnon, Sandra Knapp, Xavier Aubriot, Eric Tepe, Lynn Bohs, Leandro Giacomin, Yuri Gouvea, Andres Orejuela, Christopher T. Martine, Clara Ines Orozco, Iris E. Peralta, Tina Sarkinen

Faculty Journal Articles

Solanum is one of the world's largest and economically most important plant genera, including 1245 currently accepted species and several major and minor crops (e.g., tomato, potato, brinjal eggplant, scarlet eggplant, Gboma eggplant, lulo, and pepino). Here we provide an overview of the evolution of 25 key morphological traits for the major and minor clades of this giant genus based on stochastic mapping using a well-sampled recently published phylogeny of Solanum. The most evolutionarily labile traits (showing >100 transitions across the genus) relate to plant structure (growth form and sympodial unit structure), herbivore defence (glandular trichomes), pollination (corolla shape …

Development Of A 16s Reference Library For Edna Metabarcoding The Freshwater Fishes Of Western Ecuador., Hannah M. Willis, Olivia G. Schweikart, Windsor E. Aguirre

DePaul Discoveries

This project examines the use of the 16S locus to amplify neotropical freshwater fishes native to Western Ecuador in a newly created 16S reference library for DNA barcoding and eDNA metabarcoding applications. Among the orders Characiformes, Siluriformes, Cichliformes, Gobiiformes, Cryprinodontiformes, Gymnotiformes, and Perciformes, a compendium of 105 specimens were sequenced, with 43 representing new 16S sequences previously unavailable on Genbank.

Fluidity And Inconstancy: Australian Bush Tomatoes As An Exemplar Of Non-Normative Sex Expression, Christopher T. Martine

Faculty Journal Articles

Solanum, a genus of ~1500 global species, is one of the more interesting plant groups in which to study reproductive biology and ecology. Overwhelmingly, species in this group express full cosexuality, where individual plants have flowers containing both fully-functioning “male” (staminate) and “female” (carpellate) organs. However, there have been multiple and widespread evolutionary transitions within the genus to non-normative variations on this ancestral condition. Australian bush tomatoes (ca. 40 species) are especially diverse in this regard, with uncommon variation and combinations of unisexuality and cosexuality -- including, most notably, two sexual systems known as dioecy (unisexual male or female …

Ethical Issues And Standards Of Responsible Research Conduct And Monitoring In An Adventist Institution Of Higher Learning - The Babcock Experience, Kayode O. Ogunwenmo, Godswill N. Anyasor, Grace O. Tayo

Adventist Human-Subject Researchers Association

Ethical issues and standards of responsible research conduct involving human participants are important considerations in any institution of higher learning and in particular Adventist institutions. Research conduct and ethics are reviewed and approved before they begin by the Babcock University Health Research Ethics Committee (BUHREC)

Past And Present Patterns Of Neutral And Adaptive Genetic Diversity In Wild Mandrills (Mandrillus Sphinx), Anna Weber

LSU New Orleans Theses and Dissertations

Although primates have fascinated researchers and the public alike for generations, one species that has remained enigmatic is the mandrill (Mandrillus sphinx), a large Cercopithecine monkey endemic to Central Africa. Mandrills are currently in decline due to bushmeat hunting, urbanization, and habitat loss. Neutral and adaptive genetic diversity are important tools for understanding evolutionary history and future viability, since diversity influences a species’ ability to adapt to a changing environment. However, thus far, minimal genetic information has been available for wild mandrills. Because of the dense vegetation in their tropical forest habitat, studying wild mandrills has proven to …

Vibroacoustic Response Of The Tympanic Membrane To Hyoid-Borne Sound Generated During Echolocation In Bats, Chelsie Snipes

Electronic Theses and Dissertations

The hyoid apparatus in laryngeally echolocating bats forms a mechanical connection between the larynx and auditory bullae and has been hypothesized to transfer the outgoing echolocation call to the middle ear during echolocation call emission. We used µCT data to build models of the hyoid apparatus and middle ear from six species of bats and used finite element modeling (FEM) to measure the vibroacoustic response of the tympanic membrane due to hyoid-borne sound generated during echolocation. We found that hyoid-borne sound in all six species stimulated the eardrum within a range likely heard by bats. Although there were minor differences …

Notes On Lung Development In South African Ghost Frogs (Anura: Heleophrynidae), Jackson R. Phillips, Jens Reissig, Gary Kyle Nicolau

Biology Student Research

Lungs are a prototypical trait of most tetrapods, but some amphibians have become secondarily lungless over evolutionary time. Anuran (frog) tadpoles offer an opportunity to examine lung loss from an evolutionary perspective, because there are many independent instances where lungs are not inflated until adulthood, and so are functionally lost. Lung loss is typically associated with living in fast-flowing streams, and so we examined larval lung development in the stream specialist family Heleophrynidae. We find that one genus, Hadromophryne Van Dijk, 2008, has large lungs as tadpole, while the other genus, Heleophryne Sclater, 1898, has much smaller, stunted lung buds. …

Does The Genome Of A Putatively Specialist Moth (Schinia Gracilenta) Contain A Signal Of The Indigenous Cultivation Of Its Host Plant (Iva Annua), Wren Renquist

2023 Midwest Ecology & Evolution Conference

When one species depends on one another for survival, they may have shared demographic histories. Further, when symbionts have shorter life spans, their rate of evolution may be quicker than that of their hosts. For this reason, detecting a recent demographic signal in a symbiont’s genome may often be easier than directly studying the host.

Here I study the slender flower moth (Schinia gracilenta) and its host plant, sumpweed (Iva annua). Sumpweed is thought to have been cultivated in North American ca. 5000 BC - AD 1700 and its range may have been expanded during this time. I collected S. …

Multilevel Selection On Social Network Traits Differs Between Sexes In Experimental Populations Of Forked Fungus Beetles, R. A. Costello, P. A. Cook, E. D. Brodie Iii, Vincent A. Formica

Biology Faculty Works

Both individual and group behavior can influence individual fitness, but multilevel selection is rarely quantified on social behaviors. Social networks provide a unique opportunity to study multilevel selection on social behaviors, as they describe complex social traits and patterns of interaction at both the individual and group levels. In this study, we used contextual analysis to measure the consequences of both individual network position and group network structure on individual fitness in experimental populations of forked fungus beetles (Bolitotherus cornutus) with two different resource distributions. We found that males with high individual connectivity (strength) and centrality (betweenness) had …

Proposing An Rna Interference (Rnai)-Based Treatment For Human Immunodeficiency Virus (Hiv) By Analyzing The Post-Transcriptional Gene Targeting Of Sars-Cov-2, Hepatitis C Virus, And A549 Lung Cancer Cells, Arjun Jagdeesh

UROP Posters

Human Immunodeficiency Virus (HIV) is a retrovirus that infects CD4+ T cell lymphocytes in humans, leading to the development of Acquired Immunodeficiency Syndrome (AIDS) if left untreated. While current treatment methods, including antiretroviral combination treatments, effectively limit HIV replication, HIV can evade these treatments due to its high mutation rate. Long-term antiretroviral treatment can also be toxic to patients, meaning patients would benefit from a new mechanism of HIV treatment. RNA interference (RNAi) is an antiviral pathway found in mammals, plants, and insects that involves a small-interfering RNA that is incorporated into a protein complex called the RNA-induced Silencing Complex …

Nuclear Phylogeny And Insights Into Whole-Genome Duplications And Reproductive Development Of Solanaceae Plants, Jie Wang, Weibin Xu, Junwen Zhai, Yi Hu, Jing Guo, Caifei Zhang, Yiyong Zhao, Lin Zhang, Christopher T. Martine, Hong Ma, Chien-Hsun Huang

Faculty Journal Articles

Solanaceae, the nightshade family, have ∼2700 species, including the important crops potato and tomato, ornamentals, and medicinal plants. Several sequenced Solanaceae genomes show evidence for whole-genome duplication (WGD), providing an excellent opportunity to investigate WGD and its impacts. Here, we generated 93 transcriptomes/genomes and combined them with 87 public datasets, for a total of 180 Solanaceae species representing all four subfamilies and 14 of 15 tribes. Nearly 1700 nuclear genes from these transcriptomic/genomic datasets were used to reconstruct a highly resolved Solanaceae phylogenetic tree with six major clades. The Solanaceae tree supports four previously recognized subfamilies (Goetzeioideae, Cestroideae, Nicotianoideae, …