Ecology and Evolutionary Biology Commons^™

Toward Improved Global Food Security: Uncovering How Tomatoes Fight Root-Knot Nematodes, Chingyan H. Huang

The Journal of Purdue Undergraduate Research

No abstract provided.

Exploring The Evolution Of Callose Synthase In Green Plants, Giovanna Durante

The Journal of Purdue Undergraduate Research

No abstract provided.

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 …

A Survey Of Proximal Sensilla Associated With Denticle Subrows On Scorpion Pedipalp Fingers (Arachnida: Scorpiones), With Observations On Scorpion Fluorescence, Graeme Lowe, Victor Fet

Euscorpius

Sensilla on the dentate margins of scorpion pedipalp fingers, associated with denticle subrows or terminal denticles, were surveyed by white light, UV fluorescence and scanning electron microscopy. A total of 163 species belonging to 103 genera from 19 families were examined, representing all major phylogenetic lineages in the order. In the majority of species (141/152) with dentition organized into linear subrows of median denticles, a small socketed sensillum with a short shaft was observed at the proximal terminus of each subrow, termed a ‘subrow proximal sensilla’ (SPS). With few exceptions, SPS were non-fluorescent (‘Type N’) in buthids, and fluorescent (‘Type …

Factors That Influence Small Mammal Long Bone Morphology: An Analysis Of The Femora, Tibiae, And Humeri Of The Eastern Gray Squirrel (Sciurus Carolinensis), Tyler Everette Blake

Theses, Dissertations and Capstones

The goal of this study is to examine the effect of urbanization and latitude on bone morphology, specifically limb length and bone density among gray squirrels endemic to the eastern United States. This study’s hypotheses are as follows: gray squirrels occupying lower latitudes will have larger body sizes and longer limbs relative to body size than those at higher latitudes following Bergmann’s and Allen’s rules. Further, squirrels in urban habitats will have greater bone density than those in rural habitats. Results show moderate correlation between body mass and respective proxies and latitude following Bergmann’s rule. Weak correlations were found between …

Individuality Matters But Its Cause Has Consequences, Daniel T. Blumstein

Animal Sentience

I discuss the relationship between individuality and heritability and note that the mechanism driving individual differences matters for conservation and management outcomes.

An Exploration Of Factors Influencing Emerging Adults’ Decision-Making Regarding Family Intentionality, Samantha Mckee

Graduate Research Theses & Dissertations

The purpose of this mixed methods study was to gain an understanding of factors that may influence emerging adults’ decision-making regarding family intentionality. Specifically, it aimed to answer two research questions: 1) What factors influence an emerging adults’ decision-making regarding family intentionality? 2) Is there a correlation between the number of Adverse Childhood Experiences (ACEs) an individual has experienced and their desire to have children? This study also examined how ACEs are factored into the different systems of Bronfenbrenner’s Ecological Systems Theory and how they affect the child at each level. This study utilized a sequential quan-->QUAL design, combining …

Paralog Switching Facilitates Diadromy: Ontogenetic, Microevolutionary And Macroevolutionary Evidence, Rebecca S. Colby, Stephen D. Mccormick, Jonathan P. Velotta, Elizabeth Jockusch, Eric T. Schultz

EEB Articles

Euryhalinity is present in diverse aquatic taxa and requires flexible osmoregulation to field the challenges posed by differing salinities. Na+, K+-ATPase (NKA) is a ubiquitous ion pump in the gills of fishes and, for some species, paralogs of the catalytic -subunit (NKA 1a and NKA 1b) exhibit reciprocal expression between fresh- and seawater, termed paralog-switching. We investigated the expression and evolution of NKA paralogs in Alewife (Alosa pseudoharengus), a euryhaline and migratory fish. Comparisons between landlocked and diadromous life history forms and migrant and pre-migrant ontogenetic stages were used to study shifts in NKA paralog expression related to freshwater or …

Understanding The Origin Of Parthenogenesis Via Crossing And Crispr Gene Editing In Daphnia Pulex, Thinh Pham

Biology Dissertations - Archive

Daphnia has been used as a key model system for studying ecological changes, evolution, and genomics for the past few decades due to its rapid turnover time in reproduction. The organism possesses two fascinating modes of reproduction: obligate parthenogenesis and cyclical parthenogenesis. This dissertation delves into the intricate reproductive strategies of Daphnia pulex, focusing on hybrid F1s from different reproductive modes. The first aim is to investigate 31 hybrid F1s generated from obligate parthenogenesis (OP) and cyclical parthenogenesis (CP) parental lines. Transcriptomic analysis reveals misexpression patterns and regulatory divergences, highlighting meiosis-related genes like CDC6 as potential parthenogenesis regulators. The …

Exploring Ecological Drivers Of Evolution Of The Brain, Cognition, And Behavior, Meghan Korte

Biology Dissertations - Archive

Evolutionary theory proposes that increases in brain size confer cognitive and behavioral benefits that offset the expensive investment in brain tissue. However, few studies have examined the relationship between brain size, cognition, and behavior within species. The majority of research has focused on cross-species comparisons, thus there is a need for empirical research within species examining how contrasting ecological pressures select for cognitive and behavioral benefits and how these may evolve in tandem with changes in brain size. My dissertation addresses this gap by examining: 1) Whether selection on brain size is linked to improvements in cognitive ability; 2) How …

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. …

Robust Phylogenetic Regression, Richard Adams, Zoe Cain, Raquel Assis, Michael Degiorgio

Entomology and Plant Pathology Faculty Publications and Presentations

Modern comparative biology owes much to phylogenetic regression. At its conception, this technique sparked a revolution that armed biologists with phylogenetic comparative methods (PCMs) for disentangling evolutionary correlations from those arising from hierarchical phylogenetic relationships. Over the past few decades, the phylogenetic regression framework has become a paradigm of modern comparative biology that has been widely embraced as a remedy for shared ancestry. However, recent evidence has shown doubt over the efficacy of phylogenetic regression, and PCMs more generally, with the suggestion that many of these methods fail to provide an adequate defense against unreplicated evolution—the primary justification for using …

Data From: Phylogenomic Species Delimitation Of Studfishes (Fundulidae: Fundulus): Evidence For Cryptic Species In Agreement With The Central Highlands Vicariance Hypothesis, Kayla M. Fast, Peter J. Hundt, Zachariah D. Alley, Michael W. Sandel

CFR Publications

The Central Highlands ecoregion of the eastern United States represents a hotspot of freshwater biodiversity, with replicated patterns of vicariant speciation east and west of the Mississippi River. Previous phylogeographic investigation of the studfishes (Fundulus subgenus Fundulus) revealed evidence for vicariant speciation in the Central Highlands, but data were limited to a small number of gene sequences generated with Sanger sequencing. We used double digest restriction-site associated DNA sequencing (ddRADseq) to improve resolution of phylogeographic patterns and better characterize population genetic variation. Our sample design included individuals from the Fundulus catenatus species group (F. catenatus, F. bifax, …

Bibliography, Charles H. Smith

Faculty/Staff Personal Papers

Bibliography of publications by Charles H. Smith.

Donald Griffin: A Visionary In Science And Consciousness, Charles Foster

Animal Sentience

Carolyn Ristau’s (2024) timely biography reviews Donald Griffin’s pioneering ideas with depth and historical perspective, describing Griffin’s approach to science, his openness to interdisciplinary insights, and his bold stance on consciousness. Ristau’s work highlights Griffin’s relevance to contemporary debates on consciousness and natural selection.

Characterizing New Plant Fossils With Woody Growth From The Battery Point Formation Of Quebec (Canada), Emma T. Casselman

Cal Poly Humboldt theses and projects

The oldest woody growth has been recognized in several Early Devonian (ca. 410-395 Ma) euphyllophytes. Their taxonomic diversity is difficult to evaluate due to a lack of quantitative methods for comparing plants based on secondary xylem anatomy. In turn, this hinders understanding of their implications for the evolution of plant development. To develop metrics that quantify secondary xylem anatomy and allow for conclusive comparisons, I investigated extant taxa and Early Devonian fossil woody taxa. I developed multiple metrics for quantifying tracheid size as a function of position in the secondary xylem and tested them on a dataset of extant gymnosperms. …

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 …

A Balancing Act: Microrna Mediated Insect-Bacterial Homeostasis And The Tsetse Fly, Mason Hubbard Lee

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microbial symbioses are ubiquitous across all kingdoms of life with broad and diverse impacts on the evolution of species. The sum of all microbes living in, on, or otherwise in close association with a host form the microbiota. In some cases, the development of a stable microbial association seems to have been necessary for the specialization of diet, as can be observed in numerous insect species, especially wood-eating, sap-feeding, and blood-feeding organisms. For the medically and economically tsetse fly (family Glossinidae), the mutualistic bacteria Wigglesworthia glossinidia is required for proper reproduction and supplementation of nutrients that the fly does not …

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 …

The Genetic Basis Of Two Reproductive Traits In Monkeyflowers: Stigma Closure And Corolla Carotenoids, Rachel Anne Halperin

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Abstract

The interactions between pollinators and flowers have long been a driving force for the evolution of many physical floral traits. Traits such as flower shape, size, color, and smell are just some of these traits that evolve because of these interactions. This evolution does not only occur in the more obvious morphological floral traits, however, but also in more subtle traits like touch sensitive stigma closure. In hundreds of Lamiales species, the bilobed stigma, the organ that receives pollen from pollinators, closes rapidly upon touch. Theory and experiments show that this novel dynamic reproductive trait increases pollen export and …

Co-Divergence Of Lemur Hosts And Gut Microbiomes Across Multiple Evolutionary Scales, Mariah E. Donohue

Theses and Dissertations--Biology

This dissertation bridges micro- and macroevolutionary approaches to understand the co-diversification of animal hosts and their gut microbiomes at different evolutionary timescales. I examined these dynamics using wild lemurs, a diverse Primate clade endemic to the island of Madagascar.

First, I tested the relative effects of host phylogenetic relationships, diet, and habitat in shaping the gut microbiome through deep evolutionary time and across distinct microbial kingdoms. I designed a natural experiment sampling feces from rainforest and dry forest lemur communities with similar phylogenetic assemblages and considerable variation in dietary strategy. Then, I amplified and sequenced two metabarcoding genes, the V4 …

The Evolution Of The Metazoan Circadian Molecular Mechanism And The Conservation Of Canonical Circadian Elements, Olivia Waldridge

Theses and Dissertations--Biology

The temporal organization of biological activities through circadian rhythms is pivotal for the survival of organisms. Significant progress has been made in understanding the molecular foundations of animal circadian clocks through the characterization of key components such as Clock, Bmal1/Cycle(Cyc), Period (Per), Timeless, and Cryptochrome (Cry) in several model organisms. To determine the universality of this conservation, we investigated the sequences of these genes and their paralogs across 46 animal species that encompass multiple phyla in the metazoan kingdom to resolve the relative timing of duplication and loss events that have diversified core clock components in the metazoan kingdom. Using …

Reproductive Isolation And Gene Flow Across Space, Time And Genomes In Neodiprion Lecontei And N. Pinetum, Ashleigh Nicole Glover

Theses and Dissertations--Biology

To explain biodiversity, evolutionary biologists must understand how independent lineages arise via the evolution of reproductive isolation during the speciation process. Hybridizing taxa provide an excellent opportunity to investigate the evolution of reproductive isolating barriers and genomic divergence, thereby enhancing our understanding of speciation. However, hybridization between diverging taxa can vary across geographic space, the genome, and time. Thus, understanding the factors that promote or inhibit hybridization can provide insight into the biotic, environmental, and genetic causes of divergence and gene flow. Importantly, the mechanisms responsible for generating variation in hybridization dynamics and the consequences of such hybridization remains unknown …

Hunting Types In North American Eocene And Oligocene Carnivores And Implications For Nimravid Extinction, Miguel Andres Castellanos

Graduate Research Theses & Dissertations

The late Eocene and Oligocene is traditionally seen as a time of great climactic shift, with open habitats beginning to appear and forests receding. This time period saw both the diversification and subsequent extinction of North American nimravids. The causes of the extinction of this early sabertooth group in the Arikareean remain unclear. One possibility for their decline is that nimravids were competitively disadvantaged in open habitats relative to contemporary, possibly more cursorial caniform predators. Here I analyze and compare the hunting styles of Eocene and Oligocene predators in correlation with their ecological implications via discriminant function analysis of the …

Alfred Russel Wallace Notes 29. Extraterrestrial Entertainment: Are We Being Monitored By Alien Beings?, Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (1823−1913) was an early advocate for the rational assessment of likelihood of extraterrestrial life. Current efforts to evaluate the situation have ranged from the heavily self-indulgent to the more objective, and it is still often difficult to decide just how much of the information we are receiving on the subject is dependable. An attempt is made here to cut through the haze and reduce the matter to elementals.

Social Interactions And Spatial Structure Drive Community Assembly Of Bacterial Biofilm, Matthew C. Bond

Dartmouth College Ph.D Dissertations

Despite the critical nature which microbial communities play in the natural world and human civilization, the breadth of understanding remains shallow. Challenged by scale, high variability between environments, and extensive diversity, microbial ecologists strive to understand connections between a community’s structure and function, as well as the ecological and evolutionary mechanisms underlying observed natural patterning of communities. Biofilms are the predominate mode of growth for microbial communities—characterized by cellular attachment to a surface via a self-produced matrix and heterogeneous structure, often resulting in a primary growth front along the biofilm surface due to differential access to bulk nutrients (cite). This …

Can Edna Be Used To Locate Shawnee Hills Cavefish Forbesichthys Papilliferus?, Megan Brandt, Timothy Spier Phd, Gary Zeruth Phd

Murray State Theses and Dissertations

Traditional stream fish sampling methods, such as seining and electrofishing, are time consuming, expensive, and limited to short stretches of stream. However, the analysis of environmental DNA (eDNA) from water samples promises to be a quick, inexpensive method for detecting fish. The streams of the Land Between the Lakes Recreational Area (LBL) are unique, undisturbed streams which contain many interesting fish species for which little information exists. One such rare species is the Shawnee Hills Cavefish Forbesichthys papilliferus, which is known to exist in a few LBL streams. However, the complete distribution of the Shawnee Hills Cavefish in LBL …

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 …

A Multimolecular Perspective On The Success Of Wolf Recovery And Relocation, Samuel D. Hervey

Dissertations, Master's Theses and Master's Reports

With global biodiversity in decline and many species isolated in fragmented habitats, conservation efforts increasingly rely on natural recolonization and translocation to restore ecosystems. These strategies face challenges such as genetic erosion and habitat limitations, highlighting the need for effective monitoring practices. This research assesses the success of wolf recovery initiatives by examining long-term genetic and genomic health using both traditional and advanced molecular methods. First, we investigated the genetic health of 19 gray wolves (Canis lupus) relocated to Isle Royale National Park to restore ecosystem balance. Initial genetic assessments with microsatellites found that these wolves had genetic diversity metrics …