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Articles 121 - 150 of 415

Full-Text Articles in Evolution

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

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

Dissertations

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

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


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

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

Dissertations and Theses

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


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

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

Undergraduate Research Symposium

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


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

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

Symposium of Student Scholars

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


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

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

Electronic Theses, Projects, and Dissertations

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


The Phylogeography And Molecular Systematics Of Woodrats (Genus: Neotoma) In The American Southwest, Katrina M. Derieg May 2021

The Phylogeography And Molecular Systematics Of Woodrats (Genus: Neotoma) In The American Southwest, Katrina M. Derieg

Biology ETDs

The American Southwest is a region where many biomes converge, harboring a wide variety of habitats ranging from desert to alpine environments. Habitat heterogeneity and the confluence of multiple species ranges make the American Southwest a biodiversity hotspot. Climate cycling throughout the Quaternary has driven the dynamics of changes in species’ ranges that are recorded by genetic signatures. For example, range expansion may lead to secondary contact between previously isolated populations or species. Contact can result in multiple evolutionary outcomes, including hybridization or the reinforcement and maintenance of independent lineages. I used multi-locus species tree methods to re-examine the nominal …


Strike-Induced Chemosensory Searching, Kleptoparasitism, And The Possibility Of Chemical Crypsis In Rattlesnakes, Mark Scott Teshera May 2021

Strike-Induced Chemosensory Searching, Kleptoparasitism, And The Possibility Of Chemical Crypsis In Rattlesnakes, Mark Scott Teshera

Open Access Theses & Dissertations

Predator-prey interactions shape the natural histories of both species as each tries to adapt and counter-adapt to the tactics of the other. This important evolutionary dynamic is crucial for ecosystem formation and stability. Predation is a fundamental aspect of life for most organisms, and many venomous reptiles, particularly ambush-foraging viperids, have evolved a prey-acquisition strategy that is highly effective in immobilizing prey, while minimizing possible counterattacks. Best studied in rattlesnakes, this remarkable behavioral sequence is known as strike-induced chemosensory searching (SICS). Throughout decades of research, the body of SICS literature on venomous reptiles has become fairly robust, particularly in rattlesnakes. …


A Spatially Explicit Model Of Stabilizing Selection For Improving Phylogenetic Inference, Jeremy M. Beaulieu, Brian C. O'Meara, Michael A. Gilchrist Apr 2021

A Spatially Explicit Model Of Stabilizing Selection For Improving Phylogenetic Inference, Jeremy M. Beaulieu, Brian C. O'Meara, Michael A. Gilchrist

Biological Sciences Faculty Publications and Presentations

Ultraconserved elements (UCEs) are stretches of hundreds of nucleotides with highly conserved cores flanked by variable regions. Although the selective forces responsible for the preservation of UCEs are unknown, they are nonetheless believed to contain phylogenetically meaningful information from deep to shallow divergence events. Phylogenetic applications of UCEs assume the same degree of rate heterogeneity applies across the entire locus, including variable flanking regions. We present a Wright-Fisher model of selection on nucleotides (SeION) which includes the effects of mutation, drift, and spatially varying, stabilizing selection for an optimal nucleotide sequence. The SeION model assumes the strength of stabilizing selection …


The Distribution In Native Populations From Mexico And Central America Of The C677t Variant In The Mthfr Gene, Lucio A. Reyes Mar 2021

The Distribution In Native Populations From Mexico And Central America Of The C677t Variant In The Mthfr Gene, Lucio A. Reyes

USF Tampa Graduate Theses and Dissertations

Objectives: To explore evolutionary hypotheses for the high frequencies of a substitution in the methylenetetrahydrofolate reductase (MTHFR) gene, in Mexican and Central American Indigenous populations.

Materials and methods: We obtained allele frequencies for the C677T variant in the MTHFR gene and ecological information for 37 indigenous samples from Mexico and Central America. We calculated Hardy–Weinberg equilibrium and computed Fst statistics. We computed correlations between the samples' allele frequencies and ecological and geochemical variables.

Results: Many of the samples have extremely high frequencies of the T allele (q̄ = 0.62, median = 0.66). In this region, the frequency of the T …


Male Competition Reverses Female Preference For Male Chemical Cues, Z. Vilella-Pacheco, L. D. Mitchem, Vincent A. Formica, E. D. Brodie Iii Mar 2021

Male Competition Reverses Female Preference For Male Chemical Cues, Z. Vilella-Pacheco, L. D. Mitchem, Vincent A. Formica, E. D. Brodie Iii

Biology Faculty Works

Females must choose among potential mates with different phenotypes in a variety of social contexts. Many male traits are inherent and unchanging, but others are labile to social context. Competition, for example, can cause physiological changes that reflect recent wins and losses that fluctuate throughout time. We may expect females to respond differently to males depending on the outcome of their most recent fight. In Bolitotherus cornutus (forked fungus beetles), males compete for access to females, but copulation requires female cooperation. In this study, we use behavioral trials to determine whether females use chemical cues to differentiate between males and …


Using Audio Recording Devices And Multiseason Occupancy Modelling To Evaluate Clark's Nutcracker (Nucifraga Columbiana) Occurrence In Whitebark Pine Habitats Of Washington's Cascade Mountains, Lauren Taracka Jan 2021

Using Audio Recording Devices And Multiseason Occupancy Modelling To Evaluate Clark's Nutcracker (Nucifraga Columbiana) Occurrence In Whitebark Pine Habitats Of Washington's Cascade Mountains, Lauren Taracka

Undergraduate Honors Theses

The Clark’s nutcracker (Nucifraga columbiana) and whitebark pine (Pinus albicaulis), both native to the harsh subalpine habitats of Washington’s Cascade Mountains, are being negatively impacted by white pine blister rust (Cronartium ribicola), the mountain pine beetle (Dendroctonus ponderosae), and climate change. As temperatures continue to warm, while many species at lower elevations can move upward in elevation to suit their temperature needs, subalpine species do not have that option. Whitebark pine is a keystone tree species - numerous animals consume its high fat, high energy seeds; it’s a nurse tree, providing shelter …


Lynn Margulis And Boris Kozo-Polyansky: How The Symbiogenesis Was Translated From Russian, Victor Fet Jan 2021

Lynn Margulis And Boris Kozo-Polyansky: How The Symbiogenesis Was Translated From Russian, Victor Fet

Biological Sciences Faculty Research

This contribution details the complex history of the early work by Boris Kozo-Polyansky (1924) that became available in English translation 86 years after it was published in Russian. The great American naturalist Lynn Margulis—whose serial endosymbiosis theory was presciently predated by Kozo-Polyansky by four decades—was instrumental in organizing this resurrection and ‘horizontal transfer’ of knowledge, forgotten by that time even in Russia.


Lepidopteran Granivory Reduces Seed Counts In A Rare Species Of Riparian Scour Prairies, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine Jan 2021

Lepidopteran Granivory Reduces Seed Counts In A Rare Species Of Riparian Scour Prairies, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine

Faculty Journal Articles

In Pennsylvania Baptisia australis var. australis is found along only four waterways: the Allegheny River, Youghiogheny River, Clarion River, and Red Bank Creek. Because of its limited distribution and small number of extant populations, the species is considered state-threatened in Pennsylvania. In addition, the riparian prairie habitat that Pennsylvania Baptisia australis var. australis is restricted to is also in decline and considered vulnerable. Because of these conservation concerns, insights into the natural history of the taxon in the state is valuable and will inform conservation efforts. Field surveys and fruit collections along the Allegheny River and herbarium collections were used …


Initial And Advanced Stages Of Microbiota Establishment Within The Tsetse Fly, Miguel Eduardo Medina Munoz Jan 2021

Initial And Advanced Stages Of Microbiota Establishment Within The Tsetse Fly, Miguel Eduardo Medina Munoz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Symbiosis is a long-term physical association between two or more species, although little is known regarding its evolutionary origins, particularly at the genetic level. Tsetse flies are the vector of African trypanosomes, causative agents of Human and Animal African Trypanosomiases. Tsetse provide an ideal model for studying initial and advanced stages of symbiosis. Tsetse have a simple digestive tract microbiota primarily consisting of two bacteria; the ancient mutualist Wigglesworthia glossinidia and the recently acquired Sodalis glossinidius. This work presents a chronological study in evolutionary terms of the history of a microbial-insect association. First, I present concepts on symbiosis and …


The Evolution Of Technology, Kelly Cooper Jan 2021

The Evolution Of Technology, Kelly Cooper

Williams Honors College, Honors Research Projects

As per outlined by Dr. Quinn, this literature review will be a comprehensive review paper including an overview of current and previous research done in the field of Memetics. This will further include sifting through literature to hone in on a specific, new area of memetics Dr. Weeks is focused on, the evolutionary change of abiotic factors through purchasing. This is to be completed with the help of the library worshops designed to teach the skills necessary to undergo a literature review of this size. I will also participate in weekly reading groups to discuss papers and work closely with …


Functional Genetic Approaches To Provide Evidence For The Role Of Toolkit Genes In The Evolution Of Complex Color Patterns In Drosophila Guttifera, Mujeeb Olushola Shittu Jan 2021

Functional Genetic Approaches To Provide Evidence For The Role Of Toolkit Genes In The Evolution Of Complex Color Patterns In Drosophila Guttifera, Mujeeb Olushola Shittu

Dissertations, Master's Theses and Master's Reports

Toolkit genes are set of genes that orchestrate the development of basic body plan of animals, and they are highly conserved in all animals. The co-option of the toolkit genes into the pigmentation pathway has led to the evolution of novel species. This study focuses on understanding how the complex color patterns in animals develop by using the Drosophila species in the quinaria group as models. We developed an mRNA in situ hybridization (ISH) protocol, which allowed us to study gene expression patterns in the abdomen of developing pupae of non-model Drosophila species (Chapter 2). Through ISH, we found that …


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 …


Influence Of Testosterone On Male-Male Competition In The Red-Sided Garter Snake, Thamnophis Sirtalis Parietalis, Isabella M. G. Bukovich Dec 2020

Influence Of Testosterone On Male-Male Competition In The Red-Sided Garter Snake, Thamnophis Sirtalis Parietalis, Isabella M. G. Bukovich

Senior Honors Projects, 2020-current

Female mimicry in the red-sided garter snake, Thamnophis sirtalis parietalis, is described in several well-studied evolutionary advantages, but an aspect that remains elusive is how reproductive traits are linked to the 3-fold higher circulating androgens in males with this phenotype. In this study, we implanted male garter snakes (n=15 per group) with either a blank implant (SHAM; control) or a T implant, the latter simulating the female mimic phenotype. Following simulated low-temperature dormancy, males were scored for courtship intensity over three days of behavioral trials with females housed in the same facility. Males were sacrificed, and sperm were collected …


Introduction To Neutrosophic Genetics, Florentin Smarandache Dec 2020

Introduction To Neutrosophic Genetics, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Neutrosophic Genetics is the study of genetics using neutrosophic logic, set, probability, statistics, measure and other neutrosophic tools and procedures. In this paper, based on the Neutrosophic Theory of Evolution (that includes degrees of Evolution, Neutrality (or Indeterminacy), and Involution) – as extension of Darwin’s Theory of Evolution, we show the applicability of neutrosophy in genetics, and we present within the frame of neutrosophic genetics the following concepts: neutrosophic mutation, neutrosophic speciation, and neutrosophic coevolution.


Cross-Host Correlations And Multivariate Effects Of Herbivore Specialization, Daniel J. Zydek Nov 2020

Cross-Host Correlations And Multivariate Effects Of Herbivore Specialization, Daniel J. Zydek

USF Tampa Graduate Theses and Dissertations

The distribution of insect herbivores among plant hosts is largely nonrandom: most herbivores have limited sets of hosts within one or a few plant families. This host use specialization is reinforced by traits that confer differential fitness across host plant species. Classic explanations for herbivore specialization predict that evolutionary trade-offs reinforce these relationships by imposing costs in the form of reduced potential fitness on alternative hosts, due to negative genetic correlations in fitness across hosts. This prediction that trade-offs constrain host use in herbivores can be tested with experimental evolution, by showing the direct evolutionary effects of host manipulation on …


Quantifying Structure And Variation In Complex Phylogenetic Data, Genevieve Geraldine Mount Nov 2020

Quantifying Structure And Variation In Complex Phylogenetic Data, Genevieve Geraldine Mount

LSU Doctoral Dissertations

Identifying the source and structure of variation in nature is crucial to understanding fundamental aspects of evolution. Despite a recent plethora of genetic and morphological data, many interesting questions about the relationships between different groups remain unresolved. My dissertation evaluates three approaches for identifying and quantifying the variation within phylogenetic datasets. Characterizing variation within datasets and across analytical methods gives insight into biologically interesting characters, unusual evolutionary processes, and areas for model improvement.

Network-based community detection approaches offer a powerful tool to describe variation in phylogenetic signal across the genome (i.e., gene tree variation). In Chapter 2, I investigate the …


Alfred Russel Wallace Notes 12: How Good Was Wallace's Memory?, Charles H. Smith Nov 2020

Alfred Russel Wallace Notes 12: How Good Was Wallace's Memory?, Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (1823−1913) continues to be criticized for inconsistencies in his recollections of the earlier events in his life. This criticism, while not entirely unjust, has nevertheless been overplayed. Critics have not attended to the general understanding that self-biography is under the influence of two aspects of memory: that pertaining to remembrance of the qualities of past situations, and a secondary ability to assign absolutes of name or date to such memories. All evidence suggests that Wallace’s memory in the first sense was excellent throughout his life, but that he was prone to lapses of the second type.


Structure And Evolution Of Lizard Immunity Genes, Trent Santonastaso Aug 2020

Structure And Evolution Of Lizard Immunity Genes, Trent Santonastaso

LSU New Orleans Theses and Dissertations

One of the most important gene families to play a role in adaptive immunity is the major histocompatibility complex (MHC). MHC class II loci are considered to be the most variable loci in the vertebrate genome, and studies have shown that this variability can be maintained through complex co-evolutionary dynamics between host and parasite. Despite the rich body of research into the MHC, there is comparatively little understanding of its genomic architecture in reptiles. Similarly, loci associated with innate immunity have received little attention in reptiles compared to other vertebrates. In the first chapter, we investigated the structure and organization …


Hind Wing Eyespots Of Brassolini Butterflies (Lepidoptera, Nymphalidae): Evolutionary Diversification And Functions In Anti-Predator Defense And Mating Behavior, Logan Crees Aug 2020

Hind Wing Eyespots Of Brassolini Butterflies (Lepidoptera, Nymphalidae): Evolutionary Diversification And Functions In Anti-Predator Defense And Mating Behavior, Logan Crees

LSU New Orleans Theses and Dissertations

Ventral hind wing eyespots are prominent pattern elements in Brassolini butterflies, likely functioning in predator-prey interactions and reproductive activities. Caligo and Opsiphanes differ in male mate-seeking behaviors and it has been suggested that Caligo females use the male cua1 eyespot as a mate-locating cue, but Opsiphanes females do not seem to do so. We predict Caligo males should have larger eyespots than congeneric females, but the sexes would not differ in eyespot size in Opsiphanes. Our analyses supported both these predictions. Displacing the eyespot to the center of the wing makes eyespots more conspicuous, we asked if eyespot position …


Macronutrient Intake And Simulated Infection Threat Independently Affect Life History Traits Of Male Decorated Crickets, Kristin Duffield, Kylie J. Hampton, James Rapkin, John Hunt, Scott K. Sakaluk, Ben M. Sadd, Thomas M. Houslay Jun 2020

Macronutrient Intake And Simulated Infection Threat Independently Affect Life History Traits Of Male Decorated Crickets, Kristin Duffield, Kylie J. Hampton, James Rapkin, John Hunt, Scott K. Sakaluk, Ben M. Sadd, Thomas M. Houslay

Faculty Publications – Biological Sciences

Nutritional geometry has advanced our understanding of how macronutrients (e.g.,proteins and carbohydrates) influence the expression of life history traits and theircorresponding trade-offs. For example, recent work has revealed that reproduc-tion and immune function in male decorated crickets are optimized at very differentprotein:carbohydrate (P:C) dietary ratios. However, it is unclear how an individual'smacronutrient intake interacts with its perceived infection status to determine in-vestment in reproduction or other key life history traits. Here, we employed a fullyfactorial design in which calling effort and immune function were quantified formale crickets fed either diets previously demonstrated to maximize calling effort(P:C = 1:8) or immune …


Species Dispersal Modes In Amphitropical Plant Species Of North And South America, Samera Lemma Mulatu May 2020

Species Dispersal Modes In Amphitropical Plant Species Of North And South America, Samera Lemma Mulatu

Honors College Theses

Amphitropical disjunct plants are species that occur in both North and South America but not in the intermediate equatorial region. How amphitropical species dispersed across the Americas to their current distribution remains uncertain. To explain amphitropical distributions, three hypotheses were developed to test that (1) species dispersed successively through island hopping across the tropical zone in temperate microhabitats (= stepping stones), (2) species came to their current distribution through vicariance, or (3) species dispersed by a single long distance dispersal event. Twenty-five species were studied to infer their historical distributions with species distribution models in MaxEnt. Distribution models for each …


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 ( …


Earliest Known Material Of Amia, Bowfin, From The Sentinel Butte Formation (Paleocene), Medora, North Dakota, Abby Grace Moore May 2020

Earliest Known Material Of Amia, Bowfin, From The Sentinel Butte Formation (Paleocene), Medora, North Dakota, Abby Grace Moore

Theses and Dissertations

Amia calva is an icon in the field of comparative osteology, yet we have a poor understanding of the evolution of the genus because many fossil amiid bones have gone unidentified. Here we identify new material of the genus, Amia, with evidence of two unidentified species. Previously, the oldest known material identifiable as Amia cf. A. pattersoni, was a specimen from the Paleocene epoch of Alberta, Canada approximately 58 million years in age. Fossils of the two unidentified species of Amia were found in the Sentinel Butte Formation, a geologic formation of Paleocene age (~ 60 million years …


Evolutionary Ecology Of Host-Parasite Relationships: Role Of Host Ecology, Phylogeny, And Demographics In Shaping Parasite Evolution, Erika Taylor Gendron Apr 2020

Evolutionary Ecology Of Host-Parasite Relationships: Role Of Host Ecology, Phylogeny, And Demographics In Shaping Parasite Evolution, Erika Taylor Gendron

Biology ETDs

Host-parasite systems exist across complex and ecologically heterogeneous landscapes, and may occur across taxonomically and ecologically disparate host species. Under these conditions, mechanisms underlying microevolutionary processes (i.e. gene flow, genetic drift) are not always clear, and may be mediated by numerous co-occurring factors specific to individual hosts. Host traits such as host immunology, demographics, phylogeny and ecology may act in concert to shape host-parasite relationships, and ultimately evolutionary processes. The research described herein used phylogeographic, phylogenomic, and population genetic methods to further understanding of how host traits impact the evolutionary ecology of trematode systems, using avian schistosomes (Digenea: Schistosomatidae) as …