Ecology and Evolutionary Biology Commons^™

Reproductive Characteristics Of The Stripetail Darter (Etheostoma Kennicotti) Relative To Monogenean Gill Parasite Infection In Estill Fork In North Alabama, Joy L. Garcia, Zeina Celine Sleiman, Corinne N. Preacher, Bruce Stallsmith

Southeastern Fishes Council Proceedings

What relationship exists between Aethycteron sp. gill parasite infection and the reproductive characteristics of stripetail darters, Etheostoma kennicotti? 450 E. kennicotti were collected over 11 months from Estill Fork in Jackson County, Alabama. Gonads were removed and photographed. All oocytes were counted and then classified into one of four developmental stages based on size and appearance. Gill parasites belonging to the monogenean genus Aethycteron were excised, photographed, and counted. Sexual dimorphism in length and mass was observed in E. kennicotti. The number of males found at the 25> mm SL range far outnumbered the females while almost all …

A Comparison Of Seasonal Reproductive Pattern In Two Sympatric Darters Of The Simoperca Clade, Etheostoma Duryi And Etheostoma Simoterum, Tiffany Bell, Elizabeth Cantrell, Bruce Stallsmith

Southeastern Fishes Council Proceedings

We present results from an examination of the seasonal reproductive patterns of two closely related sympatric darter species of the Simoperca clade, Etheostoma duryi and Etheostoma simoterum. Most members of the genus Etheostoma exhibit striking sexual dimorphism, making reproductive strategy a logical point of study. Monthly collections of specimens over a one-year period were performed at a single site on the Flint River near Huntsville, Alabama. Standard length and gross somatic mass were measured for all individuals. Sex ratio was examined for possible skew. Measures of reproductive effort were monthly means of gonadosomatic index of both sexes, total oocyte count, …

Sphenoidal Sinuses And Spherical Harmonics: Variation And Covariation Of The Most Morphologically Diverse And Least Understood Paranasal Sinus, Katharine Grace Josephine Ryan

Doctoral Dissertations

Understanding the shape variation of the human sphenoidal sinus is important to several areas of research. This includes clinical investigation (sinus pathology and safe endoscopic endonasal surgical practice) and paranasal sinus evolution (for which there is still no consensus). Yet, the sphenoidal sinus has high morphological variation, prohibiting its quantification through traditional geometric morphometric landmarking methods. The sphenoid body, and thus also the sinus contained within, is located directly at the developmental center of the basicranium in humans, where the three cranial fossae meet at the midline, and adjacent to the three synchondroses which are the sites of cranial base …

Climate-Driven Selection Results In Powerful Geographic Framework For Predicting Phenotype, Alexandra Neild

Masters Theses

Our ability to prepare for and mitigate the likely ecological and evolutionary impacts of climate change largely depends upon our ability to predict the phenotypic responses of organisms that allow them to persist, adapt, and migrate along environmental stress gradients. Using fifteen populations of cottonwoods, a dominant riparian forest tree, that are distributed along elevation gradients and represent three genetic provenances, we hypothesized and show that: 1) populations within a provenance demonstrate parallel evolutionary responses to climatic gradients associated with elevation; and 2) the evolutionary effects of elevation on bud-break phenology varied by provenance. Across all populations, we find strong …

Microplastics Exposure In At-Risk Myotis Lucifugus Bats Of The Northeastern United States, Leah Crowley

Chancellor’s Honors Program Projects

No abstract provided.

A Systematic And Biogeographic Study Of Trillium (Melanthiaceae), Jayne A. Lampley

Doctoral Dissertations

Trillium (Melanthiaceae, Parideae) has a disjunct distribution occurring in eastern and western North America, and eastern Asia. Past studies have examined the phylogeny and historical biogeography of Melanthiaceae and Parideae, however these studies either did not fully examine these aspects within Trillium or did not employ sufficiently broad taxonomic or character sampling to clarify relationships among taxa. The first phylogenetic analysis presented in this study provides a resolved phylogeny for Trillium s.l. and Paris s.l. by using a dataset of 70 plastid coding genes and by sampling broadly from Trillium s.s., Pseudotrillium, Trillidium, Paris s.s., Daiswa, and Kinugasa. The results …

Impacts Of Anthropogenic Change On Plant Reproduction And Fitness, Alexandra S. Faidiga

Masters Theses

Humans are altering natural systems around the globe in myriad ways. For plant species, such anthropogenic changes have resulted in increasingly fragmented populations, desynchronized interactions with mutualists, and shifted geographic ranges, among other effects. However, despite numerous examples of human impacts on plant populations, the consequences of these changes on plant reproduction remain poorly understood. In my thesis, I investigate the impacts of two forms of anthropogenic change–habitat disturbance and climate warming–on plant reproduction and fitness. I take two distinct approaches to address questions posed at local and regional scales. In Chapter I, I ask how inbreeding depression varies across …

Evolution And Resurrection Ecology Of A Foundational Coastal Marsh Plant, Jennifer L. Summers

Doctoral Dissertations

Stratified storage of dormant seeds in soil can result in natural archives useful for studying evolutionary responses to environmental change. However, few studies leverage soil-stored seed banks as natural archives, in part because of concerns over attrition, bias, and sediment mixing. Here, I examine the persistent seed bank of Schoenoplectus americanus, a foundational brackish marsh sedge, to a) determine whether it can serve as a resource for reconstructing demographic and population genetic/genomic variation, b) whether and how evolution may be occurring across a century. After extracting seeds from radionuclide-dated soil cores taken across the Chesapeake Bay, I “resurrected” age …

Morphological And Gene Expression Plasticity In Neotropical Cichlid Fishes, Sharon Fern Clemmensen

Doctoral Dissertations

Trophic divergence in cichlid fish is linked to morphological shifts in the pharyngeal jaw apparatus. For instance, in the Heroine cichlids of Central America, the ability to crush hard-shelled mollusks is a convergent phenotype with multiple evolutionary origins. These durophagous species often have very similar pharyngeal jaw morphologies associated with the pharyngeal jaw apparatus and some of these similarities could be due to phenotypically plastic responses to mechanical stress. I examined the durophagous cichlid Vieja maculicauda for differences in pharyngeal osteology, dentition, and soft tissues when exposed to different diet regimes. Here I discuss the effect on the morphology and …

Systematics And Biogeography Of The Cortinarius Violaceus Group And Sequestrate Evolution In Cortinarius (Agaricales), Emma Harrower

Doctoral Dissertations

Phylogenetics is a powerful tool used for illuminating the diversity of life on Earth, their evolution and their ecology. I created a multi-gene phylogenetic tree of Cortinarius section Cortinarius and uncovered five previously overlooked species, increasing the number of species in the section from seven to twelve. All members of the clade possess both cheilocystidia and pleurocystidia and possess a pigment known as (R)-39,49-dihydroxybphenylalanine. Ancestral state reconstruction estimated that the ancestral host was most likely an angiosperm, switching hosts when encountering novel host species in new lands, and only C. violaceus associating with the Pinaceae in North America. Biogeographic analysis …

Stable Isotopes, Phylogenetics, And Experimental Data Indicate A Unique Nutritional Mode For Rickenella Fibula, A Bryophyte-Associate In The Hymenochaetales, Hailee Brynn Korotkin

Masters Theses

Fungal-bryophyte interactions have been documented in all lineages of bryophytes, however, many of these relationships are poorly understood. The fungus Rickenella fibula is a known associate of various mosses, but results from previous studies have not yielded conclusive evidence of its relationship to mosses or its trophic mode. The Rickenella clade exhibits a wide variety of nutritional modes, including other bryophyte-associated fungi. Here, I combine a broad range of methods, using phylogenetics, stable isotope analyses, PCR assays, in vitro experiments, and genomics to determine the nutritional mode of R. fibula. First, phylogenetic analysis of a supermatrix of 28S rRNA, …

Systematics, Diversification, And Functional Diversity Of Russulaceae (Russulales), Brian Patrick Looney

Doctoral Dissertations

The family Russulaceae is an iconic family of mushroom-forming Basidiomycetes both because of their importance as edible mushrooms in many parts of the world and their species richness in both temperate and tropical forested biomes. While much mycological research has been focused on this group, recent systematic and ecological research has failed to develop a comprehensive or cohesive organization by which to understand the evolutionary relationships, patterns of diversification, or functional importance of the group. Recently, interest in ectomycorrhizal fungi (EmF), of which Russulaceae is a key lineage, has greatly increased due to the recognition of the importance of EmF …

Ecological And Evolutionary Dynamics Of Plant-Soil Feedbacks: Influences On Evolution And Range Dynamics, Michael E. Van Nuland

Doctoral Dissertations

Plants interact with, modify, and are affected by their soil environments. Though plant-soil interactions are well known to be important and active regulators of ecosystem function and community structure, much less is known about how these interactions affect plant evolution. The primary goal of my dissertation was to examine plant-soil interactions under a range of ecological and evolutionary contexts to better understand patterns of biodiversity, ecosystem function, and whole system responses to environmental change. Taking such an eco-evolutionary perspective allows for a holistic understanding of the causes and consequences of complex abiotic and biotic interactions that link ecosystem ecology and …

Molecular Phylogenetic Studies Of The Genera Of Tribe Polygonateae (Asparagaceae: Nolinoideae): Disporopsis, Heteropolygonatum, And Polygonatum., Aaron Jennings Floden

Doctoral Dissertations

The Polygonateae (Asparagaceae) are a subtribe of the Nolinoideae that is redefined here to include three genera which are investigated here: Disporopsis; Heteropolygonatum, and Polygonatum. This group of genera, characterized by their axillary-flowered habit, are closely related but differ greatly in their morphology, cytology, and diversity. A molecular phylogeny is presented to show their relationships to one another and to closely related outgroups based on data from whole chloroplast genomes with low taxonomic sampling. The results show that the genera of the Polygonateae are each monophyletic, and also show that a fourth genus, Maianthemum, that was …

Trait Evolution In Spiders: Perspectives On The Evolution Of Behavioral Syndromes And Web Structures, Jennifer Marie Bosco

Doctoral Dissertations

Organisms have evolved complex behavioral, morphological and physiological traits in response to various selection pressures. These phenotypes are usually composed of many traits that may or may not be genetically or phenotypically correlated. Correlations of both types can lead to evolutionary trade-offs, which may be broken over long evolutionary time periods through such mechanisms as the decoupling of genetic linkages and the development of phenotypic plasticity. Behavioral traits associated with temperament provide an excellent system in which to evaluate underlying mechanisms of the establishment and decoupling of genetic linkages. Other traits, such as the type of web that a spider …

Using Phylogenetic Comparative Methods To Understand Diversification And Geographic Range Evolution, Kathryn Aurora Massana

Doctoral Dissertations

Two key processes that have been modeled in a phylogenetic comparative framework are diversification and historical biogeography. Many questions arise on what process have shaped the abundance (or lack) of species we see today and what influences their survival and interconnectedness with other species. Many methods have been developed to answer these questions. Over the past several decades there has been a rise in parametric modeling and development of more adequate frameworks to answer biological questions of interest. However, many models still lack the incorporation of ecological, mainly biotic factors, which influence the evolution and ecology of species, while accounting …

Tetrameric Photosystem I: From Initial Discovery And Characterization In Chroococcidiopsis Sp. Ts-821 To Exploration Of Its Distribution And Understanding Of Its Significance In Cyanobacteria, Meng Li

Doctoral Dissertations

Photosystem I (PSI) forms trimeric complexes in most characterized cyanobacteria. We had reported the tetrameric form of PSI in the unicellular cyanobacterium, Chroococcidiopsis sp. TS-821 (TS-821). Using Cryo-EM, a 3D model of the PSI tetramer structure at 11.5 [Angstrom] resolution was obtained and a 2D map within the membrane plane of at 6.1 [Angstrom]. In contrast to the three-fold symmetry in trimeric PSI crystal structure from T. elongatus, two different inter-monomer interactions involving PsaLs are found in the PSI tetramer. Phylogenetic analysis based on PsaL protein sequences shows that TS-821 is closely related to heterocyst-forming cyanobacteria. Additionally, this tetrameric …

Investigating Genetic Differences Between Strains Of Janthinobacterium Lividum On Salamanders And In Their Environment, Rhiannon E. Black

Chancellor’s Honors Program Projects

No abstract provided.

Systematics, Diversity And Evolution Of The Suborder Tricholomatineae (Agaricales), Marisol Sanchez Garcia

Doctoral Dissertations

The suborder Tricholomatineae is one of the several major groups of Agaricales, the largest order of mushroom-forming fungi. This suborder contains three families: Tricholomataceae, Entolomataceae and Lyophyllaceae, as well as many genera of incertae sedis. Members of the Tricholomatineae exhibit variation in nutritional mode, including mycoparasites, saprotrophs, termite-associates, bryophyte parasites, and ectomycorrhizal (ECM) symbionts, which makes the clade ideal for studying trophic evolution in fungi from a phylogenetic perspective.

This dissertation combines taxonomy and evolutionary analyses to contribute to the knowledge of fungal diversity and mycorrhizal evolution. First, I present a systematic revision of the family Tricholomataceae within a …

Computational Identification Of Terpene Synthase Genes And Their Evolutionary Analysis, Qidong Jia

Doctoral Dissertations

Terpenoids, the largest and most structurally and functionally diverse class of natural compounds on earth, are mostly synthesized by plants to be involved in various plant environment interactions. Some terpenoids are classified as primary metabolites essential for plant growth and development. Terpene synthases (TPSs), the key enzymes for terpenoid biosynthesis, are the major determinant of the tremendous diversity of terpenoid carbon skeletons. The TPS genes represent a mid-size family of about 30-100 functional genes in almost all major sequenced plant genomes. TPSs are also found in fungi and bacteria, but microbial TPS genes share low levels of sequence similarity and …

Biochemistry And Evolution Of The Phytohormone-Methylating Sabath Methyltransferase In Plants, Minta Chaiprasongsuk

Doctoral Dissertations

Known members of Phytohormone-methylating compounds are plant synthesis compounds that serve as attractants of other living organisms beneficial to the plants or as defense against other biotic as well as abiotic agents. To increase their fitness and survival in a stressful environment plants produce distinct sets of phytohormone-methylating compounds. Plant genomes can encode the necessary enzymes to acquire the ability to make new specialized compounds during evolution. This dissertation aims to investigate the biochemical and biological functions and evolution of SABATH genes in different lineages of plants. Black cottonwood, Brachypodium and Norway spruce genome were used as the model for …

Using Phylogenetics To Understand The Evolutionary Relationships Of Hibiscus Section Furcaria, Whitaker Matthew Hoskins

Masters Theses

Neopolyploids constitute at least 35% of known species of angiosperms, and because polyploidization is a pertinent process in plant diversification and domestication, it is a thriving field of study. Hibiscus section Furcaria includes several groups of polyploids in addition to ten known diploid species. In previous studies genome groups for Hibiscus section Furcaria were determined through artificial hybridization experiments and patterns of biogeography were elucidated based on the distribution of diploids and polyploids. For instance, the Australian hexaploids contain 3 genomes (designated G, J, and V) and are thought to have developed from a polyploidization event between an African diploid …

Systematics And Diversification Patterns Of Morphologically And Ecologically Diverse Lineages Of Agaricomycetes: Clavariaceae And Cantharellales, Joshua Mark Birkebak

Doctoral Dissertations

The recent advent of molecular tools and methods to understand the diversity of living organisms allows for exploration of former untestable theories concerning the diversity of fungi. Here we assess the morphologically based classification of the family Clavariaceae in light of molecular phylogenetic reconstruction and propose a revised classification base on natural assemblages. We used stable isotope ratios to uncover a biotrophic nutritional mode for much of the family, which had not been well understood historically. We also investigate several enigmatic lineages of agaricoid or cantharelloid fruiting body producing fungi within a clade of otherwise clavarioid fruiting bodies. We provide …

A New Adaptive Landscape: Urbanization As A Strong Evolutionary Force, Lauren Christie Breza

Masters Theses

Urbanization is rapidly increasing as human population growth steadily grows, but there is little consensus of the ecological consequence of this population shift and almost no information of the evolutionary consequences for local biodiversity. Nearly two-thirds of the world’s population will live in city centers by 2050 with profound impacts on landscapes that can act as important agents of selection. This study aims to identify 1) the net effect of urbanization on species richness, 2) how phylogenetic diversity varies between urban and rural sites, and 3) the strength of urbanization as a selection pressure. First, a meta-analysis was conducted in …

Evolution And Phylogeny Of The Parasitoid Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke

Doctoral Dissertations

The first molecular phylogenetic analysis of the agriculturally important parasitoid subfamily Phasiinae (Diptera: Tachinidae) is presented, estimated from 128 worldwide taxa (80 genera) and approximately 7.6 kilobases of nuclear data. Special emphasis is placed on taxa with controversial taxonomic placement. The resultant phylogenetic tree is used to reconstruct ancestral character states, trace the evolution of significant adaptive traits within the Tachinidae, and test hypotheses about the classification of Phasiinae. Subfamily placements of the taxa Eutherini, Epigrimyiini, Litophasia, Strongygastrini, and Parerigonini are confidently resolved, the former three within Dexiinae and the latter two within Phasiinae. Due to sparse molecular evidence, …

Mechanisms For Social Influence, Jeremy David Auerbach

Masters Theses

Throughout the thesis, I study mathematical models that can help explain the dependency of social phenomena in animals and humans on individual traits. The first chapter investigates consensus building in human groups through communication of individual preferences for a course of action. Individuals share and modify these preferences through speaker listener interactions. Personality traits, reputations, and social networks structures effect these modifications and eventually the group will reach a consensus. If there is variation in personality traits, the time to reach consensus is delayed. Reputation models are introduced and explored, finding that those who can best estimate the average initial …

Forest Or Phylogeny?: Untangling Phylogenetic Signal From Selection Pressure Using Barronopsis Texans, Alexandra I. Chatman

Chancellor’s Honors Program Projects

No abstract provided.

Plasticity In A Changing World: Phenotypic Variability In Boechera Stricta Across Space And Time, Caroline Daws

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

While some plants are mobile and able to physically distribute to more suitable environments, other plants have limited dispersal ability and must find alternate ways to adjust to changing conditions in situ through adaptation or plasticity. Predicted changes in abiotic pressures, including drought stress and warmer temperatures, may influence the phenotypic expression of traits in plant populations through these mechanisms. In this study, we used a reciprocal transplant approach to investigate the temporal and spatial patterns of plasticity in a native perennial mustard, Boechera stricta, in the Rocky Mountains. Specifically, we explore how a temporal gradient that reflects drought stress …

To Play Or Not To Play? That’S A Resource Abundance Question, Jeremy David Auerbach, Andrew R. Kanarek, Gordon M. Burghardt

Faculty Publications and Other Works -- Ecology and Evolutionary Biology

Although play occurs in a wide variety of animals, models of the origins of play behavior are lacking. We propose a novel computational model exploring the evolution of non-social frivolous play. Asexually reproducing semelparous animals can either rest or forage. Foraging occurs when an organism is below an energy threshold. Success is determined by the combination of skill and availability of resources, which declines over time but replenishes for each generation. Play was introduced as a mutant strategy: a frivolous activity that uses energy and increases the probability of dying over resting with no direct fitness benefit. Simulations show that …

Linking Dna Polymorphisms And Populations' Evolutionary History, Ivan Juric

Doctoral Dissertations

This dissertation seeks to provide an understanding of how different evolutionary forces can affect the DNA polymorphism patterns. I use a combination of individual-based simulations and analytical to examine polymorphism patterns during divergence with gene flow, hybridization and territory expansion. In the first chapter, I show how during divergence with gene flow the appearance and maintenance of “Genomic Islands of Divergence” can be explained using standard population genetics terminology, thus removing some of the confusion recently introduced in that literature. In the second chapter I derive the expressions for the distribution of coalescent times and pairwise differences in a hybridization …