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Reproductive Effort And Lipid Dynamics Of The Emerald Shiner (Notropis Atherinoides) In The Upper Niagara River, New York, Christopher A. Osborne 2018 State University of New York College at Buffalo - Buffalo State College

Reproductive Effort And Lipid Dynamics Of The Emerald Shiner (Notropis Atherinoides) In The Upper Niagara River, New York, Christopher A. Osborne

Biology Theses

Life history theory predicts that reproductive characteristics of organisms will be shaped by biotic and abiotic factors to maximize their overall fitness. In this study, I investigated how growth, reproductive effort, and lipid dynamics vary ontogenetically and seasonally for emerald shiners (Notropis atherinoides) in the upper Niagara River. Growth rates were highest in age 2 shiners and lower in age 1 and age 3 individuals. Evidence of reproduction was found beginning at age 1, and reproductive investment as measured by ovarian lipid content was lowest in age 1 and age 2 individuals and greatest in age 3 fish. …


Evolutionary Conservation Of Midline Repulsion By Robo Family Receptors In Flies And Mice, Allison Loy 2018 University of Arkansas, Fayetteville

Evolutionary Conservation Of Midline Repulsion By Robo Family Receptors In Flies And Mice, Allison Loy

Biological Sciences Undergraduate Honors Theses

As the nervous system develops in animal embryos, neuronal axons are guided to their synaptic targets by extra cellular cues that signal through axon guidance receptors expressed on the surface of the axon. In animals with bilateral symmetry, one of the important decisions made by nearly every axon in the embryonic nervous system is whether to stay on its own side of the body, or to cross the midline and connect to cells on the opposite side. The Roundabout (Robo) family is an evolutionarily conserved group of axon guidance receptors that regulate midline crossing in a wide range of animal …


Phylogeny And Evolutionary Genomics Of Non-Photosynthetic Diatoms, Anastasiia Onyshchenko 2018 University of Arkansas, Fayetteville

Phylogeny And Evolutionary Genomics Of Non-Photosynthetic Diatoms, Anastasiia Onyshchenko

Graduate Theses and Dissertations

Diatoms are prolific photosynthesizers responsible for some 20% of global primary production. In real terms, the oxygen in one of every five breaths traces back to photosynthesis by marine diatoms. Among the tens of thousands of diatom species, a small handful of colorless diatom species in the genus Nitzschia have lost photosynthesis altogether and rely exclusively on extracellular organic carbon for growth. I used DNA sequence data to reconstruct the phylogeny of this group, and found that nonphotosynthetic diatoms are monophyletic, indicating that photosynthesis was lost just one time over the course of some 200 million years of diatom evolution. …


Using Molecular Markers To Trace The Population History Of Volant Organisms At Differing Temporal Scales, Noah A. Burg 2018 CUNY Graduate Center

Using Molecular Markers To Trace The Population History Of Volant Organisms At Differing Temporal Scales, Noah A. Burg

Dissertations, Theses, and Capstone Projects

Using molecular markers to test phylogenetic and phylogeographic hypotheses is critical for tracking the population origin of invasive, introduced species (Chapter 2, Chapter 4) and to identify the systematic relationships of disparate lineages at both shallow and deep evolutionary time scales (Chapters 3, Chapter 4). In this thesis, Sanger Sequencing was used to generate datasets based on fresh and preserved tissue from specimens collected in the field, as well as museum tissue vouchers granted from various institutions in the US and Europe. In combining these source materials, data were generated for three focal studies: 1) In the first research section …


Niche Shifts, Species Distributions, And Genetic Diversity In Gymnophthalminae Lizards, With A Focus On Microclimates And Thermophysiology, Maria Strangas 2018 CUNY Graduate Center

Niche Shifts, Species Distributions, And Genetic Diversity In Gymnophthalminae Lizards, With A Focus On Microclimates And Thermophysiology, Maria Strangas

Dissertations, Theses, and Capstone Projects

The environmental niche is a central organizing concept in the study of ecology and evolution, as the environmental conditions in which species can persist (their fundamental niches) and the conditions in which they occur (their realized niches) can shape spatial and temporal patterns of biodiversity at multiple scales. How organisms at different levels of biological organization are affected by environmental heterogeneity has consequences for the distribution of genetic and phenotypic diversity, yet the mechanisms through which this occurs are poorly studied. In this dissertation, I present three research chapters that explore how species’ traits and their microclimatic environments shape biodiversity …


A Contribution Toward A Global Monograph Of Gyroporus: Taxonomy, Phylogeny, Biogeography, Naveed Davoodian 2018 CUNY Graduate Center

A Contribution Toward A Global Monograph Of Gyroporus: Taxonomy, Phylogeny, Biogeography, Naveed Davoodian

Dissertations, Theses, and Capstone Projects

Gyroporus (Sclerodermatineae, Boletales, Agaricomycetes, Basidiomycota, Fungi) is a genus of ectomycorrhizal mushroom-forming fungi distributed throughout the world in suitable habitats. Previous attempts to untangle the diversity of this genus proved difficult due to the presence of semi-cryptic species and equivocal results from phylogenetic analysis of ribosomal RNA markers. To overcome these obstacles, a combined taxonomic and phylogenetic (emphasizing protein-coding genes) approach is used here to delimit species and elucidate geographic and evolutionary patterns of Gyroporus. Careful study of relevant literature and herbarium specimens was augmented by field work in North America, Australia, and East Asia for observation and collection …


Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xvi. Compsobuthus Maidensis Sp. N. (Buthidae) From Somaliland, František Kovařík 2018 Marshall University

Scorpions Of The Horn Of Africa (Arachnida, Scorpiones). Part Xvi. Compsobuthus Maidensis Sp. N. (Buthidae) From Somaliland, František Kovařík

Euscorpius

Compsobuthus maidensis sp. n. from Somaliland is described and fully complemented with color photos of specimens, as well as its habitat. Data on the occurrence of the genus Compsobuthus Vachon, 1949 in the Horn of Africa is summarized.


Energetic Tradeoffs Control The Size Distribution Of Aquatic Mammals, William Gearty, Craig R. McClain, Jonathan Payne 2018 University of Nebraska - Lincoln

Energetic Tradeoffs Control The Size Distribution Of Aquatic Mammals, William Gearty, Craig R. Mcclain, Jonathan Payne

School of Biological Sciences: Faculty Publications

Four extant lineages of mammals have invaded and diversified in the water: Sirenia, Cetacea, Pinnipedia, and Lutrinae. Most of these aquatic clades are larger bodied, on average, than their closest land-dwelling relatives, but the extent to which potential ecological, biomechanical, and physiological controls contributed to this pattern remains untested quantitatively. Here, we use previously published data on the body masses of 3,859 living and 2,999 fossil mammal species to examine the evolutionary trajectories of body size in aquatic mammals through both comparative phylogenetic analysis and examination of the fossil record. Both methods indicate that the evolution of an aquatic lifestyle …


The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams 2018 University of South Florida

The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams

USF Tampa Graduate Theses and Dissertations

The frequency with which individuals do not develop their third molars, or wisdom teeth, is increasing worldwide. This current topic of human evolution is relevant to the research of anthropologists, geneticists, dentists, and other researchers involved in the study of human dentition. Many explanations have been offered to account for the prevalence of molar agenesis including, evolutionary, environmental, and genetic theories. The purpose of this research project is to determine the frequency of third molar agenesis and investigate the relationship between third molar agenesis and maxillomandibular jaw dimensions in a sample of orthodontic patients. This research tests the hypotheses that: …


Another Scientific Revolution: Now Yielding A 'Cosmic Biology' Consistent With Natural Theology, Theodore Walker 2018 Southern Methodist University

Another Scientific Revolution: Now Yielding A 'Cosmic Biology' Consistent With Natural Theology, Theodore Walker

Perkins Faculty Research and Special Events

Beyond the Copernican revolution, another scientific revolution is now in process. Inspired by Sir Fred Hoyle and others, this contemporary extension of the Copernican revolution is replacing biology conceived as exclusively Earth science with biology conceived as including study of stellar evolution and cosmic evolution. Furthermore, astrobiology, panspermia, and cosmic biology (Hoyle and Wickramasinghe) are advancing in ways consistent with natural theology, especially with panentheism. Some of this was anticipated and advocated by Alfred North Whitehead, Charles Hartshorne, and other philosophers of nature.


Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xv. Review Of The Genus Gint Kovařík Et Al., 2013, With Description Of Three New Species From Somaliland (Scorpiones, Buthidae), František Kovařík, Graeme Lowe, Pavel Just, Ahmed Ibrahim Awale, Hassan Sh Abdirahman Elmi, František Šťáhlavský 2018 Charles University

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xv. Review Of The Genus Gint Kovařík Et Al., 2013, With Description Of Three New Species From Somaliland (Scorpiones, Buthidae), František Kovařík, Graeme Lowe, Pavel Just, Ahmed Ibrahim Awale, Hassan Sh Abdirahman Elmi, František Šťáhlavský

Euscorpius

We describe herein three new species of Buthidae: Gint amoudensis sp. n., G. gubanensis sp. n., and G. maidensis sp. n. from Somaliland. Additional information is provided on the taxonomy and distribution of other species of the genus Gint, fully complemented with color photos of live and preserved specimens, as well as of their habitat. The hemispermatophores of most Gint species are illustrated and described for the first time. In addition to the analyses of external morphology and hemispermatophores, we also describe the karyotype of four Gint species. The number of chromosomes is different for every one …


Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer 2018 CUNY Graduate Center

Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer

Publications and Research

The evolutionary emergence of humans’ remarkably economical walking gait remains a focus of research and debate, but experi- mentally validated approaches linking locomotor capability to postcranial anatomy are limited. In this study, we integrated 3D morphometrics of hominoid pelvic shape with experimental mea- surements of hip kinematics and kinetics during walking and climbing, hamstring activity, and passive range of hip extension in humans, apes, and other primates to assess arboreal–terrestrial trade-offs in ischium morphology among living taxa. We show that hamstring-powered hip extension during habitual walking and climbing in living apes and humans is strongly predicted, and likely constrained, by …


The Mechanism Of Biotremor Production In The Veiled Chameleon (Chamaeleo Calyptratus), Samuel Tegge 2018 Western Kentucky University

The Mechanism Of Biotremor Production In The Veiled Chameleon (Chamaeleo Calyptratus), Samuel Tegge

Masters Theses & Specialist Projects

Vibratory communication has evolved in numerous animal groups, including insects, spiders, fishes, mammals, and was recently discovered in veiled chameleons (Chamaeleo calyptratus). I examined the mechanism by which C. calyptratus produce these biotremors. Muscle activity data were gathered during simulated anti-predator responses via electromyography (EMG) with simultaneous recordings of biotremor production using an accelerometer. I correlated EMG data with the accelerometer data to implicate the muscles responsible for the production of the biotremors. Mixed-effect linear regression models described the mechanism, and a model selection framework determined which model fit the data best. I then used an analysis of variance to …


The Evolutionary History Of Nebraska Deer Mice: Local Adaptation In The Face Of Strong Gene Flow, Susanne P Pfeifer, Stefan Laurent, Vitor C. Sousa, Catherine R. Linnen, Matthieu Foll, Laurent Excoffier, Hopi E. Hoekstra, Jeffrey D. Jensen 2018 Ecole Polytechnique Fédérale de Lausanne, Switzerland

The Evolutionary History Of Nebraska Deer Mice: Local Adaptation In The Face Of Strong Gene Flow, Susanne P Pfeifer, Stefan Laurent, Vitor C. Sousa, Catherine R. Linnen, Matthieu Foll, Laurent Excoffier, Hopi E. Hoekstra, Jeffrey D. Jensen

Biology Faculty Publications

The interplay of gene flow, genetic drift, and local selective pressure is a dynamic process that has been well studied from a theoretical perspective over the last century. Wright and Haldane laid the foundation for expectations under an island-continent model, demonstrating that an island-specific beneficial allele may be maintained locally if the selection coefficient is larger than the rate of migration of the ancestral allele from the continent. Subsequent extensions of this model have provided considerably more insight. Yet, connecting theoretical results with empirical data has proven challenging, owing to a lack of information on the relationship between genotype, phenotype, …


Selection Perception: Views On The Theory Of Evolution Among Residents Of Moshi, Tanzania, Robin Waterman 2018 SIT Study Abroad

Selection Perception: Views On The Theory Of Evolution Among Residents Of Moshi, Tanzania, Robin Waterman

Independent Study Project (ISP) Collection

The theory of evolution is a major tenet of biological science and has many practical applications, particularly in agriculture, medicine, and conservation. Nevertheless, there is significant opposition to the theory and its incorporation into school curricula, largely on religious grounds. This disconnect between public opinion and scientific opinion has been studied at length in the US and to some extent in other industrialized nations, but little is known about the issue in other communities around the world. This paper will use the town of Moshi, Tanzania as a case study in community views and knowledge about the theory of evolution. …


Molecular Phylogenetics Of Floridian Boletes, Arian Farid 2018 University of South Florida

Molecular Phylogenetics Of Floridian Boletes, Arian Farid

USF Tampa Graduate Theses and Dissertations

The boletes are macrofungi which have undergone extensive taxonomic revisions since the advent of molecular tools. To further our understanding of the boletes in peninsular Florida, we sequenced two common Floridian boletes, and analyzed them with molecular phylogenetic tools. Boletus rubricitrinus, a common Florida bolete often found in lawns under Quercus, and likely has a distribution that extends to Texas. Based on ITS and LSU sequences and morphological studies, this species belongs in the genus Pulchroboletus. As the holotype is in poor condition, an epitype is established here. A thorough description of macroscopic and microscopic features is also provided for …


Evolution Of Alu Elements In The Saimiri And Papio Lineages Of Primates, Jasmine Nicole Brown Baker 2018 Louisiana State University and Agricultural and Mechanical College

Evolution Of Alu Elements In The Saimiri And Papio Lineages Of Primates, Jasmine Nicole Brown Baker

LSU Doctoral Dissertations

Alu elements are approximately 300 base pair (bp) primate specific non- autonomous retrotransposons. Alu elements, a short interspersed element (SINE), account for high copy numbers in all primate genomes. Numerous Alu element subfamilies have undergone varying degrees of activity and amplification within primates. Identification of these subfamilies has proved to be very informative in elucidating phylogenies and as phylogenomic markers. Squirrel monkeys, genus Saimiri, are one of the most well-known neotropical primates and the second most commonly used laboratory monkey. Squirrel monkey species diverged approximately 1.5 million years ago and are native to South America. Despite being well-known, there …


Grooming Behaviors Of, Lauren N. Williams 2018 University of South Florida

Grooming Behaviors Of, Lauren N. Williams

USF Tampa Graduate Theses and Dissertations

The giant freshwater shrimp, Macrobrachium rosenbergii is a large species of prawn grown extensively in aquaculture settings. A social hierarchy exists within the males of this species, representing three distinct male morphotypes. These male morphotypes differ in their behavior, physiology, and morphology and include the largest blue-clawed males (BC males), moderately- sized orange-clawed males (OC males), and the undifferentiated small-clawed males (SM males). All individuals of this species perform grooming behaviors to rid themselves of body fouling which can impede important functions such as movement, respiration, chemoreception, and reproduction. Grooming behaviors in crustaceans often utilize specialized structures called setae, which …


Genetic Differentiation Between Two Species Of Buckwheat (Eriogonum), Paul G. Wolf, Jenessa B. Lemon 2018 Utah State University

Genetic Differentiation Between Two Species Of Buckwheat (Eriogonum), Paul G. Wolf, Jenessa B. Lemon

Browse all Datasets

Discovering the extent of genetic differentiation between closely related taxa facilitates decisions regarding species protection under the Endangered Species Act. Here, we analyze genotype data to explore the relatedness of two buckwheat species: Eriogonum soredium Reveal- a narrow endemic under consideration for protection, and a widespread close relative, Eriogonum shockleyi S. Watson. Eriogonum soredium grows only on Ordovician limestone outcroppings in west central Utah, whereas the range of E. shockleyi is broad, spanning the western United States from Colorado to California, and Idaho to Arizona. Eriogonum shockleyi is suspected of hybridizing with other buckwheats throughout this range. We detected higher …


Charles Darwin, Will You Be My Valentine?, Meredith Bennett 2018 Duquesne University

Charles Darwin, Will You Be My Valentine?, Meredith Bennett

D.U.Quark

No abstract provided.


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