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Zebrafish (Danio Rerio) Hoxb6: An Exploration Into The Divergence Of Genomic Dna Sequence And Gene Expression Across Teleost Fishes Post-Genome Duplication, Amber Lynn Rittgers, Pierre Le Pabic, Adam Davis 2021 University of Georgia

Zebrafish (Danio Rerio) Hoxb6: An Exploration Into The Divergence Of Genomic Dna Sequence And Gene Expression Across Teleost Fishes Post-Genome Duplication, Amber Lynn Rittgers, Pierre Le Pabic, Adam Davis

Georgia Journal of Science

Hoxb6 is an evolutionarily conserved developmental regulatory gene that functions, in part, to pattern several organs and organ systems within the embryonic trunk during vertebrate embryogenesis. The cis-regulatory circuitry mediating trunk expression in mouse (Mus musculus) may be conserved across gnathostome vertebrates, as several other species show similar trunk expression patterns, including chicken (Gallus gallus), dogfish shark (Scyliorhinus canicula), and several teleost fishes. A whole genome duplication event that occurred in the lineage leading to teleost fishes has generated at least two Hoxb6 genes, hoxb6a and b6b. Two teleost fishes of the …


The Phoenix, Fernanda Perez-Alvarez 2021 College of the Holy Cross

The Phoenix, Fernanda Perez-Alvarez

Montserrat Annual Writing Prize

This article uses a mythical creature, the phoenix, to examine and illustrate the biological principles for generation of an adult body plan from a single cell. Using the study of developmental biology, it explores the cellular and molecular biology that underpins the massive complexity of creating an adult body plan. It also explores the similarities and differences between different embryos, and how nature and evolution have shaped the biology of those embryos to create different body plans.


Alfred Russel Wallace Notes 17: More On The South Asian Connection, Charles H. Smith 2021 Western Kentucky University

Alfred Russel Wallace Notes 17: More On The South Asian Connection, Charles H. Smith

Faculty/Staff Personal Papers

During his school years the arts and cultural historian and metaphysician Ananda Coomaraswamy (1877-1947) was clearly influenced by Alfred Russel Wallace, and is known later to have corresponded with, and supplied information to, him. Up to now the connections involved had been obscure, but a new investigation suggests that Wallace had previously interacted with Ananda’s mother and/or father.


Molecular And Morphological Consequences Of Post-Glacial Contact Among Lineages Of Northern Short-Tailed Shrews (Blarina Brevicauda) In Eastern North America, Ellen Michels 2021 Northern Michigan University

Molecular And Morphological Consequences Of Post-Glacial Contact Among Lineages Of Northern Short-Tailed Shrews (Blarina Brevicauda) In Eastern North America, Ellen Michels

All NMU Master's Theses

During the Pleistocene, advancing glacial ice fragmented populations of species, which restricted populations from expanding, ultimately inhibiting gene flow. As glaciers receded, expansion out of unglaciated-isolated areas was possible. In addition to glacial barriers, landscape features such as rivers and mountain ranges served as barriers to dispersal of populations during the Pleistocene, influencing the phylogeography of multiple species. Though divergence between multiple lineages is a common feature of North American mammal diversity, circumstances that affected the post-glacial expansion of structured diversity within regions are less well-documented. Northern short-tailed shrews (Blarina brevicauda) are restricted to eastern North America, yet …


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

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 …


Alfred Russel Wallace Notes 16: The Flexible Wallace, Charles H. Smith 2021 Western Kentucky University

Alfred Russel Wallace Notes 16: The Flexible Wallace, Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (1823−1913), though a naturalist of considerable renown, has sometimes been accused of inflexibility and inconsistency in his thinking. Many of his critics, however, ignore his basic approach to knowledge accumulation, which was explicitly incremental, based on a perceived need for constant reconsideration. Here, I: (1) identify five groups of Wallace critics who seem to be operating with prior agendas, and (2) provide lists of subjects on which he either changed his mind, or remained constant, according to individual situation.


Micro- And Macroevolution Of Drab Plumage Color In Birds, Rafael Marcondes 2021 Louisiana State University

Micro- And Macroevolution Of Drab Plumage Color In Birds, Rafael Marcondes

LSU Doctoral Dissertations

I address the evolution of drab bird colors at micro- and macroevolutionary scales. I use as a study system the Furnariida, a clade of >600 Neotropical passerine species that, despite tremendous ecological and morphological diversity, are colored almost exclusively in shades of brown and grey produced by melanin pigments.

In chapters two and three, I took a macroevolutionary approach and showed that (1) plumage colors in the Furnariida evolve at similar rates in a monochromatic clade, males of a dichromatic clade, and females of a dichromatic clade; (2) ventral plumage color evolves faster than dorsal; (3) bird species that occupy …


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

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 2021 Swarthmore College

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 …


Habitat Characteristics Of Two Scorpion Species, Liocheles Australasiae (Fabricius, 1775) And Isometrus Maculatus (De Geer, 1778) In Miyako Islands, Japan, Kazusa Kawai 2021 Marshall University

Habitat Characteristics Of Two Scorpion Species, Liocheles Australasiae (Fabricius, 1775) And Isometrus Maculatus (De Geer, 1778) In Miyako Islands, Japan, Kazusa Kawai

Euscorpius

Scorpion surveys were conducted in the five islands: Miyakojima, Ikemajima, Kurimajima, Irabujima, and Shimojishima (Miyako Islands, part of Nansei/Ryukyu Islands of Japan). Eight individuals of Liocheles australasiae (Hormuridae) and 16 individuals of Isometrus maculatus (Buthidae) were observed in a total of 10 points on four islands, except Ikemajima. The localities of both species are recorded in this survey, focusing on altitude, distance from the nearest coast, and sunlight. The lowest temperatures in the habitat are also examined, and the cold tolerance of the species is discussed.


Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxvi. Records Of Hottentotta Polystictus (Pocock, 1896), With Descriptions Of H. Haudensis Sp. N. And H. Nigrimontanus Sp. N. (Buthidae) From Somaliland, František Kovařík, Graeme Lowe 2021 Marshall University

Scorpions Of The Horn Of Africa (Arachnida: Scorpiones). Part Xxvi. Records Of Hottentotta Polystictus (Pocock, 1896), With Descriptions Of H. Haudensis Sp. N. And H. Nigrimontanus Sp. N. (Buthidae) From Somaliland, František Kovařík, Graeme Lowe

Euscorpius

The distribution of Hottentotta polystictus (Pocock, 1896) is summarized according to recently confirmed records. Two new species, Hottentotta haudensis sp. n. and H. nigrimontanus sp. n. from the Somaliland, are described, compared with H. polystictus, and fully illustrated with color photos showing their morphology, habitus and collection areas. H. haudensis sp. n. is the smallest known species of the genus Hottentotta Birula, 1908, while H. nigrimontanus sp. n. is larger than H. polystictus.


Predation Of Ananteris Spp. (Scorpiones: Buthidae) By Ants And A Social Wasp (Hymenoptera: Formicidae, Vespidae) In Panama, Central America, Roberto Miranda, Luis F. de Armas, Roberto A. Cambra 2021 Marshall University

Predation Of Ananteris Spp. (Scorpiones: Buthidae) By Ants And A Social Wasp (Hymenoptera: Formicidae, Vespidae) In Panama, Central America, Roberto Miranda, Luis F. De Armas, Roberto A. Cambra

Euscorpius

Two events of predation on Ananteris spp. were observed in the Parque Nacional Darién, Darién Province, Panama. The first case involved the social wasp Agelaia centralis (Cameron, 1907) (Vespidae); the second one, a ponerine ant Leptogenys cf. cuneata Lattke, 2011 (Formicidae). This is the first time that predation by a social wasp on a scorpion is observed. They also represent the first recorded predators for Panamanian Ananteris species.


Fetilinia Dentator Gen. Et Sp. N. From Pakistan (Scorpiones: Buthidae), Graeme Lowe, František Kovařík 2021 Marshall University

Fetilinia Dentator Gen. Et Sp. N. From Pakistan (Scorpiones: Buthidae), Graeme Lowe, František Kovařík

Euscorpius

We describe from northern Pakistan a new buthid genus Fetilinia gen. n., monotypic with type species F. dentator sp. n., belonging to the Palaearctic ‘Buthus’ group. It bears some similarities to Kraepelinia Vachon, 1974, in having enlarged metasomal dentition, and to Orthochirus Karsch, 1891, and related genera in having a trapezoidal carapace and small abbreviated pedipalps.


Single-Locus Species Delimitation And Ecological Niche Modeling Provide Insights Into The Evolution, Historical Distribution, And Taxonomy Of The Pacific Chorus Frogs, Robert C. Jadin, Sarah A. Orlofske, Tereza Jezkova, Christopher Blair 2021 University of Wisconsin - Eau Claire

Single-Locus Species Delimitation And Ecological Niche Modeling Provide Insights Into The Evolution, Historical Distribution, And Taxonomy Of The Pacific Chorus Frogs, Robert C. Jadin, Sarah A. Orlofske, Tereza Jezkova, Christopher Blair

Publications and Research

The Pacific chorus frogs are a complex of three wide-ranging species (i.e. Hyliola hypochondriaca, Hyliola regilla, Hyliola sierra) whose current taxonomy remains unresolved. We conducted species delimitation analyses of these taxa using fragments of the cytochrome b and 12S–16S mtDNA genes to assess the species diversity. Importantly, we included samples from new locations throughout the range to better understand species distributions and identify potential contact zones among clades. Our analyses revealed three slightly parapatric but distinct species-level clades. Molecular dating revealed that these species began diverging in the Pleistocene c. 1.4 Mya with H. hypochondriaca and …


An Exceptionally Small New Polycotylid Plesiosaur (Reptilia: Sauropterygia) With Raptorial Eyes From The Western Interior Seaway Of North America, Robert O’Brien Clark 2021 Marshall University

An Exceptionally Small New Polycotylid Plesiosaur (Reptilia: Sauropterygia) With Raptorial Eyes From The Western Interior Seaway Of North America, Robert O’Brien Clark

Theses, Dissertations and Capstones

Polycotylidae is a family of plesiosaurian marine reptiles that evolved during the Early Cretaceous and radiated into multiple genera during the Late Cretaceous, achieving a worldwide distribution. Derived polycotylids of the subclade Polycotylinae have a gracile and elongated rostrum, homodont dentition, an extended mandibular symphysis, and foreshortened temporal fenestrae. In this thesis, I describe a small and highly derived new polycotylid taxon based on three specimens from the Campanian of the Western Interior Seaway in North America. A high number of maxillary teeth, fused neural arches, propodials with well-defined facets, and heavily remodeled cortical bone indicate the specimens are adults, …


Dog And Owner Characteristics Predict Training Success, Jeffrey R. Stevens, London M. Wolff, Megan Bosworth, Jill Morstad 2021 University of Nebraska-Lincoln

Dog And Owner Characteristics Predict Training Success, Jeffrey R. Stevens, London M. Wolff, Megan Bosworth, Jill Morstad

Jeffrey Stevens Publications

Teaching owners how to train their dogs is an important part of maintaining the health and safety of dogs and people. Yet we do not know what behavioral characteristics of dogs and their owners are relevant to dog training or if owner cognitive abilities play a role in training success. The aim of this study is to determine which characteristics of both dogs and owners predict success in completing the American Kennel Club Canine Good Citizen training program. Before the first session of a dog training course, owners completed surveys evaluating the behavior and cognition of their dog and themselves. …


Are Capuchin Monkeys (Sapajus Spp.) Sensitive To Lost Opportunities? The Role Of Opportunity Costs In Intertemporal Choice, Elsa Addessi, Valeria Tierno, Valentina Focaroli, Federica Rossi, Serena Gastaldi, Francesca De Petrillo, Fabio Paglieri, Jeffrey R. Stevens 2021 University of Nebraska-Lincoln

Are Capuchin Monkeys (Sapajus Spp.) Sensitive To Lost Opportunities? The Role Of Opportunity Costs In Intertemporal Choice, Elsa Addessi, Valeria Tierno, Valentina Focaroli, Federica Rossi, Serena Gastaldi, Francesca De Petrillo, Fabio Paglieri, Jeffrey R. Stevens

Jeffrey Stevens Publications

Principles of economics predict that the costs associated with obtaining rewards can influence choice. When individuals face choices between a smaller, immediate option and a larger, later option, they often experience opportunity costs associated with waiting for delayed rewards because they must forego the opportunity to make other choices. We evaluated how reducing opportunity costs affects delay tolerance in capuchin monkeys. After choosing the larger option, in the High cost condition, subjects had to wait for the delay to expire, whereas in the Low cost different and Low cost same conditions, they could perform a new choice during the delay. …


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 2021 Central Washington University

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 …


A Multispecies Perspective Into Dietary Genetic Adaptations And Ancient Migration In The Peruvian Andes, Kelsey Jorgensen 2021 Wayne State University

A Multispecies Perspective Into Dietary Genetic Adaptations And Ancient Migration In The Peruvian Andes, Kelsey Jorgensen

Wayne State University Dissertations

Successful adaptation to the high-elevation Andes would have required both cultural and biological adaptations by early human populations. These past adaptations continue to shape the evolutionary outcomes of both humans and non-human species today. A multispecies perspective was used to examine how humans and non-human creatures, specifically insects, were shaped by past human adaptations. This dissertation asked two primary questions: 1) Given the importance and evolutionary history of potato consumption in the Peruvian Andes, is a genetic adaptation to better digest potato starch detectable in present-day Peruvians? and 2) Using the Andean Potato Weevil (APW) phylogeny as a proxy, what …


Comparative Conservation Genomics Of A Suite Of Imperiled Freshwater Mussels, Scott C. Meyer 2021 Georgia Southern University

Comparative Conservation Genomics Of A Suite Of Imperiled Freshwater Mussels, Scott C. Meyer

College of Graduate Studies: Theses & Dissertations

Maintenance of genetic diversity is a critical component to the management and recovery of imperiled species. By ensuring that a species’ genetic diversity is maintained, issues like inbreeding depression and loss of local adaptation can be prevented. However, the genetic diversity of many species are not well-characterized, and the factors that influence a species’ genetic diversity are often not well understood. In the case of imperiled unionid freshwater mussels, it is important to conduct conservation genetic assessments to aid in their management and preserve genetic diversity. This is the first study to conduct a comparative conservation genomic assessment for eight …


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