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Phylogenetics And Mating System Evolution In The Southern South American Valeriana (Valerianaceae), Lauren A. Gonzalez 2014 University of New Orleans

Phylogenetics And Mating System Evolution In The Southern South American Valeriana (Valerianaceae), Lauren A. Gonzalez

LSU New Orleans Theses and Dissertations

Species of Valerianaceae in South America represent one of the best examples of rapid diversification on a continental scale. The phylogeny of Valerianaceae has received a lot of attention within the last 10 years, but relationships among the South American species are fairly unresolved. Results from previous studies have not been well resolved with traditional genetic markers, most likely due to its recent and rapid radiation. Species in this clade exhibit a variety mating systems and inflorescence types. For the first part of this research I used several traditional plastid markers, and 3 new low copy nuclear markers to better …


Comparative Population Assessments Of Nautilus Sp. In The Philippines, Australia, Fiji, And American Samoa Using Baited Remote Underwater Video Systems, Gregory Jeff Barord, Frederick Dooley, Andrew Dunstan, Anthony Ilano, Karen N. Keister, Heike Neumeister, Thomas Preuss, Shane Schoepfer, Peter D. Ward 2014 CUNY Brooklyn College

Comparative Population Assessments Of Nautilus Sp. In The Philippines, Australia, Fiji, And American Samoa Using Baited Remote Underwater Video Systems, Gregory Jeff Barord, Frederick Dooley, Andrew Dunstan, Anthony Ilano, Karen N. Keister, Heike Neumeister, Thomas Preuss, Shane Schoepfer, Peter D. Ward

Publications and Research

The extant species of Nautilus and Allonautilus (Cephalopoda) inhabit fore-reef slope environments across a large geographic area of the tropical western Pacific and eastern Indian Oceans. While many aspects of their biology and behavior are now well-documented, uncertainties concerning their current populations and ecological role in the deeper, fore-reef slope environments remain. Given the historical to current day presence of nautilus fisheries at various locales across the Pacific and Indian Oceans, a comparative assessment of the current state of nautilus populations is critical to determine whether conservation measures are warranted. We used baited remote underwater video systems (BRUVS) to make …


Early Back-To-Africa Migration Into The Horn Of Africa, Jason A. Hodgson, Connie J. Mulligan, Ali Al-Meeri, Ryan L. Raaum 2014 Imperial College London

Early Back-To-Africa Migration Into The Horn Of Africa, Jason A. Hodgson, Connie J. Mulligan, Ali Al-Meeri, Ryan L. Raaum

Publications and Research

Genetic studies have identified substantial non-African admixture in the Horn of Africa (HOA). In the most recent genomic studies, this non-African ancestry has been attributed to admixture with Middle Eastern populations during the last few thousand years. However, mitochondrial and Y chromosome data are suggestive of earlier episodes of admixture. To investigate this further, we generated new genome-wide SNP data for a Yemeni population sample and merged these new data with published genome-wide genetic data from the HOA and a broad selection of surrounding populations. We used multidimensional scaling and ADMIXTURE methods in an exploratory data analysis to develop hypotheses …


The Effect Of Population History On Hominoid Intraspecific Cranial Shape Diversity: Combining Population Genetic And 3d Geometric Morphometric Data, Julia Marie Zichello 2014 CUNY Graduate Center

The Effect Of Population History On Hominoid Intraspecific Cranial Shape Diversity: Combining Population Genetic And 3d Geometric Morphometric Data, Julia Marie Zichello

Dissertations, Theses, and Capstone Projects

Cranial shape diversity within hominoids has been previously studied with the aim of understanding how levels of diversity in extant species compare with extinct hominin specimens. This dissertation addresses the question of why cranial shape diversity differs among extant hominoids. Levels of intraspecific cranial shape diversity are highly varied among hominoids. For example, Sumatran orangutan cranial shape diversity is more than twice that of all living humans. Here, the population history of each species, or sub-species, is considered as a force potentially structuring phenotypic variation. It is already well established that population history has shaped patterns of modern human cranial …


Early Song Discrimination By Nestling Sparrows In The Wild, Daizaburo Shizuka 2014 University of Nebraska-Lincoln

Early Song Discrimination By Nestling Sparrows In The Wild, Daizaburo Shizuka

School of Biological Sciences: Faculty Publications

Songs play an important role in premating isolation in birds. However, when songs are learned, expe- rience with both conspecific and heterospecific songs in early life could lead to the development of both mixed songs and mixed preferences. One way that such learning errors can be prevented is if birds can discriminate between songs of different species prior to learning and preferentially memorize conspe- cific songs. Prior captive studies have shown that white-crowned sparrows, Zonotrichia leucophrys, are able to discriminate songs early in the process of song memorization, after about 10 days since hatching. I studied early song discrimination in …


Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher 2014 California Polytechnic State University, San Luis Obispo

Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher

Master's Theses

  • Climate change models predict an increase in frequency and amplitude of extreme weather events, including heat waves. To better predict how the composition and distribution of plant assemblages might respond to these changes in temperature, it is important to understand how species currently respond to these extremes. Photosynthetic thermal tolerance (T25)and photosynthetic recovery (RT25) were quantified in 27 species. We also studied the relationships between T25, RT25 and leaf mass per area (LMA). Leaf temperature was also monitored in the field.
  • Leaves used in this study were collected from two distinct …


The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, Anne-Lise Ducluzeau, Barbara Schoepp-Cothenet, Robert van Lis, Frauke Baymann, Michael J. Russell, Wilfgang Nitschke 2014 University of Nebraska-Lincoln

The Evolution Of Respiratory O2/No Reductases: An Out-Of-The-Phylogenetic-Box Perspective, Anne-Lise Ducluzeau, Barbara Schoepp-Cothenet, Robert Van Lis, Frauke Baymann, Michael J. Russell, Wilfgang Nitschke

Department of Biochemistry: Faculty Publications

Complex life on our planet crucially depends on strong redox disequilibria afforded by the almost ubiquitous presence of highly oxidizing molecular oxygen. However, the history of O2-levels in the atmosphere is complex and prior to the Great Oxidation Event some 2.3 billion years ago, the amount of O2 in the biosphere is considered to have been extremely low as compared with present-day values. Therefore the evolutionary histories of life and of O2-levels are likely intricately intertwined. The obvious biological proxy for inferring the impact of changing O2-levels on life is the evolutionary history …


Joint Phenotypes, Evolutionary Conflict And The Fundamental Theorem Of Natural Selection, David C. Queller 2014 Washington University in St Louis

Joint Phenotypes, Evolutionary Conflict And The Fundamental Theorem Of Natural Selection, David C. Queller

Biology Faculty Research

Multiple organisms can sometimes affect a common phenotype. For example, the portion of a leaf eaten by an insect is a joint phenotype of the plant and insect and the amount of food obtained by an offspring can be a joint trait with its mother. Here, I describe the evolution of joint phenotypes in quantitative genetic terms. A joint phenotype for multiple species evolves as the sum of additive genetic variances in each species, weighted by the selection on each species. Selective conflict between the interactants occurs when selection takes opposite signs on the joint phenotype. The mean fitness of …


A Male Spider’S Ornamentation Polymorphism Maintained By Opposing Selection With Two Niches, Bo Deng, Alex Estes, Brett Grieb, Douglas Richard, Brittney Hinds, Eileen Hebets 2014 University of Nebraska-Lincoln

A Male Spider’S Ornamentation Polymorphism Maintained By Opposing Selection With Two Niches, Bo Deng, Alex Estes, Brett Grieb, Douglas Richard, Brittney Hinds, Eileen Hebets

Eileen Hebets Publications

The Levene mechanism to maintain genotypic polymorphism by opposing selection on genotypes in multiple niches was proposed 60 years ago, and yet no systems were found to satisfy the mechanisms rather restrictive conditions. Reported here is such an example that a wolf spider population lives in a habitat of mixed rocks and leafy litter for which the females are phenotypically indistinguishable and the males have two distinct phenotypes subject to opposing selection with respect to the substrates. Census data is best-fitted to a population genetics model of the Levene type. A majority of the best fit support polymorphism, with many …


Pelargonium (Geraniaceae) And The Long-Tongued Fly Pollination Guild: Coevolution And Polymorphism In A Specialized Pollination System, Emily M. Blank 2014 University of Connecticut - Storrs

Pelargonium (Geraniaceae) And The Long-Tongued Fly Pollination Guild: Coevolution And Polymorphism In A Specialized Pollination System, Emily M. Blank

Honors Scholar Theses

In South Africa, a group of long-tongued flies and the flowering plants they pollinate form a unique and diverse pollination guild system almost entirely endemic to the Greater Cape Floristic Region. This system makes up only a small portion of the biodiversity of the Region, but it is likely a key to understanding the evolutionary processes that have lead to the observed biodiversity. Aside from its unusual pollinators, this guild system is of particular interest due to the extremely labile morphology of both the fly species and the associated flowering plant species, which geographically vary significantly in proboscis lengths and …


Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr 2014 East Tennessee State University

Inter-And Intra-Population Variability Across The Transcriptome Of Lake Baikal’S Endemic Copepod With Ramifications For Adapting To Climate Change, Larry L. Bowman Jr

Electronic Theses and Dissertations

The future of Lake Baikal’s biodiversity is uncertain in response to climate change. Unlike its diverse benthos, Lake Baikal’s zooplankton is species poor, with up to 96% of its biomass being composed of a single Calanoid copepod species, Epischura baikalensis. This study characterizes the genetic differentiation and differential gene expression of E. baikalensis. Using partial-transcriptome sequences obtained by 454 Rosche and Illumina sequencing technologies, the genetic differentiation at inferred single nucleotide polymorphism (SNP) sites and differential gene expression in populations sampled from various parts of the lake were analyzed. The functional genomics of genes showed significant differential …


Evolutionary Pressures On Primate Intertemporal Choice, Jeffrey R. Stevens 2014 University of Nebraska-Lincoln

Evolutionary Pressures On Primate Intertemporal Choice, Jeffrey R. Stevens

Department of Psychology: Faculty Publications

From finding food to choosing mates, animals must make intertemporal choices that involve fitness benefits available at different times. Species vary dramatically in their willingness to wait for delayed rewards. Why does this variation across species exist? An adaptive approach to intertemporal choice suggests that time preferences should reflect the temporal problems faced in a species' environment. Here, I use phylogenetic regression to test whether allometric factors (relating to body size), relative brain size, and social group size predict how long 13 primate species will wait in laboratory intertemporal choice tasks. Controlling for phylogeny, a composite allometric factor that includes …


Transcriptomic Insights Into The Diplontic Life History Of Diatoms, Colton Richard Kessenich 2014 University of Arkansas, Fayetteville

Transcriptomic Insights Into The Diplontic Life History Of Diatoms, Colton Richard Kessenich

Graduate Theses and Dissertations

An organism's life cycle is the direct result of its evolutionary history and represents a fundamental aspect of its ancestry and ecology. Yet the process of linking alternating life-history stages has proven to be challenging, if not impossible in some cases. Diatoms (Bacillariophyceae) are no exception to this challenge, and their diversity of life stages and reproductive strategies add further challenges. A central focus of diatom research has been to unravel the evolutionary events that led to their extraordinary diversity, a line of inquiry that has been greatly aided by the availability of next-generation sequence data. Yet without proper taxonomic …


Body Size And Species Richness Changes In Glyptosaurinae (Squamata: Anguidae) Through Climatic Transitions Of The North American Cenozoic, Sara ElShafie 2014 University of Nebraska-Lincoln

Body Size And Species Richness Changes In Glyptosaurinae (Squamata: Anguidae) Through Climatic Transitions Of The North American Cenozoic, Sara Elshafie

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Poikilothermic vertebrates offer excellent climate proxies based on relationships between environment and measurable variables such as body size and species richness. Relationships of these variables in lizards to environmental transitions over long time scales are poorly understood. Here I show that patterns of body size and species richness in a lizard clade, Glyptosaurinae (Squamata: Anguidae), correspond to known histories of paleotemperatures through the Cenozoic of North America. Glyptosaurines have the richest fossil record among North American Cenozoic lizards and exhibit a wide range of skull sizes. In order to estimate body size for glyptosaurines and other fossil anguids, I collected …


Fossil Crocodilians From The High Guajira Peninsula Of Colombia, And The History Of Neogene Crocodilian Diversity In Tropical South America, Jorge W. Moreno-Bernal 2014 University of Nebraska-Lincoln

Fossil Crocodilians From The High Guajira Peninsula Of Colombia, And The History Of Neogene Crocodilian Diversity In Tropical South America, Jorge W. Moreno-Bernal

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The greatest diversity of Cenozoic crocodilians occurred during the Miocene in equatorial South America. However, the origin of this high diversity and its relationship to environmental factors are poorly understood. Most described species come from localities assigned to Laventan (13.8-11.8 Ma) and Huayquerian (9.0-6.8 Ma) South American land mammal ages (SALMAS), whereas the record is sparse in the early to middle Miocene and after the latest Miocene and Pliocene. Field research in the Castilletes (early Miocene-Pliocene) Formation in the High Guajira Peninsula of Colombia provides new fossil data on the origin of Neotropical crocodylian diversity. The Castilletes Formation crops out …


Evolutionary Change In Continuous Reaction Norms, Courtney J. Murren, Heidi J. Maclean, Sarah E. Diamond, Ulrich K. Steiner, Mary A. Heskel, Corey A. Handelsman, Cameron K. Ghalambor, Josh R. Auld, Hilary S. Callahan, David W. Pfennig, Rick A. Relyea, Carl D. Schlichting, Joel Kingsolver 2014 College of Charleston

Evolutionary Change In Continuous Reaction Norms, Courtney J. Murren, Heidi J. Maclean, Sarah E. Diamond, Ulrich K. Steiner, Mary A. Heskel, Corey A. Handelsman, Cameron K. Ghalambor, Josh R. Auld, Hilary S. Callahan, David W. Pfennig, Rick A. Relyea, Carl D. Schlichting, Joel Kingsolver

Biology Faculty Publications

No abstract provided.


A Phylogenetic Reevaluation Of The Genus Gavia (Aves: Gaviiformes) Using Next-Generation Sequencing, Quentin D. Sprengelmeyer 2014 Northern Michigan University

A Phylogenetic Reevaluation Of The Genus Gavia (Aves: Gaviiformes) Using Next-Generation Sequencing, Quentin D. Sprengelmeyer

All NMU Master's Theses

Avian phylogenetic analysis based on DNA sequences, rather than morphological characters, has been used in recent decades to resolve systematic relationships. Advancements in molecular techniques have improved avian phylogenetics and have led to new insights on the relationships between and within taxa. Loons (Aves: Gaviiformes) are one of the oldest living lineages of birds, and the order includes five extant species. The morphological cladogram of Gavia placed G. arctica as a sister species to G. pacifica. However, a more recent study based on mtDNA resulted in a discordant tree splitting the G. arctica/G. pacifica clade, and …


Stress Responses And Energy Storage In Drosophila Melanogaster Selected For Resistance To A Gram-Positive Bacillus Cereus Spores, Zhen Hu 2014 University of Nebraska-Lincoln

Stress Responses And Energy Storage In Drosophila Melanogaster Selected For Resistance To A Gram-Positive Bacillus Cereus Spores, Zhen Hu

School of Biological Sciences: Dissertations, Theses, and Student Research

A survival response study was carried out by using D. melanogaster and the opportunistic pathogen B. cereus as the agent of selection. The spores of B. cereus, a gram-positive bacteria that can cause the human pathogen disease, were applied in our artificial laboratory selection. Selected lines were treated with B. cereus spores. Wound control lines were punctured with a needle dipped into sterile H2O. Control lines did not apply any treatment. Three different environmental treatments were used within each line type (autoclaved spores of B.cereus, sterile H2O and no treatment). The autoclaved spores were …


Pathways Of Embodiment: Drug Use Among Adolescents In Popay[Aacute]N Colombia, Sarah Louise Fishleder 2014 University of South Florida

Pathways Of Embodiment: Drug Use Among Adolescents In Popay[Aacute]N Colombia, Sarah Louise Fishleder

USF Tampa Graduate Theses and Dissertations

This research examines the interrelated biological and cultural factors that determine pathways by which recreational drug use is manifest to addiction in the lives of youth aged 12-18 in Popay[aacute]n, Colombia. It utilizes existing data from mixed methods research conducted between 2004-2005 examining epidemiological risk factors, drug use, perceptions about drugs, and a biological phenomenon of the brain known as incentive salience. Perceptions and experiences related to drugs were gathered using structured methods. MDS and hierarchical plots of drug perceptions are presented in order to demonstrate the power of culture and expectation on perception and choice. Structural equation modeling was …


Conservative Evolution, Sustainability, And Culture, Gábor Náray-Szabó 2014 Eötvös Loránd University

Conservative Evolution, Sustainability, And Culture, Gábor Náray-Szabó

CLCWeb: Comparative Literature and Culture

In his article "Conservative Evolution, Sustainability, and Culture" Gábor Náray-Szabó argues that evolution is conservative in the sense that throughout the history of the universe old constructs like elementary particles, amino acids, and living cells remained conserved while the world evolved/evolves in complexity. A similar process can be observed in cultural evolution as components of society and culture continue to evolve. Considering the increasing pressure on natural resources by material consumption, a close alliance between past, present, and future generations is unavoidable and thus Náray-Szabó posits that concepts of conservative evolution and sustainability are related. However, in order to avoid …


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