Genetics and Genomics Commons^™

The Distribution Of Fitness Effects Of Spontaneous Mutations In Vibrio Fischeri, Chelsea K. Jones

Honors Theses and Capstones

Mutations are the ultimate source of the biological diversity on which natural selection acts, but the vast majority of these mutations are harmful. As such, mutations lead to disease states like cancer, extinction of small populations, and can drive pathogen evolution. Unfortunately, because mutations are rare and past studies have been subject to detection biases, very little is known about the distribution of fitness effects from naturally occurring mutations. In this study, we used mutation accumulation and full genome sequencing to capture naturally occurring mutations before they were exposed to the sieve of natural selection in Vibrio fischeri. We …

The Prevalence And Effect Of Wolbachia Infection On The Brown Widow Spider (Latrodectus Geometricus), Brittany Dane' Arrington

College of Graduate Studies: Theses & Dissertations

Wolbachia was recently identified in the Brown Widow Spider (Latrodectus geometricus). This symbiont has not previously been found in this genus, therefore the consequences on the host’s population dynamics are unknown. The frequency of endosymbiont infection can provide insight into the population dynamics of the host as this bacteria is known to alter host life history. In my 1^st chapter I determine the prevalence of Wolbachia pipentis infection in in the Brown Widow Spider (Latrodectus geometricus) from five locations in the Southeastern United States. Infection frequency differed significantly among sampling locations, ranging from 20% to …

Hidden Diversity In Sardines: Genetic And Morphological Evidence For Cryptic Species In The Goldstripe Sardinella, Sardinella Gibbosa (Bleeker, 1849), Rey C. Thomas, Demian A. Willette, Kent E. Carpenter, Mudjekeewis D. Santos

Biological Sciences Faculty Publications

Cryptic species continue to be uncovered in many fish taxa, posing challenges for fisheries conservation and management. In Sardinella gibbosa, previous investigations revealed subtle intra-species variations, resulting in numerous synonyms and a controversial taxonomy for this sardine. Here, we tested for cryptic diversity within S. gibbosa using genetic data from two mitochondrial and one nuclear gene regions of 248 individuals of S. gibbosa, collected from eight locations across the Philippine archipelago. Deep genetic divergence and subsequent clustering was consistent across both mitochondrial and nuclear markers. Clade distribution is geographically limited: Clade 1 is widely distributed in the central Philippines, while …

Epistasis In Predator-Prey Relationships, Iuliia Inozemtseva

College of Graduate Studies: Theses & Dissertations

Epistasis is the interaction between two or more genes to control a single phenotype. We model epistasis of the prey in a two-locus two-allele problem in a basic predator- prey relationship. The resulting model allows us to examine both population sizes as well as genotypic and phenotypic frequencies. In the context of several numerical examples, we show that if epistasis results in an undesirable or desirable phenotype in the prey by making the particular genotype more or less susceptible to the predator or dangerous to the predator, elimination of undesirable phenotypes and then genotypes occurs.

Endogenous Ros Levels In C. Elegans Under Exogenous Stress Support Revision Of Oxidative Stress Theory Of Life-History Tradeoffs, Samson W. Smith, Leigh C. Latta Iv, Dee R. Denver, Suzanne Estes

Biology Faculty Publications and Presentations

Background: The oxidative stress theory of life-history tradeoffs states that oxidative stress caused by damaging free radicals directly underpins tradeoffs between reproduction and longevity by altering the allocation of energetic resources between these tasks. We test this theory by characterizing the effects of exogenous oxidative insult and its interaction with thermal stress and diet quality on a suite of life-history traits and correlations in Caenorhabditis elegans nematodes. We also quantify demographic aging rates and endogenous reactive oxygen species (ROS) levels in live animals.

Results: Our findings indicate a tradeoff between investment in reproduction and antioxidant defense (somatic maintenance) consistent with …

Nocturnal Homing In The Tropical Amblypygid Phrynus Pseudoparvulus (Class Arachnida, Order Amblypygi), Eileen Hebets, E.J. Gering, Verner P. Bingman, Daniel D. Wiegmann

Eileen Hebets Publications

Arthropods are renowned for their navigational capabilities, with numerous examples known from insects and crustaceans. Early studies of amblypygids (Class Arachnida, Order Amblypygi) also suggest complex nocturnal navigation, despite their apparent lack of visual adaptations to the low-light conditions of a tropical understory. In a series of two studies, we use the tropical amblypygid, Phrynus pseudoparvulus, to assess their nocturnal homing ability. Our first experiment displaced and tracked resident and nonresident individuals. Resident individuals, displaced up to 4.5 m from their home refuges and released onto their home tree, were more likely to return to their previously occupied refuge than …

Detection Of Predator Cues Alters Mating Tactics In Male Wolf Spiders, Dustin J. Wilgers, Daniel Wickwire, Eileen Hebets

Eileen Hebets Publications

Males of the wolf spider, Rabidosa punctulata, exhibit condition-dependent alternative mating tactics, whereby small, poor condition males engage in multimodal courtship while large, good condition males adopt a direct mount tactic that forgoes courtship. This study explores the possibility that tactic-specific costs can help explain this unintuitive pattern of mating tactic expression. Specifically, we hypothesize that courtship signaling is costly with respect to eavesdropping by predators and that males can alter their tactic expression based upon the perceived environmental predation risk. We test this by first examining the risk of predation associated with different mating tactics. We use a …

Recognition Of Two New Species Of Freshwater Crabs From The Seychelles Based On Molecular Evidence (Potamoidea: Potamonautidae)., Neil Cumberlidge, Savel Regan Daniels Phd

Journal Articles

The Afrotropical freshwater crab genus Seychellum is endemic to the granitic Seychelles in the Indian Ocean (Mahé, Silhouette, Praslin, La Digue and Frégate). Here we describe two new cryptic species of Seychellum that represent two evolutionarily separate lineages of a previously monotypic genus. This raises to three the number of species of freshwater crabs known from Seychelles. Each species is endemic to either one island (Silhouette) or to a pair of islands (Mahé and Frégate, or Praslin and La Digue). The three species can be clearly distinguished as separate lineages by DNA analysis, haplotyping and examination of gonopod characters. The …

Lineage-Specific Transcriptional Profiles Of Symbiodinium Spp. Unaltered By Heat Stress In A Coral Host, Daniel J. Barshis, Jason T. Ladner, Thomas A. Oliver, Stephen R. Palumbi

Biological Sciences Faculty Publications

Dinoflagellates of the genus Symbiodinium form an endosymbiosis with reef building corals, in which photosynthetically derived nutrients comprise the majority of the coral energy budget. An extraordinary amount of functional and genetic diversity is contained within the coral-associated Symbiodinium, with some phylotypes (i.e., genotypic groupings), conferring enhanced stress tolerance to host corals. Recent advances in DNA sequencing technologies have enabled transcriptome-wide profiling of the stress response of the cnidarian coral host; however, a comprehensive understanding of the molecular response to stress of coral-associated Symbiodinium, as well as differences among physiologically susceptible and tolerant types, remains largely unexplored. Here, …

Determining Parentage And The Effects Of Relatedness On Play Partner Preference In Belding's Ground Squirrels, Jessica Weidenbach

Master's Theses

I investigated 1) multiple paternity in Belding’s ground squirrels (Urocitellus beldingi) and 2) social partner preferences in juvenile U. beldingi. Prior work with blood allozymes demonstrated multiple paternity in U. beldingi litters. I evaluated paternity using microsatellite DNA analysis, which is more accurate than examining blood allozymes. My results indicate that multiple paternity in U. beldingi is more extensive than previously shown, occurring in about 90% of litters with more than one juvenile, and averaging 2.95 fathers in multiply sired litters. I also evaluated the hypothesis that play and other social behavior promotes bonding among juvenile female …

Time-Dependent Random Effect Poisson Random Field Model For Polymorphism Within And Between Two Related Species, Shilei Zhou

UNLV Theses, Dissertations, Professional Papers, and Capstones

Molecular evolution is partially driven by mutation, selection, random genetic drift, or combination of the three factors. To quantify the magnitude of these genetic forces, a previously developed time-dependent fixed effect Poisson random field model provides powerful likelihood and Bayesian estimates of mutation rate, selection coefficient, and species divergence time. The assumption of the fixed effect model that selection intensity is constant within a genetic locus but varies across genes is obviously biologically unrealistic, but it serves the original purpose of making statistical inference about selection and divergence between two related species they are individually at mutation-selection-drift inequilibrium. By relaxing …

The Roles Of Phenotypic Plasticity And Genotypic Specialization In High Altitude Adaptation, Danielle M. Tufts

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

In vertebrates living at high altitude, arterial hypoxemia may be ameliorated by reversible changes in the oxygen-carrying capacity of the blood (regulated by erythropoiesis) and/or changes in blood–oxygen affinity (regulated by allosteric effectors of hemoglobin function). These hematological traits often differ between taxa that are native to different elevational zones, but it is often unknown whether the observed physiological differences reflect fixed, genetically based differences or environmentally induced acclimatization responses (phenotypic plasticity). Here, we report measurements of hematological traits related to blood–O₂ transport in populations of deer mice (Peromyscus maniculatus) that are native to high- and low-altitude …

The Genetic Architecture Of Juvenile Migration In Rainbow Trout (Oncorhynchus Mykiss), Benjamin Charles Hecht

Open Access Dissertations

Animal migrations play a critical role in the health and balance of ecological systems and in the evolution and diversification of species, and this is perhaps best displayed amongst salmonid fishes (salmon, trout, and char) who exhibit variation in the propensity to migrate both within and among species. Rainbow and steelhead trout (Oncorhynchus mykiss), members of the salmonid family of fishes, capture this variation throughout their native range. Some populations and ecotypes will remain resident in freshwater habitats throughout their life history; while others have the ability to embark on tremendous marine migrations. Those that migrate undergo a suite of …

Analysis Of Uniparental Lineages In Two Villages Of Santiago Del Estero, Argentina, Seat Of “Pueblos De Indios” In Colonial Times, Maia Pauro, Angelina García, Rodrigo Nores, Darío A. Demarchi

Human Biology Open Access Pre-Prints

Based on the analysis of the mitochondrial control region and seven biallelic markers of the Y Chromosome, we investigated the genetic composition of two rural populations of southern Santiago del Estero, Argentina, that were seats in colonial times of “pueblos de indios”, a colonial practice that consisted of concentrating the indigenous populations in organized and accessible settlements, to facilitate Christianizing and policing. We found the Native American Y chromosome haplogroup Q1a3a in only 11% (3/27) of the males. Haplogroup R, common in European populations, is the most frequent haplogroup in Santiago del Estero (55%). In contrast, the persistence of Native …

Genetic Variation Of X-Strs In The Wichí Population From Chaco Province, Argentina, Laura Angela Glesmann, Pablo Francisco Martina, Cecilia Inés Catanesi

Human Biology Open Access Pre-Prints

The Wichí people from Chaco province inhabit the region called Impenetrable Chaqueño, where the climatic conditions are extreme. Besides the scarce communication with the main urban centers, the cultural patterns of the Wichí cause these communities to live in certain degree of isolation. The effect of this situation is an increased genetic differentiation from other populations, as it was observed through autosomal and Y chromosome markers. However, the genetic variation of X chromosome has not been fully analyzed yet. The patterns of allele distribution of different markers of X chromosome can be highly informative in comparative studies, because its special …

Signatures Of Rapid Evolution In Urban And Rural Transcriptomes Of White-Footed Mice (Peromyscus Leucopus) In The New York Metropolitan Area, Stephen Edward Harris, Jason Munshi-South, Craig Oberfell, Rachel O'Neill

Publications and Research

Urbanization is a major cause of ecological degradation around the world, and human settlement in large cities is accelerating. New York City (NYC) is one of the oldest and most urbanized cities in North America, but still maintains 20% vegetation cover and substantial populations of some native wildlife. The white-footed mouse, Peromyscus leucopus, is a common resident of NYC’s forest fragments and an emerging model system for examining the evolutionary consequences of urbanization. In this study, we developed transcriptomic resources for urban P. leucopus to examine evolutionary changes in protein-coding regions for an exemplar “urban adapter.” We used Roche 454 …

Elk (Cervus Elaphus) Seasonal Habitat Selection In A Heterogeneous Forest Structure, Jesse N. Popp, David N.C. Mcgeachy, Josef Hamr

Aspen Bibliography

Seasonal habitat selection by the reintroduced Burwash elk population, approximately 30 km south of Sudbury, Ontario, has been analysed in order to assist in the development of future management. Twenty-five adult females were radio-collared and tracked 1–3 times a week for 3 years. The most prominent patterns included selection of intolerant hardwood forests (trembling aspen, white birch, and balsam poplar) during all seasons, while Great Lakes-St. Lawrence pines (white and red pine dominated stands) were used less than expected based on availability for all seasons. The selection patterns are likely associated with seasonal climatic conditions and forage preferences. Because the …

The Rate And Effects Of Spontaneous Mutation On Fitness Traits In The Social Amoeba, Dictyostelium Discoideum, David W. Hall, Sara Fox, Jennie J. Kuzdzal-Fick, Joan E. Strassmann, David C. Queller

Biology Faculty Research

We performed a mutation accumulation (MA) experiment in the social amoeba Dictyostelium discoideum to estimate the rate and distribution of effects of spontaneous mutations affecting eight putative fitness traits. We found that the per-generation mutation rate for most fitness components is 0.0019 mutations per haploid genome per generation or larger. This rate is an order of magnitude higher than estimates for fitness components in the unicellular eukaryote Saccharomyces cerevisiae, even though the base-pair substitution rate is two orders of magnitude lower. The high rate of fitness-altering mutations observed in this species may be partially explained by a large mutational target …

A Comprehensive And Integrative Reconstruction Of Evolutionary History For Anomura (Crustacea: Decapoda)., Heather D Bracken-Grissom, Maren E Cannon, Patricia Cabezas, Rodney M Feldmann, Carrie E Schweitzer, Shane T Ahyong, Darryl L Felder, Rafael Lemaitre, Keith A Crandall

Computational Biology Institute

BACKGROUND: The infraorder Anomura has long captivated the attention of evolutionary biologists due to its impressive morphological diversity and ecological adaptations. To date, 2500 extant species have been described but phylogenetic relationships at high taxonomic levels remain unresolved. Here, we reconstruct the evolutionary history-phylogeny, divergence times, character evolution and diversification-of this speciose clade. For this purpose, we sequenced two mitochondrial (16S and 12S) and three nuclear (H3, 18S and 28S) markers for 19 of the 20 extant families, using traditional Sanger and next-generation 454 sequencing methods. Molecular data were combined with 156 morphological characters in order to estimate the largest …

Evolution Of A Higher Intracellular Oxidizing Environment In Caenorhabditis Elegans Under Relaxed Selection, Joanna Joyner-Matos, Kiley A. Hicks, Dustin Cousins, Michelle Keller, Dee R. Denver, Charles F. Baer, Suzanne Estes

Biology Faculty Publications and Presentations

We explored the relationship between relaxed selection, oxidative stress, and spontaneous mutation in a set of mutationaccumulation (MA) lines of the nematode Caenorhabditis elegans and in their common ancestor. We measured steady-state levels of free radicals and oxidatively damaged guanosine nucleosides in the somatic tissues of five MA lines for which nuclear genome base substitution and GC-TA transversion frequencies are known. The two markers of oxidative stress are highly correlated and are elevated in the MA lines relative to the ancestor; point estimates of the per-generation rate of mutational decay (DM) of these measures of oxidative stress are similar to …

Dna From Feces And Museum Specimens Confirms A First State Record Bird, Alec R. Lindsay Ph. D., Skye C. Haas

Faculty Works

In October 2005, a vagrant kingbird (Aves: Tyrannus sp.) appeared in Michigan’s Upper Peninsula, nearly 2000 km from the northern limit of its usual range. Using mitochondrial DNA obtained from a fecal sample deposited by the bird and mitochondrial DNA isolated from museum reference specimens, the species iden- tity of this bird was definitively confirmed as a Tropical Kingbird (T. melancholicus) rather than a Couch’s Kingbird (T. couchii). This is the first time DNA evidence has been used to establish a state bird record, and one of the few studies of any type to successfully use avian feces for DNA …

Occurrence And Genetic Diversity Of Lemon Sharks (Negaprion Brevirostris) At A Nursery Ground At The Chandeleur Islands, Louisiana., Jonathan F. Mckenzie

LSU New Orleans Theses and Dissertations

Anecdotal evidence suggested that immature lemon sharks (Negaprion brevirostris) occur at the Chandeleur Islands in southeastern Louisiana. From May 2009 to August 2011, the Nekton Research Laboratory at the University of New Orleans regularly sampled habitats at the Chandeleur Islands to confirm the presence of immature individuals of this species. During these efforts, 147 immature lemon sharks (neonates, young-of-the-year, and juveniles) were collected. Each shark was PIT tagged and a tissue sample was taken for genetic analyses. Sizes ranged from 56 – 177 cm total length. Sharks showed a preference for sandy substrate and smaller individuals showed significant preference …

Can Long-Range Pcr Be Used To Amplify Genetically Divergent Mitochondrial Genomes For Comparative Phylogenetics? A Case Study Within Spiders (Arthropoda: Araneae), Andrew G. Briscoe, Sara Goodacre, Susan E. Masta, Martin I. Taylor, Miquel A. Arnedo, David Penny, John Kenny, Simon Creer

Biology Faculty Publications and Presentations

The development of second generation sequencing technology has resulted in the rapid production of large volumes of sequence data for relatively little cost, thereby substantially increasing the quantity of data available for phylogenetic studies. Despite these technological advances, assembling longer sequences, such as that of entire mitochondrial genomes, has not been straightforward. Existing studies have been limited to using only incomplete or nominally intra-specific datasets resulting in a bottleneck between mitogenome amplification and downstream high-throughput sequencing. Here we assess the effectiveness of a wide range of targeted long-range PCR strategies, encapsulating single and dual fragment primer design approaches to provide …

Parentage Analysis And Conservation Genetics Educational Material For The Eastern Hellbender Salamander, Cryptobranchus Alleganiensis Alleganiensis, Sarah A. Chudyk

Master's Projects

Populations of the Eastern hellbender salamander, Cryptobranchus alleganiensis alleganiensis, are declining, making this a species of special concern in New York State and under consideration for Federal Endangered Species listing. As a result of this decline, the New York State Department of Environmental Conservation and the Buffalo Zoo initiated a headstarting program with an egg mass found in the Allegheny River drainage. The juveniles being raised by the Zoo will be released back into the watershed and so understanding the genetic diversity and parentage of these hellbenders will inform the reintroduction efforts. Furthermore, in order to determine how to …

Characterization Of Aebp2 Mutant Mice, Arundhati Bakshi

Honors Capstones

No abstract provided.

Genetic Structure Of The Copperhead (Viperidae: Agkistrodon Contortrix Mokasen) At Its Most Northern Distribution, Brenna Aaren Levine

Graduate Theses and Dissertations

The focus of molecular studies in North American pitvipers has been on species that warrant conservation concern, such as Timber (Crotalus horridus) and Massasauga rattlesnakes (Sistrurus catenatus). Scant effort has been directed towards the molecular ecology of the Copperhead (Agkistrodon contortrix), other than to evaluate male reproduction in a laboratory setting and phylogenetic history. Thus, employing DNA-based molecular techniques to study the natural history of A. contortrix will broaden our knowledge of molecular ecology in North American pitvipers, and particularly in a non-threatened species that can serve as a surrogate for threatened and endangered …

Characterization Of Resistance To The Cry1f Toxin From Bacillus Thuringiensis In Resistant Fall Armyworm, Spodoptera Frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) From Puerto Rico, Ana Maria Velez

Department of Entomology: Dissertations, Theses, and Student Research

Transgenic corn expressing Cry1F protein from Bacillus thuringiensis Berliner has been registered for Spodoptera frugiperda control since 2003. Unexpected damage to Cry1F corn was reported in 2006 in Puerto Rico and Cry1F resistance in S. frugiperda was documented. The inheritance of Cry1F resistance was characterized in a S. frugiperda resistant strain from Puerto Rico which displayed >387-fold resistance to Cry1F. Concentration-response bioassays of reciprocal crosses of resistant and susceptible parental populations indicated that resistance is recessive and autosomal. Bioassays of the backcross of the F₁ generation crossed with the resistant parental strain suggest that a single locus is responsible …

The Advertisement Calls And Distribution Of Two Sympatric Species Of Chiasmocleis (Méhely 1904) (Anura, Microhylidae, Gastrophryninae) From The Atlantic Forest, Mauricio C. Florani, Caio Vinicus De Mira Mendes, Iuri Ribeiro Dias, Danilo Silva Ruas, João Fillipe Riva Tonini, Rafael O. De Sá

Biology Faculty Publications

The advertisement calls of Chiasmocleis cordeiroi and C. crucis are described for populations from the municipalities of Igrapiúna and Camacan, respectively, state of Bahia, Brazil. Both calls consist of multipulsed notes produced in series. Differences between the two calls are: dominant frequency, higher in C. cordeiroi (range 4500–4898 Hz; C. crucis range 4069–4435 Hz); note rate, higher in C. cordeiroi (range 6.20–7.46 s/note; C. crucis range 5.17–5.59 s/note); pulse rate, higher in C. cordeiroi (151.82–194.83 s/note; C. crucis range 125.30– 142.12 s/note); and the structure of the modulation patterns of the notes. Moreover, the advertisement calls of C. crucis and …

Reproductive Isolation In The Elegans-Group Of Caenorhabditis, Scott Everet Baird, Sara Rose Seibert

Biological Sciences Faculty Publications

Reproductive isolation is the basis of the Biological Species Definition and can be a driving force of speciation. Theoretical studies have provided models of how reproductive isolation can arise within individual species. Genetic tests of these models are limited to populations in which reproductive isolation is present but not complete. Here, reproductive isolation in the Elgans-Group of the nematode genus Caenorhabditis is reviewed. Pre-mating barriers, assortative fertilization and post-zygotic barriers all have been observed in this clade. In some combinations of species, fertile F1 hybrids can be obtained. Therefore, the Elegans-Group of Caenorhabditis is poised to become an important experimental …

Landscape Genetics Of Leaf-Toed Geckos In The Tropical Dry Forest Of Northern Mexico, Christopher Blair, Victor H. Jimenez-Arcos, Fausto R. Mendez De La Cruz, Robert W. Murphy

Publications and Research

Habitat fragmentation due to both natural and anthropogenic forces continues to threaten the evolution and maintenance of biological diversity. This is of particular concern in tropical regions that are experiencing elevated rates of habitat loss. Although less well-studied than tropical rain forests, tropical dry forests (TDF) contain an enormous diversity of species and continue to be threatened by anthropogenic activities including grazing and agriculture. However, little is known about the processes that shape genetic connectivity in species inhabiting TDF ecosystems. We adopt a landscape genetic approach to understanding functional connectivity for leaf-toed geckos (Phyllodactylus tuberculosus) at multiple sites …