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Genetics and Genomics

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Articles 61 - 90 of 365

Full-Text Articles in Population Biology

Gene Drives And The Consequences Of Over-Suppression, Cole Butler May 2022

Gene Drives And The Consequences Of Over-Suppression, Cole Butler

Biology and Medicine Through Mathematics Conference

No abstract provided.

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Analysis Of Water Quality And Fish Communities Of Crooked Creek, Tributary To The Allegheny River In Southwestern Pennsylvania, Katherine Stupar May 2022

Analysis Of Water Quality And Fish Communities Of Crooked Creek, Tributary To The Allegheny River In Southwestern Pennsylvania, Katherine Stupar

Electronic Theses and Dissertations

Crooked Creek is a tributary of the Allegheny River with a drainage area of 292 square miles. It has been historically affected by mine drainage pollution. Extensive cleanup and monitoring efforts by the Commonwealth of Pennsylvania and the U.S. Army Corps of Engineers (USACE) have taken place over the last four decades. Unconventional oil extraction, or fracking, presents an emerging threat to the water quality of this stream and the health of its fish communities. Here we perform an analysis of the Crooked Creek watershed utilizing backpack electrofishing, eDNA metabarcoding, and various methods of water quality analysis. Seven sites on …

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Microbial Diversity And Community Structure In Sediments Associated With The Seagrass (Thallassia Testudinum) In Apalachicola Bay, Florida, Rahma Ahmed, Thomas Mcelroy, Troy Mutchler Apr 2022

Microbial Diversity And Community Structure In Sediments Associated With The Seagrass (Thallassia Testudinum) In Apalachicola Bay, Florida, Rahma Ahmed, Thomas Mcelroy, Troy Mutchler

Symposium of Student Scholars

Seagrass is an angiosperm which provides many ecosystem services in coastal areas, such as providing food, shelter and nurseries for many species, and decreasing the impact of waves on shorelines. A global assessment reported that 29% of known seagrass meadows are in a state of decline due to the effects of human activity. Seagrass is commonly found in shallow marine waters where they form meadows containing a microbiome that plays an important role in providing nutrients for seagrass growth, though little is known about the microorganisms within the seagrass meadow sediments. Our project collected sediments from seagrass meadows and adjacent …

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Genetic Variation Of The Mitochondrial Dna Control Region Across Plains Bison Herds In Usa And Canada, Gaimi Davies, Blake Mccann, Lee Jones, Stefano Liccioli, Maria Cecilia Penedo, Igor V. Ovtchinnikov Mar 2022

Genetic Variation Of The Mitochondrial Dna Control Region Across Plains Bison Herds In Usa And Canada, Gaimi Davies, Blake Mccann, Lee Jones, Stefano Liccioli, Maria Cecilia Penedo, Igor V. Ovtchinnikov

Biology Faculty Publications

Once numbering in the tens of millions, bison (Bison bison) have faced a broad range of challenges over the past century, including genetic impacts from the population bottleneck in the 1800s, and significant loss and fragmentation of habitat resulting in little opportunity for population growth on remaining small, geographically isolated reserves. To identify best practices for bison stewardship against this backdrop, managers must understand the genetic composition of existing conservation herds. This study characterized 14 plains bison (Bison bison bison) herds managed by the U.S. Department of Interior and Parks Canada Agency based on complete mtDNA …

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Conservation Status Assessment Of The Egg-Mimic Darter (Percidae: Etheostoma Pseudovulatum) Using A Multi-Faceted Approach, Zachary L. Wolf, John W. Johansen, Rebecca E. Blanton Mar 2022

Conservation Status Assessment Of The Egg-Mimic Darter (Percidae: Etheostoma Pseudovulatum) Using A Multi-Faceted Approach, Zachary L. Wolf, John W. Johansen, Rebecca E. Blanton

Southeastern Fishes Council Proceedings

The imperiled Egg-mimic Darter (Etheostoma pseudovulatum) is a headwater-adapted fish restricted to an area less than 1000 km2 in Tennessee. It is found in only six tributaries of the Duck River and the large, mainstem of this system may act as a barrier to dispersal, restricting population connectivity. The only status assessment of this species was over two decades ago; genetic diversity and the degree of population connectivity have never been evaluated. We conducted a conservation status assessment using a multi-faceted approach to better inform conservation management plans, including examining its current distribution, assessing habitat quality, estimating …

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Florida Sand Skink And Blue-Tailed Mole Skink: Expanding Geographic Coverage Of Genetic Analysis For Conservation, Emma Simpson Jan 2022

Florida Sand Skink And Blue-Tailed Mole Skink: Expanding Geographic Coverage Of Genetic Analysis For Conservation, Emma Simpson

College of Graduate Studies: Theses & Dissertations

The Lake Wales Ridge is important scrub habitat that has been increasingly altered since the post-Columbian settlement in Florida. This loss of habitat has caused extreme anthropogenic fragmentation within the Lake Wales Ridge resulting in isolation among extant scrub patches. To expand the geographic scope of previous studies and answer questions concerning population connectivity, we characterized genetic diversity and differentiation using cytochrome-b and microsatellite genetic markers for two endemic skink species: the Florida Sand Skink (Plestiodon reynoldsi) and Blue-tailed Mole Skink (Plestiodon egregius lividus). Both species display historical isolation between central and southern Lake Wales Ridge …

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Degradation And Nitrogen Cycling In The Context Of Biodiversity-Ecosystem Function Relationships In The Inquiline Bacterial Community Of Darlingtonia Californica, Megan Teigen Jan 2022

Degradation And Nitrogen Cycling In The Context Of Biodiversity-Ecosystem Function Relationships In The Inquiline Bacterial Community Of Darlingtonia Californica, Megan Teigen

Cal Poly Humboldt theses and projects

Biodiversity-ecosystem function (BEF) research aims to explain how species and their environments interact with each other. Microbial communities engage in vital biogeochemical pathways in a variety of natural ecosystems, and yet there are large knowledge gaps about the specific metabolic pathways in which they are involved. Degradation specifically contributes to nitrogen cycling globally through the breakdown of large organic nitrogen compounds into small inorganic nitrogen that is necessary for the survival of many other organisms. In this study, I focused on the degradative function of the inquiline microbial communities found within the carnivorous pitcher plant, Darlingtonia californica. Darlingtonia grows in …

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Evaluating Population Genetic Structure And Potential Genomic Signals Of Natural Selection In A Migratory Songbird (Protonotaria Citrea), Tyler A. Hohenstein Jan 2022

Evaluating Population Genetic Structure And Potential Genomic Signals Of Natural Selection In A Migratory Songbird (Protonotaria Citrea), Tyler A. Hohenstein

Theses and Dissertations

In this study I attempted to further resolve the population genetic structure in the Prothonotary Warbler (Protonotaria citrea), and conducted an outlier SNP analysis and exploratory gene ontology analysis to investigate potential ongoing natural selection in the species. This analysis of population structure confirms previous work by DeSaix et al. (2019), where weak population structure was observed between eastern sites along the Atlantic Coastal Plain, and western sites in the Mississippi Alluvial Valley, possibly due to a genetic discontinuity across the Appalachian Mountains. I conducted two forms of outlier SNP analyses, a principal component analysis (PCA)-based approach to identify SNPs …

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Efficacy Of Non-Lethal Molecular Methods In Elucidating Distribution Of Gray Treefrog Complex (Hyla Chrysoscelis/Versicolor) In Kansas, Nora K. Lazerus Jan 2022

Efficacy Of Non-Lethal Molecular Methods In Elucidating Distribution Of Gray Treefrog Complex (Hyla Chrysoscelis/Versicolor) In Kansas, Nora K. Lazerus

Master's Theses or Doctor of Nursing Practice

Globally, amphibians are the most imperiled vertebrate taxa in part because they rely on both aquatic and terrestrial ecosystems. Specifically, their permeable skin makes them uniquely susceptible to habitat degradation and alteration. Cope’s Gray Treefrog (Hyla chrysoscelis) and the Gray Treefrog (Hyla versicolor) are a diploid-tetraploid, morphologically indistinguishable sister pair of cryptic anurans native to Kansas. Since 1987, the distribution of gray treefrogs in Kanas has extended west but the status of each species in the complex in Kansas is not known beyond its documented combined western expansion. Currently, species identification cannot be determined by nonlethal …

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Population Structure Of The Lizard Ecpleopus Gaudichaudii Coincides With A Biogeographic Barrier - The Doce River, Alexander J. Garretson Jan 2022

Population Structure Of The Lizard Ecpleopus Gaudichaudii Coincides With A Biogeographic Barrier - The Doce River, Alexander J. Garretson

Dissertations and Theses

Intraspecific genetic variation is an integral component of diversification and the accumulation of biodiversity. The degree to which isolated populations of the same species are genetically structured in geographical space is impacted by a variety of mechanisms. In this study, I document patterns and discuss possible drivers of genetic structure within Ecpleopus gaudichaudii, a lizard species endemic to the Atlantic Forest of Brazil. For that, I assembled ddRadseq sequences from 48 individuals across much of the range of the E. gaudichaudii and analyzed its population structure. I created an intraspecific phylogeny for this group utilizing RAxML and conducted a …

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Phylogenetic Origins And Age-Based Proportions Of Malacho (Elops Smithi) Relative To Ladyfish (Elops Saurus): Species On The Move In The Western Gulf Of Mexico, Damon Williford, Nicolette S. Beeken, Joel Anderson, Polly Hajovsky, Roberta Weixelman Jan 2022

Phylogenetic Origins And Age-Based Proportions Of Malacho (Elops Smithi) Relative To Ladyfish (Elops Saurus): Species On The Move In The Western Gulf Of Mexico, Damon Williford, Nicolette S. Beeken, Joel Anderson, Polly Hajovsky, Roberta Weixelman

Gulf and Caribbean Research

Two species of ladyfish occur in the Gulf of Mexico (GOM), Elops saurus and Elops smithi, that are morphologically indistinguishable except for vertebral counts but can also be identified by mitochondrial DNA haplotypes. Here we expand on previous work, most of which has occurred in Florida, and examine the demography, phylogenetics, geographic distribution, and age—structure of ladyfishes in Texas estuaries. Fishery—independent gill net data demonstrated that ladyfishes increase in abundance from north to south along the Texas coast. The abundance of ladyfishes also increased in Texas waters from 1982–2021, which coincides with recent trends of warmer winters. Genetic data …

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Population Genomics Of Redbreast Sunfish (Lepomis Auritus): Exploring Gene Flow And Local Adaptation In A Widely Distributed Freshwater Fish, Garret J. Strickland Jan 2022

Population Genomics Of Redbreast Sunfish (Lepomis Auritus): Exploring Gene Flow And Local Adaptation In A Widely Distributed Freshwater Fish, Garret J. Strickland

College of Graduate Studies: Theses & Dissertations

Little information is available concerning the distribution of genetic diversity in non-salmonid, non-imperiled, freshwater fish. In order to fill in this knowledge gap, I conducted a population genomics survey in Redbreast Sunfish (Lepomis auritus; RBS), a widespread, generalist species distributed along the Atlantic slope rivers of eastern North America. I sampled four basins (ACF, Savannah, Roanoke, and James) at eight sites each with a factorial experimental design. Sites were distributed among coastal plain, Piedmont, or mountain ecoregions in order to capture the greatest range of environmental states experienced by RBS, with the intention of finding evidence for local adaptation to …

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An Analysis Of The Spatial Genetic Structure Of A Hybrid Zone Between Two Species Of Killifish, Fundulus Heteroclitus And F. Grandis, Andrew Lee Hardy Jan 2022

An Analysis Of The Spatial Genetic Structure Of A Hybrid Zone Between Two Species Of Killifish, Fundulus Heteroclitus And F. Grandis, Andrew Lee Hardy

UNF Graduate Theses and Dissertations

Hybridization offers unique insight into the evolutionary process of speciation and the forces that maintain barriers to reproduction. In northeast Florida, a hybrid zone between two species of killifish, Fundulus heteroclitus and F. grandis, has been identified near Flagler Beach, FL, although the exact boundaries of the hybrid zone remain unknown (Gonzalez et al. 2009). This study aims to determine the fine-scale spatial genetic patterns of the hybrid zone and test the hypothesis that species ranges are influenced by changes in dominant vegetation. Results from an ADMIXTURE analysis and FST data indicated the boundary of the area of …

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Genome-Scale Data Reveal Deep Lineage Divergence And A Complex Demographic History In The Texas Horned Lizard (Phrynosoma Cornutum) Throughout The Southwestern And Central Us, Nicholas Finger, Keaka Farleigh, Jason T. Bracken, Adam D. Leaché, Olivier François, Ziheng Yang, Tomas Flouri, Tristan Charran, Tereza Jezkova, Dean A. Williams, Christopher Blair Nov 2021

Genome-Scale Data Reveal Deep Lineage Divergence And A Complex Demographic History In The Texas Horned Lizard (Phrynosoma Cornutum) Throughout The Southwestern And Central Us, Nicholas Finger, Keaka Farleigh, Jason T. Bracken, Adam D. Leaché, Olivier François, Ziheng Yang, Tomas Flouri, Tristan Charran, Tereza Jezkova, Dean A. Williams, Christopher Blair

Publications and Research

The southwestern and central US serve as an ideal region to test alternative hypotheses regarding biotic diversification. Genomic data can now be combined with sophisticated computational models to quantify the impacts of paleoclimate change, geographic features, and habitat heterogeneity on spatial patterns of genetic diversity. In this study we combine thousands of genotyping-by-sequencing (GBS) loci with mtDNA sequences (ND1) from the Texas Horned Lizard (Phrynosoma cornutum) to quantify relative support for different catalysts of diversification. Phylogenetic and clustering analyses of the GBS data indicate support for at least three primary populations. The spatial distribution of populations appears concordant …

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Global Population Divergence Of A Cosmopolian Desert Plant, Victor Ryan Alfaro Sep 2021

Global Population Divergence Of A Cosmopolian Desert Plant, Victor Ryan Alfaro

Biology ETDs

Genetic and phenotypic variation can have different patterns within a species if it has populations with contrasting histories. Populations can have discrete differences that are shaped by different evolutionary scenarios, but within each population, range, or region, traits and association with fitness can also be affected by both edaphic and landscape variation. For my dissertation, I surveyed and experimentally analyzed variation and adaptive potential in Sahara mustard (Brassica tournefortii), a desert annual that has endemic, invasive, and agricultural populations in Africa, Asia, and the Americas. Although my multi-trait analysis generated complex results, my findings can be applied to …

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A Reevaluation Of The Phylogeography Of The Chattahoochee Slimy Salamander (Plethodon Chattahoochee) Using Next-Generation Genomic Data, Jadin Cross Aug 2021

A Reevaluation Of The Phylogeography Of The Chattahoochee Slimy Salamander (Plethodon Chattahoochee) Using Next-Generation Genomic Data, Jadin Cross

Symposium of Student Scholars

The Plethodon glutinosus species complex is a group of large-bodied, lungless salamanders that are widespread across the eastern United States. Species in this group are morphologically cryptic and were originally delimited using allozyme data, but in most cases, the extent of contemporary gene flow between named taxa has not be rigorously evaluated. The Appalachian Mountains of northern Georgia are home to several members of this group—including P. glutinosus, P. teyahalee, P. chlorobryonis, and P. chattahoochee. P. chattahoochee has been found to be especially cryptic both morphologically and genetically as both intraspecific genetic variation and species boundaries within …

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Leveraging Multiple Data Sources: How Catch Data, Metadata, And Genetic Samples Can Aid The Recovery Of Endangered Smalltooth Sawfish (Pristis Pectinata), Kelcee Smith Jul 2021

Leveraging Multiple Data Sources: How Catch Data, Metadata, And Genetic Samples Can Aid The Recovery Of Endangered Smalltooth Sawfish (Pristis Pectinata), Kelcee Smith

LSU Doctoral Dissertations

The small population sizes characteristic of many imperiled species means that they are vulnerable to both demographic and genetic extinction threats. Responses to these threats (e.g., population trends, genetic diversity estimates) are often difficult to obtain, but critical for conservation. Thus, researchers studying imperiled species may have to consult multiple data sources, collaborate with a wide variety of stakeholders, or ask new questions about previously collected data. I used this approach to understand more about the United States (U.S.) population of Pristis pectinata, an endangered elasmobranch that has declined up to 95% due to habitat loss and bycatch in …

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The Effects Of Climate And Demographic History In Shaping Genomic Variation Across Populations Of The Desert Horned Lizard (Phrynosoma Platyrhinos), Keaka Farleigh, Sarah A. Vladimirova, Christopher Blair, Jason T. Bracken, Nazila Koochekian, Drew R. Schield, Daren C. Card, Nicholas Finger, Jonathan Henault, Adam D. Leaché, Todd A. Castoe, Tereza Jezkova Jul 2021

The Effects Of Climate And Demographic History In Shaping Genomic Variation Across Populations Of The Desert Horned Lizard (Phrynosoma Platyrhinos), Keaka Farleigh, Sarah A. Vladimirova, Christopher Blair, Jason T. Bracken, Nazila Koochekian, Drew R. Schield, Daren C. Card, Nicholas Finger, Jonathan Henault, Adam D. Leaché, Todd A. Castoe, Tereza Jezkova

Publications and Research

Species often experience spatial environmental heterogeneity across their range, and populations may exhibit signatures of adaptation to local environmental characteristics. Other population genetic processes, such as migration and genetic drift, can impede the effects of local adaptation. Genetic drift in particular can have a pronounced effect on population genetic structure during large-scale geographic expansions, where a series of founder effects leads to decreases in genetic variation in the direction of the expansion. Here, we explore the genetic diversity of a desert lizard that occupies a wide range of environmental conditions and that has experienced post-glacial expansion northwards along two colonization …

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Genomic And Ecological Dimensions Of Malagasy Reptile And Amphibian Biodiversity, Arianna L. Kuhn Jun 2021

Genomic And Ecological Dimensions Of Malagasy Reptile And Amphibian Biodiversity, Arianna L. Kuhn

Dissertations, Theses, and Capstone Projects

A long history of isolation coupled with complex topographic and ecological landscapes makes Madagascar ideal for exploring the historical factors that have shaped patterns of population diversity and endemism. Many species-level studies have suggested Late Quaternary climate change may have influenced population dynamics in the tropics, but Madagascar’s ecologically unique biomes or individual species properties may have driven idiosyncratic responses to these shifts. Using community-scale population genetic data I implement a hierarchical approximate Bayesian computation (hABC) approach to evaluate the degree of synchronous population expansion during glacial cycles across herpetofaunal assemblages both within and across discrete biomes and taxonomic groups. …

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Dynamic Observers For Unknown Populations, Chris Guiver, Nathan Poppelreiter, Richard Rebarber, Brigitte Tenhumberg, Stuart Townley Jun 2021

Dynamic Observers For Unknown Populations, Chris Guiver, Nathan Poppelreiter, Richard Rebarber, Brigitte Tenhumberg, Stuart Townley

Brigitte Tenhumberg Papers

Dynamic observers are considered in the context of structuredpopulation modeling and management. Roughly, observers combine a known measured variable of some process with a model of that process to asymptotically reconstruct the unknown state variable of the model. We investigate the potential use of observers for reconstructing population distributions described by density-independent (linear) models and a class of density-dependent (nonlinear) models. In both the density-dependent and -independent cases, we show, in several ecologically reasonable circumstances, that there is a natural, optimal construction of these observers. Further, we describe the robustness these observers exhibit with respect to disturbances and uncertainty in …

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Dynamics Of Hybrid Zones At A Continental Scale, Bradley T. Martin May 2021

Dynamics Of Hybrid Zones At A Continental Scale, Bradley T. Martin

Graduate Theses and Dissertations

Hybridization has traditionally been viewed as a happenstance that negatively impacts populations, but is now recognized as an important evolutionary mechanism that can substantially impact the evolutionary trajectories of gene pools, influence adaptive capacity, and contravene or reinforce divergence. Physiographic processes are important drivers of dispersal, alternately funneling populations into isolation, promoting divergence, or facilitating secondary contact of diverged populations, increasing the potential for hybridization. In North America, glacial-interglacial cycles and geomorphological changes have provided a dynamic backdrop over the last two million years that promoted such oscillations of population contraction and expansion. These biogeographic processes have resulted in regional …

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208— Describing Genetic Diversity In A Non-Native Ant-Mimicking Spider, Cassidy Mills, Jennifer L. Apple Apr 2021

208— Describing Genetic Diversity In A Non-Native Ant-Mimicking Spider, Cassidy Mills, Jennifer L. Apple

GREAT Day Posters

The ant-mimicking spider Myrmarachne formicaria (Salticidae) is a species native to Eurasia and was first identified in North America in 2001. It has since been found in many locations in the Northeast including western New York, western Pennsylvania, northeastern Ohio, and southern Ontario. Little is known about its introduction to North America and how it has dispersed since. By characterizing the mitochondrial genetic diversity of this species, we can learn about its introduction history and dispersal patterns in North America. Sequencing of a 600-bp mitochondrial DNA gene region spanning the 16s rRNA, leucine tRNA, and part of the ND1 gene …

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A Whole-Genome Scan For Association With Invasion Success In The Fruit Fly Drosophila Suzukii Using Contrasts Of Allele Frequencies Corrected For Population Structure, Laure Olazcuaga, Anne Loiseau, Hugues Parrinello, Mathilde Paris, Antoine Fraimout, Christelle Guedot, Lauren M. Diepenbrock, Marc Kenis, Jinping Zhang, Xiao Chen, Nicolas Borowiec, Benoit Facon, Heidrun Vogt, Donald K. Price, Heiko Vogel, Benjamin Prud'homme, Arnaud Estoup, Mathieu Gautier Apr 2021

A Whole-Genome Scan For Association With Invasion Success In The Fruit Fly Drosophila Suzukii Using Contrasts Of Allele Frequencies Corrected For Population Structure, Laure Olazcuaga, Anne Loiseau, Hugues Parrinello, Mathilde Paris, Antoine Fraimout, Christelle Guedot, Lauren M. Diepenbrock, Marc Kenis, Jinping Zhang, Xiao Chen, Nicolas Borowiec, Benoit Facon, Heidrun Vogt, Donald K. Price, Heiko Vogel, Benjamin Prud'homme, Arnaud Estoup, Mathieu Gautier

Life Sciences Faculty Research

Evidence is accumulating that evolutionary changes are not only common during biological invasions but may also contribute directly to invasion success. The genomic basis of such changes is still largely unexplored. Yet, understanding the genomic response to invasion may help to predict the conditions under which invasiveness can be enhanced or suppressed. Here, we characterized the genome response of the spotted wing drosophila Drosophila suzukii during the worldwide invasion of this pest insect species, by conducting a genome-wide association study to identify genes involved in adaptive processes during invasion. Genomic data from 22 population samples were analyzed to detect genetic …

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Henry V. Howe And His Collection Of Foraminifera At Louisiana State University, Lorene E. Smith, Barun K. Sen Gupta Mar 2021

Henry V. Howe And His Collection Of Foraminifera At Louisiana State University, Lorene E. Smith, Barun K. Sen Gupta

Occasional Papers of the Museum of Natural Science, Louisiana State University

Henry V. Howe, the founder of the current academic program in geology at Louisiana State University (LSU), and a renowned ostracod specialist, was also a distinguished foraminiferal paleontologist. His best work in that field, involving the discovery of many new species, was on the taxonomy of Eocene Foraminifera of Louisiana. The present H.V. Howe Type Collection of Microfossils began with Howe’s gift of slides to LSU. This collection, enriched by contributions from later workers, now includes over 580 slides of foraminiferal primary type specimens, with holotypes and syntypes of 361 species and 15 taxa labeled as “varieties.” Information regarding these …

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A New Vine Snake (Reptilia, Colubridae, Oxybelis) From Peru And Redescription Of O. Acuminatus, Robert C. Jadin, Michael J. Jowers, Sarah A. Orlofske, William E. Duellman, Christopher Blair, John C. Murphy Jan 2021

A New Vine Snake (Reptilia, Colubridae, Oxybelis) From Peru And Redescription Of O. Acuminatus, Robert C. Jadin, Michael J. Jowers, Sarah A. Orlofske, William E. Duellman, Christopher Blair, John C. Murphy

Publications and Research

The Brown Vine Snake, Oxybelis aeneus, was until recently considered a single species, distributed from southern Arizona through the Neotropics into southeastern Brazil. However, newly conducted research restructured the species with a substantial taxonomic revision, recognizing five additional taxa (i.e. O. koehleri, O. microphthalmus, O. potosiensis, O. rutherfordi, O. vittatus) in this species complex. This revision focused on populations in North America, Central America, and northern South America while neglecting the southern portion of its distribution. Here, we examine the taxonomic history of the complex and use it along with specimen data to resurrect O. acuminatus from southeastern Brazil. Finally, …

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Age, Growth, And Mortality Of Atlantic Tripletail In The North-Central Gulf Of Mexico, Amanda E. Jefferson, Matthew B. Jargowsky, Meagan N. Schrandt, Pearce T. Cooper, Sean P. Powers, John Dindo, J. Marcus Drymon Jan 2021

Age, Growth, And Mortality Of Atlantic Tripletail In The North-Central Gulf Of Mexico, Amanda E. Jefferson, Matthew B. Jargowsky, Meagan N. Schrandt, Pearce T. Cooper, Sean P. Powers, John Dindo, J. Marcus Drymon

University Faculty and Staff Publications

In the southeastern USA and the Gulf of Mexico (GOM), Atlantic Tripletail Lobotes surinamensis are increasingly targeted by recreational anglers, indicating that stock status should be assessed. A critical need for such assessments is age-specific data; however, previous studies have drawn conflicting conclusions regarding the most appropriate structure for aging. Moreover, growth parameters and mortality rates for GOM Atlantic Tripletail are unknown. Therefore, the goals of this study were to (1) evaluate sagittal otoliths and first dorsal spines as aging structures; (2) model combined and sex-specific growth; and (3) estimate mortality rates for GOM Atlantic Tripletail. From 2012 to 2019, …

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Genetic Diversity & Connectivity Of Chasmanthium Latifolium (Poaceae) In Pennsylvania & The Effect On Conservation Status Of A Rare Species, Jonathan D. Hayes Jan 2021

Genetic Diversity & Connectivity Of Chasmanthium Latifolium (Poaceae) In Pennsylvania & The Effect On Conservation Status Of A Rare Species, Jonathan D. Hayes

Honors Theses

Chasmanthium latifolium (Michx.) Yates (Poaceae) is a loosely colonial, rhizomatous, perennial grass species that lives in riparian habitats, making it fittingly referred to as river oats. Native to the southern Midwest and the eastern half of the United States, C. latifolium reaches the northeastern edge of its range in Pennsylvania. Within Pennsylvania, eleven extant C. latifolium populations are found along four waterways: the Monongahela River, the Susquehanna River, and two tributaries to the Susquehanna River. This limited state distribution exhibits an east-west disjunct distribution, where western populations are largely separated from eastern populations with one centrally located population. Between the …

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Comparative Conservation Genomics Of A Suite Of Imperiled Freshwater Mussels, Scott C. Meyer Jan 2021

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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Lepidopteran Granivory Reduces Seed Counts In A Rare Species Of Riparian Scour Prairies, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine Jan 2021

Lepidopteran Granivory Reduces Seed Counts In A Rare Species Of Riparian Scour Prairies, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine

Faculty Journal Articles

In Pennsylvania Baptisia australis var. australis is found along only four waterways: the Allegheny River, Youghiogheny River, Clarion River, and Red Bank Creek. Because of its limited distribution and small number of extant populations, the species is considered state-threatened in Pennsylvania. In addition, the riparian prairie habitat that Pennsylvania Baptisia australis var. australis is restricted to is also in decline and considered vulnerable. Because of these conservation concerns, insights into the natural history of the taxon in the state is valuable and will inform conservation efforts. Field surveys and fruit collections along the Allegheny River and herbarium collections were used …

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Investigation Into The Genetic Provenance Of Three Rare Plants With East-West Disjunction Patterns In Pennsylvania., Scott Schuette, Christopher T. Martine Jan 2021

Investigation Into The Genetic Provenance Of Three Rare Plants With East-West Disjunction Patterns In Pennsylvania., Scott Schuette, Christopher T. Martine

Other Faculty Research and Publications

Rare plant conservation relies on an understanding of the natural history, biology and ecology, and real and potential threats to their populations to inform state regulations that serve to protect the species from extirpation. This work often involves extensive field surveys over several years to determine population sizes and whether those populations are seeing reductions in number of individuals necessary to maintain the genetic diversity within and between those populations. Species and populations with high genetic diversity are better equipped to withstand sudden changes to their habitats that derive from land use changes and changing climate. There are a variety …

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