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Articles 31 - 60 of 333

Full-Text Articles in Other Ecology and Evolutionary Biology

Assessing Genetic Diversity And Population Structure In The Imperiled Aconitum Reclinatum (White Monkshood), An Endemic Wildflower Of Central Appalachia, Diamanda A. Zizis Jan 2025

Assessing Genetic Diversity And Population Structure In The Imperiled Aconitum Reclinatum (White Monkshood), An Endemic Wildflower Of Central Appalachia, Diamanda A. Zizis

Master’s Theses

Aconitum reclinatum, white monkshood (Ranunculaceae), is a Pennsylvania critically imperiled plant species found in five states of the Appalachian region of the United States: Pennsylvania, West Virginia, Virginia, North Carolina, and Tennessee. This plant is adapted to cool, moist environments but faces threats from increasing habitat loss, deer browse, logging, and changes in rainfall and temperature associated with climate change. Comprehensive knowledge of A. reclinatum genetic population structure remains limited. To address this, we collaborated with Natural Heritage programs within the range of A. reclinatum to sample populations across the species distribution and generate a genotyping-by-sequencing data set of …

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The Prize Biter Of Modernity? Investigating Killer Whale Bite Mechanics, Daniel Hong Jan 2025

The Prize Biter Of Modernity? Investigating Killer Whale Bite Mechanics, Daniel Hong

West Chester University Graduate Theses, Dissertations, and Final Projects

Although the killer whale (Orcinus orca) is a cosmopolitan apex predator, very little work has been done on its feeding biomechanics. Here I use finite element analysis to investigate the mandibular stiffness of a juvenile male Bigg’s killer whale, and compare it to that of the false killer whale (Pseudorca crassidens) and the saltwater crocodile (Crocodylus porosus). Full mandibles and left and right halves of mandibles are simulated under FEA. I also estimate the total jaw muscle force produced by the Bigg’s killer whale using the dry skull method. The killer whale lacks an …

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Study Of The Brain Anatomy Of Three Extinct Marsupials: Thylacinus Cynocephalus, Thylacoleo Carnifex, And Silvabestius Johnnilandi, Francisco Garcia Dec 2024

Study Of The Brain Anatomy Of Three Extinct Marsupials: Thylacinus Cynocephalus, Thylacoleo Carnifex, And Silvabestius Johnnilandi, Francisco Garcia

Honors Program Theses and Research Projects

Marsupials are pouched mammals that today are mainly found in Australasia and South America. Marsupials have proven to be quite intriguing to evolutionary biologists who note how some marsupials resemble placentals in anatomy due to convergent evolution, with both marsupials and placentals filling similar niches in their respective environments. As of today, studies interested in marsupial brain evolution have published descriptions of cranial endocasts for several species of marsupials, with the number of descriptions seeing a massive boost over the last 20 years with the arrival of CT imaging technology. However, no comprehensive study of brain evolution in marsupials has …

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Bioindicators Of Mercury In Riverine Systems, Kathryn Mudica Dec 2024

Bioindicators Of Mercury In Riverine Systems, Kathryn Mudica

All-Inclusive List of Electronic Theses and Dissertations

This study focuses on the bioaccumulation and biomagnification of mercury in freshwater food webs, with emphasis on bioindicators, such as macroinvertebrates, crayfish, and river otters. Despite regulatory efforts and advancements in monitoring, significant gaps remain in understanding mercury dynamics in freshwater systems—especially regarding its transport, methylation, and bioavailability across different ecosystems. To address these knowledge gaps, this study adopts a biocentric approach, emphasizing the role of living organisms in their environment. By utilizing macroinvertebrates, crayfish, and river otters as bioindicators, we aim to assess mercury bioavailability and distribution. These organisms provide varying temporal and spatial scales of mercury accumulation, offering …

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Analyzing Head Morphology Trends With Increasing Population Density In A Jamaican Lizard Species, Lillian Durand Dec 2024

Analyzing Head Morphology Trends With Increasing Population Density In A Jamaican Lizard Species, Lillian Durand

2024 Fall Honors Capstone Projects - Archive

Anolis lizards are model organisms for studying natural selection and evolutionary processes. One trait that is hypothesized to be advantageous for males is head size, as larger heads lead to stronger bite forces and increased likelihood in outcompeting other males for mates. To better understand how linked head size and intraspecific competition are, the head morphology of male A. lineatopus was analyzed among Jamaican populations with varying levels of population density. Population densities were determined using standardized plot surveys and mark resight models. Head dimensions and body condition for individual lizards were measured at each site. My study found that …

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Evaluating The Roles Of Pollinators In Shaping The Floral Color Variation Of Phacelia Dubia, Katherine Riddle Dec 2024

Evaluating The Roles Of Pollinators In Shaping The Floral Color Variation Of Phacelia Dubia, Katherine Riddle

All Theses

Floral color variation within a species is a common occurrence and its maintenance has been a long-standing question in evolutionary biology. Differences in flower color between populations can be shaped by pollinator-mediated selection. Pollinators can exhibit innate and learned preferences for color that may influence floral color variation. These preferences may be molded by the visual environment in which pollinators forage. Most current understanding of how pollinators shape floral color variation involves dramatic differences in dominant pollinators between populations (e.g., hawkmoth vs. bee) and most behavioral work utilized model pollinators like honeybee and bumble bee. However, less is known about …

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Human Impacts On Mammal Diversity From The Pleistocene To The Present, Carson P. Hedberg Nov 2024

Human Impacts On Mammal Diversity From The Pleistocene To The Present, Carson P. Hedberg

Biology ETDs

Humans have fundamentally altered the planet’s biodiversity. It is critical to characterize these changes, but also to understand how they impact the structure and function of modern ecosystems. This dissertation investigates how anthropogenically mediated species losses and/or introductions influence ecological function and community structure in mammals across multiple temporal and spatial scales. We found that selective loss of large-bodied mammals over the Late Quaternary has led to severe losses in functional diversity in modern ecosystems, suggesting megafaunal mammals contribute distinct ecological functions. These changes to mammal diversity and distribution over millennia have altered both global patterns in functional diversity and …

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The Influence Of Environmental Change On Genetic Diversity Across Spatial And Taxonomic Scales, Connor M. French Sep 2024

The Influence Of Environmental Change On Genetic Diversity Across Spatial And Taxonomic Scales, Connor M. French

Dissertations, Theses, and Capstone Projects

The spatial distribution of genetic diversity is of interest to biodiversity scientists and conservationists and is a fundamental metric of biodiversity. Genetic diversity patterns across spatial and taxonomic scales contain information about population and assemblage dynamics that can convey their resilience to environmental change. Ectotherms are especially linked to their environments and may be especially sensitive to fluctuations in the environment over time. Herein, I investigate global and regional patterns of genetic diversity in two groups of ectotherms, insects and lizards, to understand the relationship between environmental change and genetic diversity, from populations to assemblages. Overall, my research aims to …

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The Role Of Elevation In The Migration, Physiology, And Genomic Diversification Of Birds, Jessie L. Williamson Aug 2024

The Role Of Elevation In The Migration, Physiology, And Genomic Diversification Of Birds, Jessie L. Williamson

Biology ETDs

Elevational gradients cause profound eco-climatic variation across short distances. Partial pressure of oxygen (PO2) is a severe challenge that organisms face at high elevations; due partly to specialization on PO2, most Neotropical bird species have narrow elevational ranges. However, a small fraction are elevational generalists that span sea level to high elevations, and a subset undertake extreme migratory journeys from low to high elevations biannually. My dissertation combines diverse approaches across levels of biological organization to understand how elevation impacts the ecology, evolution, physiology, and migration of montane birds. I examined ‘extreme’ elevational …

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Spectral Sensitivity Of Circadian Entrainment In Araneoid And Non-Araneoid Spiders, Craig Campbell Aug 2024

Spectral Sensitivity Of Circadian Entrainment In Araneoid And Non-Araneoid Spiders, Craig Campbell

Electronic Theses and Dissertations

Artificial lighting at night is a growing worldwide phenomenon that can negatively impact flora and fauna in the surrounding area. With new technology, there is now opportunity for change: newer LEDs can emit specific wavelengths of light that may be less ecologically damaging. In this study, we aim to describe the circadian spectral sensitivity of two phylogenetically distant urban spider species with similar life histories, the Araneoid Parasteatoda tepidariorum and non-Araneoid Pholcus manueli, to determine differences between them. We exposed these spiders to progressively dimmer levels of white, blue, green, or red light. Despite evidence that spiders lack visual …

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Records Of The Red-Bellied Snake (Storeria Occipitomaculata) In Central And Northeastern Nebraska, Taylor Lowe, Sarah M. Bailey, Dan D. Fogell, Keith Geluso Jul 2024

Records Of The Red-Bellied Snake (Storeria Occipitomaculata) In Central And Northeastern Nebraska, Taylor Lowe, Sarah M. Bailey, Dan D. Fogell, Keith Geluso

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Red-bellied Snakes (Storeria occipitomaculata) are a distinctive, small species that live in moist woodlands throughout much of eastern North America. In the Great Plains, isolated populations exist in South Dakota, Wyoming, and Nebraska. In Nebraska, the only known extant population occurs in wooded riparian habitats along the Big Bend Reach of the Platte River in southcentral parts of the state. Herein, we report on new county records of Red-bellied Snakes in Nebraska, with two observations from Merrick County along the Platte River adjacent to known populations and two observations of a new population in the extreme northeastern part …

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Seed Dispersal By Martu Peoples Promotes The Distribution Of Native Plants In Arid Australia, Rebecca Bliege Bird, Douglas Bird, Christopher T. Martine, Chloe Mcguire, Leanne Greenwood, Desmond Taylor, Tanisha M. Williams, Peter M. Veth Jul 2024

Seed Dispersal By Martu Peoples Promotes The Distribution Of Native Plants In Arid Australia, Rebecca Bliege Bird, Douglas Bird, Christopher T. Martine, Chloe Mcguire, Leanne Greenwood, Desmond Taylor, Tanisha M. Williams, Peter M. Veth

Faculty Journal Articles

Commensal relationships between wild plants and their dispersers play a key ecological and evolutionary role in community structure and function. While non-human dispersers are often considered critical to plant recruitment, human dispersers have received much less attention, especially when it comes to non-domesticated plants. Australia, as a continent historically characterized by economies reliant on non-domesticated plants, is thus a key system for exploring the ecological role of people as seed dispersers in the absence of agriculture. Here, we utilize a controlled observation research design, employing ecological surveys and ethnographic observations to examine how seed dispersal and landscape burning by Martu …

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Scientific Note: An Incursion Of The Widely-Cultivated Katsura (Cercidiphyllum Japonicum, Cercidiphyllaceae) In Pennsylvania, Kayleigh R. Long, Melody P. Sain, Elizabeth H. Williams, Christopher T. Martine Jul 2024

Scientific Note: An Incursion Of The Widely-Cultivated Katsura (Cercidiphyllum Japonicum, Cercidiphyllaceae) In Pennsylvania, Kayleigh R. Long, Melody P. Sain, Elizabeth H. Williams, Christopher T. Martine

Faculty Journal Articles

Cercidiphyllum japonicum (katsura) is a dioecious tree native to China and Japan. Although imperiled in parts of its natural distribution, the species has become quite common as a cultivated tree in temperate North America. The species is noted as occasionally escaping cultivation in the eastern United States, but few records of established incursions (and the conditions under which they might recruit) exist in the literature. We here report an incursion of C. japonicum in central Pennsylvania, along with notes on seedling recruitment on the Bucknell University campus.

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Climate And Shared Evolutionary History Drive Trait Variation Among Species Of Neotropical Understory Monocots, Eleinis Ávila-Lovera, Oscar M. Vargas, Jennifer L. Funk, Kathleen M. Kay, Gregory R. Goldsmith Jun 2024

Climate And Shared Evolutionary History Drive Trait Variation Among Species Of Neotropical Understory Monocots, Eleinis Ávila-Lovera, Oscar M. Vargas, Jennifer L. Funk, Kathleen M. Kay, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Environmental variation commonly drives functional trait diversity within species, among species, and across communities. Climate and shared evolutionary history can both influence trait–environment relationships. We studied variation in plant functional traits among closely related Costus species occurring across environmental gradients, the extent to which this variation occurs within single species, and how that variation may be influenced by shared evolutionary history. We measured leaf, aboveground stem, rhizome, and fine root traits of 17 species of Costus in eight sites in Costa Rica and Panama, which varied in elevation, temperature, and precipitation. We then assessed the relationships among traits and environmental …

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Optimization Of Coral Restoration Along The Florida Reef Tract, Raymond Barry Banister May 2024

Optimization Of Coral Restoration Along The Florida Reef Tract, Raymond Barry Banister

Theses and Dissertations

Historically, the reefs of Florida were dominated by two framework-building corals, Acropora cervicornis and A. palmata. However, these two populations have declined by 95% since the 1970s. The predominant contributors to the coral decline have been ocean warming and disease. In response to the decline, restoration organizations were established to improve survival, growth, and reproduction. Yet, there are gaps in current restoration practices and our knowledge of effective restoration techniques. This study uses large datasets to develop models that predict the most optimal locations for coral restoration in Florida and examines the relationships between the occurrence of wild acroporids …

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Quantifying How Natural History Traits Contribute To Bias In Community Science Engagement: A Case Study Using Orbweaver Spiders, John Deitsch, Angela Chuang, David R. Nelsen, Michael Sitvarin, David Coyle Apr 2024

Quantifying How Natural History Traits Contribute To Bias In Community Science Engagement: A Case Study Using Orbweaver Spiders, John Deitsch, Angela Chuang, David R. Nelsen, Michael Sitvarin, David Coyle

Achieve

Online citizen science platforms can be crucial to the scientific and regulatory community, but inherent biases based on organism traits can influence the likelihood of a species being reported and accurately identified. We explored how traits of orb weaving spiders impact data in iNaturalist, using the invasive Jorō spider as a case study. This species is an outlier among orbweavers due to its large size and bright coloration, and was the most frequently reported species, with the most identifications and research-grade observations. It was also reported by less experienced users on average, highlighting its potential role as a gateway species …

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The Descent Of Anolis: Assemblages, Convergence, And Ecomorphological Evolution, Christopher G. Anderson Apr 2024

The Descent Of Anolis: Assemblages, Convergence, And Ecomorphological Evolution, Christopher G. Anderson

Biology ETDs

The evolutionary outcomes we observe in modern organisms, particularly associations between phenotypes and environments, have been and remain an invaluable tool in interpreting the biological phenomena that shape our world. In the following chapters, I leverage a comprehensive phylogenetic and morphological dataset for 351 species comprising a diverse group of arboreal lizards, the Anolis clade, to explore how communities and morphologies evolve. First, I characterized patterns among coexisting lineages of Anolis to reveal a general pattern of phylogenetic relatedness among lineages comprising assemblages and identify differences attributable to a biogeographic variable. Then I examined the morphological consequences associated with the …

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Climate Change-Associated Declines In Water Clarity Impair Feeding By Common Loons, Walter H. Piper, Max R. Glines, Kevin C. Rose Mar 2024

Climate Change-Associated Declines In Water Clarity Impair Feeding By Common Loons, Walter H. Piper, Max R. Glines, Kevin C. Rose

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Climate change has myriad impacts on ecosystems, but the mechanisms by which it affects individual species can be difficult to pinpoint. One strategy to discover such mechanisms is to identify a specific ecological factor related to survival or reproduction and determine how that factor is affected by climate. Here we used Landsat imagery to calculate water clarity for 127 lakes in northern Wisconsin from 1995 to 2021 and thus investigate the effect of clarity on the body condition of an aquatic visual predator, the common loon (Gavia immer). In addition, we examined rainfall and temperature as potential predictors …

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Reproductive Biology Of The Jellyfish Outbreak Along The Uae Coastal Waters, Amrutha Aravind Mar 2024

Reproductive Biology Of The Jellyfish Outbreak Along The Uae Coastal Waters, Amrutha Aravind

Dissertations

Jellyfish are a ubiquitous occurrence in the world’s oceans. During the past decades, dramatic spatial increases and temporal shifts in jellyfish distributions have been reported around the world. The United Arab Emirates (UAE) coastal area also has experienced several blooms along with severe adverse impacts on its economic facilities. Few studies have been conducted within the Arabian Gulf and the Sea of Oman, to identify the blooming species and the environmental parameters that favor such breakouts. The present study aimed to identify the jellyfish species found along the coastal area of UAE and trying to link their occurrence with seasonal …

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Environmental Biology Masters Capstone, Antonio Gonzalez-Pita Jan 2024

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …

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Estimation Of Probability Of Habitat Use Of Roosevelt Elk On The Olympic Peninsula, Vincent Michael Gugliotti Jan 2024

Estimation Of Probability Of Habitat Use Of Roosevelt Elk On The Olympic Peninsula, Vincent Michael Gugliotti

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Estimating the probability of habitat use for a particular species is crucial to the direct management and conservation of that species. Without knowledge of habitat preferences, managers cannot effectively focus efforts on vital resources or landscape types. However, modelling probability of habitat use can be done in several ways which leaves room for variation and uncertainty in the estimates produced by each method. This study is an examination of the variation between two estimates of probability of habitat use while focusing on a particular subspecies of elk that inhabits a unique ecosystem relative to other elk subspecies. I modeled elk …

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Occupancy Of The Little Grass Frog (Pseudacris Ocularis), An Overlooked Longleaf Endemic, In A Managed Landscape, Anna M. Humphrey Jan 2024

Occupancy Of The Little Grass Frog (Pseudacris Ocularis), An Overlooked Longleaf Endemic, In A Managed Landscape, Anna M. Humphrey

Theses, Dissertations and Capstones

Amphibians are declining globally, with many declines associated with habitat loss. The longleaf pine (Pinus palustris) ecosystem historically covered most of the southeastern United States and supports a host of endemic amphibians. This ecosystem has declined by over 97% in the last two hundred years and many associated species have declined with it. The Little Grass Frog (Pseudacris ocularis) is a longleaf pine endemic anuran that has been understudied and under-surveyed; almost no information is known on the ecology of this species and no population studies have been conducted. My goals were to create an acoustic …

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Bird Predation On Coho Salmon (Oncorhynchus Kisutch) In Humboldt Bay, Colton J. Dixon Jan 2024

Bird Predation On Coho Salmon (Oncorhynchus Kisutch) In Humboldt Bay, Colton J. Dixon

Cal Poly Humboldt theses and projects

Coho Salmon (Oncorhynchus kisutch) populations along the west coast of the United States are declining. In Humboldt County, located in northwestern California, Coho Salmon have been in decline since their federal listing as threatened in 1997, primarily due to habitat loss from logging, agriculture, and urban development. Although these anthropogenic factors caused salmon populations to decline, bird predation may also be hindering population recovery, as evidenced by the recovery of Passive Integrated Transponder (PIT) tags, originally implanted in Coho Salmon, from bird colonies in Humboldt Bay. This study examines predation by Double-crested Cormorants (Phalacrocorax auritus), Caspian …

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Interdisciplinary Learning: How Different Ways Of Thinking Can Fuel Passion And Expand Understanding., Allison Amy Peschek Jan 2024

Interdisciplinary Learning: How Different Ways Of Thinking Can Fuel Passion And Expand Understanding., Allison Amy Peschek

Undergraduate Theses, Professional Papers, and Capstone Artifacts

This Capstone project was created to show the profound experience resulting from an extended range of interdisciplinary learning, and how different methods, when paired together, can enhance a learning experience. This was a personal project of exploration into those different angles, and primarily focused on avenues of logical and creating learning, respectively. These methods have been implemented by this author often in the past, but this capstone will explore this concept further, as there is a lot of potential in combining these different methods and biases in learning, to both further passion and understanding as a learner, but to also …

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Endophytic Fungi Associated With Galls And Host Plants Of Asphondylia Borrichiae (Diptera: Cecidomyiidae), Shannon Lynn Sharpe Jan 2024

Endophytic Fungi Associated With Galls And Host Plants Of Asphondylia Borrichiae (Diptera: Cecidomyiidae), Shannon Lynn Sharpe

UNF Graduate Theses and Dissertations

Asphondylia borrichiae, like other gall-forming gnats, are obligate symbionts to the endophytic fungi (EF) they deposit when laying eggs. Asphondylia spp. and EF are important biocontrol agents, yet details surrounding their diversity, life cycles, and host interactions remain poorly understood. Galls and leaf-stem tissues from two host plants were surveyed to identify and compare EF diversity between the host tissues and species of A. borrichiae. Identification of 114 isolates was carried out by sequencing the internal transcribed spacer (ITS 1/4 primers). Pairwise alignments in multiple genetic databases were bolstered by phylogenetic analyses using maximum parsimony and maximum likelihood …

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Evaluating The Use Of Baited Remote Underwater Video (Bruv) In Assessing Shark And Fish Populations In A Low Visibility Estuarine System, The Tolomato River, Fl, Usa, Sarah Worthington Jan 2024

Evaluating The Use Of Baited Remote Underwater Video (Bruv) In Assessing Shark And Fish Populations In A Low Visibility Estuarine System, The Tolomato River, Fl, Usa, Sarah Worthington

UNF Graduate Theses and Dissertations

Recently, there has been increasing use of baited remote underwater video (BRUV) surveys for assessing shark and fish populations in marine ecosystems. This approach can be useful because it may provide a non-destructive, non-extractive, and cost-effective alternative to traditional fishing-based methods. However, to date, most studies using BRUVs have focused on their use in high-visibility ecosystems, such as tropical reefs. Furthermore, few studies have compared results from BRUV surveys with those obtained using traditional methods to evaluate the efficacy of this approach. Therefore, the goal of this study was to evaluate the effectiveness of using BRUV surveys to assess shark …

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Quantifying The Influences Of Abiotic And Biotic Factors On Post-Fire Vegetation In The Southwestern Us, Joseph Lafayette Crockett Dec 2023

Quantifying The Influences Of Abiotic And Biotic Factors On Post-Fire Vegetation In The Southwestern Us, Joseph Lafayette Crockett

Biology ETDs

The ongoing warming associated with climate change is increasing the flammability of southwestern US dry forests. As larger fractions of the landscape are impacted by high-severity fire, the potential exists for forests to convert to non-forest. Given that the forested area in the southwestern US is an important contributor of ecosystem services, quantifying limitations to vegetation establishment is critical to informing post-fire recovery efforts and understanding how ongoing climate change will limit seedling establishment in the future. To that end, this dissertation focuses on post-fire vegetation recovery of southwestern forests. First, I report on the influence of precipitation and topography …

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Effects Of A Major Hurricane On Dynamics, Structure, And Composition Of Mississippi River Delta Forests, Lance C. Umlang Oct 2023

Effects Of A Major Hurricane On Dynamics, Structure, And Composition Of Mississippi River Delta Forests, Lance C. Umlang

LSU Doctoral Dissertations

Tropical cyclones recurrently influence coastal forests worldwide. Tree survival (resistance) and post-cyclone recruitment (resilience) can vary with cyclone intensity, producing differences in composition, arboreal structure, and dynamics among affected forests. Studies of tropical cyclone wind effects on coastal forests typically emphasize damage more than post-cyclone responses. We hypothesized that intense cyclones might produce large, stratum-dependent effects that prevent affected forests from returning to pre-storm conditions. We explored direct effects of major Hurricane Katrina and post-hurricane changes in oak-dominated bottomland and cypress/tupelo-dominated swamp forests within the inactive portion of the Mississippi River deltaic plain. Overall mortality was high (14-25%) but concentrated …

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Compensating For Effects Of Autotomy On Locomotion In Stink Bugs (Halyomorpha Halys), Lilian C. Jubb Oct 2023

Compensating For Effects Of Autotomy On Locomotion In Stink Bugs (Halyomorpha Halys), Lilian C. Jubb

Longwood Senior Thesis Proposal

Autotomy is the voluntary release of an appendage, typically to avoid predation or entrapment. Autonomy of a single leg can have minimal effects on locomotion in arthropods with more than six legs. Hexapods, however, use a double-tripod gait which is completely disrupted with the loss of a single leg, thus locomotor performance should be greatly reduced leading to lower survival. Autotomy is so costly to locomotion that some insects regenerate a lost limb in a subsequent molt leading to reduced investment in other important functions (e.g. reproduction). Autotomy persists in adult hexapods with no opportunity for regeneration, which suggests some …

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Resolving The Paradox Of Polyploidy: Underexplored Facets Of Polyploid Plants, Benjamin P. Gerstner Aug 2023

Resolving The Paradox Of Polyploidy: Underexplored Facets Of Polyploid Plants, Benjamin P. Gerstner

Biology ETDs

Polyploidy, or whole genome duplication, is a common phenomenon in plants, but the establishment and persistence of mixed-ploidy populations remains a paradox. This dissertation explores factors that contribute to the persistence and establishment of mixed-ploidy populations in nature. The first chapter investigates the role of unreduced gametes in neopolyploid establishment and finds that variability in their formation rate can have a significant impact on polyploid establishment and persistence. The second chapter searches for evidence of soil microbes exhibiting ploidy-specificity, a pre-condition for microbe-mediated niche differentiation, a possible stabilizing mechanism contributing to ploidy coexistence. Finally, the third chapter tests for microbe-mediated …

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