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Articles 301 - 330 of 5772

Full-Text Articles in Ecology and Evolutionary Biology

The Status Of Invasive Dusky Slug (Arion) Species In The Upper Great Lakes: A Molecular Approach, Olivia W. Hall Apr 2023

The Status Of Invasive Dusky Slug (Arion) Species In The Upper Great Lakes: A Molecular Approach, Olivia W. Hall

All NMU Master's Theses

I update the distribution of two cryptic slug species, Arion fuscus and Arion subfuscus, in the Upper Great Lakes of the United States using molecular identification methods. Arion fuscus has not previously been reported in the literature in this region, and Arion subfuscus has previously been reported as abundant. However, all previous distribution studies were determined using visual identification tools, which can result in misidentification between cryptic species. To molecularly re-examine these distribution maps, I used a mitochondrial ribosomal subunit 16S PCR amplification and subsequent SSpI and MfeI restriction enzyme digest to identify slug specimens. I collected slugs in …

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Testing For Relationships Between Animal Personality Traits, Activity Level And Voracity, And The Underlying Influence Of Body Size In The Dragonfly Predator, Epitheca Canis, Flynn Gorman Apr 2023

Testing For Relationships Between Animal Personality Traits, Activity Level And Voracity, And The Underlying Influence Of Body Size In The Dragonfly Predator, Epitheca Canis, Flynn Gorman

Senior Theses and Projects

Animal personality, defined as among-individual variation in behavior, is taxonomically widespread, but its ecological implications remain unclear. While associations between animal personality and ecological traits have been examined, methodological shortcomings, such as lack of repeated measurements, limit the insights these studies provide. Here, I measured the repeatability of activity level and feeding rate behaviors in the nymph stage of the dragonfly predator, Epitheca canis, taking 10 repeated measurements of each trait over a 10-week period. Moreover, I tested for a relationship between among-individual variation in activity level and feeding rate while accounting for the underlying influence of nymph body …

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Using Podcasts To Bring National Estuarine Research Reserves Into The Classroom For Grades 6-12, Kaitlyn M. Dirr Apr 2023

Using Podcasts To Bring National Estuarine Research Reserves Into The Classroom For Grades 6-12, Kaitlyn M. Dirr

Senior Theses

In a typical classroom setting, there are significant challenges to exposing students to concepts related to earth sciences and the environment. These challenges are exacerbated when conveying lessons about geographic areas with limited access, such as oceans and coastlines (Louv, 2010). It is now more important than ever for environmental education to improve and adapt to our changing world. Educators may have the opportunity to bring these subjects to life by using media content such as podcasts to introduce students to new places and the scientists, managers and educators that work in those spaces. In the United States, there exists …

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Movement, Behavior, And Trophic Ecology Of A Pelagic Predator Guild In The Eastern Tropical Pacific Ocean, Ryan Keith Logan Mar 2023

Movement, Behavior, And Trophic Ecology Of A Pelagic Predator Guild In The Eastern Tropical Pacific Ocean, Ryan Keith Logan

All HCAS Student Capstones, Theses, and Dissertations

Pelagic apex predators exert strong influences on ecological communities, and often support valuable commercial or recreational fisheries worldwide. Yet, due to their rarity and pelagic lifestyle, many species, such as billfishes, have proven particularly difficult to study at resolutions necessary to define dynamics of recovery from fishery interaction, physical interaction with environmental features and prey exploitation, and competitive interactions among other billfish predators. This leads to a paucity of knowledge on billfish ecology and habitat use, and hinders management efforts. With the ever-improving and miniaturization of technology and oceanographic datasets, the ability to define and quantify these interactions of fish …

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Lichens Of Ultramafic Rocks: A Multidisciplinary Approach To Understanding The Ecology Of An Understudied Organism In A Well-Studied System, Michael Mulroy Mar 2023

Lichens Of Ultramafic Rocks: A Multidisciplinary Approach To Understanding The Ecology Of An Understudied Organism In A Well-Studied System, Michael Mulroy

Master's Theses

Lichens are among the most prominent and successful life forms of metal-rich habitats, including ultramafic rocks and soils; however, research on lichens of ultramafic habitats is limited, especially on the North American continent. A review of the published literature on lichens of ultramafic substrates in North America yielded a total of 437 lichen species reported from ultramafic rocks and soils. Lichen assemblages of ultramafic substrates vary in composition and are dominated by acidophytic (low pH preferring) taxa with a minor, but consistent, basiphytic (high pH preferring) component. Species lists from ultramafic habitats in different geographic regions varied widely, suggesting that …

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American Eel (Anguilla Rostrata) And Other Fishes As Surveyed By Environmental Dna In The Bronx River And Hudson River Watershed, Sam C. Chin Feb 2023

American Eel (Anguilla Rostrata) And Other Fishes As Surveyed By Environmental Dna In The Bronx River And Hudson River Watershed, Sam C. Chin

Dissertations, Theses, and Capstone Projects

Mounting an effective response to the threats faced by freshwater fish may require expansions to aquatic biomonitoring in excess of what is feasible using the capture-based survey techniques currently relied upon by natural resource managers. Methods for analyzing environmental DNA (eDNA) are emerging as a minimally invasive and cost-effective approach for surveying fish and other organisms. By detecting taxon-specific DNA sequences recovered from environmental samples (e.g. water, sediment), eDNA methods are able to infer species presence from samples that can be collected rapidly with simple equipment. In many cases, eDNA detection rates of fish species have been shown to meet …

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What Drives Larval Condition For Northern Anchovy (Engraulis Mordax)? Implications For Coastal Pelagic Species Recruitment Fluctuations And Fishery Management Practices, Michelle Robidas Jan 2023

What Drives Larval Condition For Northern Anchovy (Engraulis Mordax)? Implications For Coastal Pelagic Species Recruitment Fluctuations And Fishery Management Practices, Michelle Robidas

Theses

Discerning the causes of population boom and bust cycles for coastal pelagic species (CPS) has been a major focus of fisheries management research for over a century. Year-class strength is contingent on larval survival and condition, which can be influenced by larval size at age and growth rate. These two factors, in turn, can be affected by maternal investment and environmental variables such as water temperature, salinity, oxygen, and chlorophyll a. We evaluated each of these factors from 127 two to eight week-old Northern Anchovy (Engraulis mordax) larvae off the coast of San Diego to San Francisco, …

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Controls Of Physical Drivers On The Formation And Toxicity Of Harmful Cyanobacteria Blooms (Cyanohabs), Courtney N. Hammond Jan 2023

Controls Of Physical Drivers On The Formation And Toxicity Of Harmful Cyanobacteria Blooms (Cyanohabs), Courtney N. Hammond

LSU Master's Theses

Estuaries within the Gulf of Mexico are exhibiting profound alterations due to climatic changes and the implementation of coastal restoration activities. These changes are attributed to the increasing frequency of harmful cyanobacteria blooms (cyanoHABs) within Lake Pontchartrain, an estuary located in southeastern Louisiana, USA. There is a better understanding into how the opening of the Bonnet Carré Spillway (BCS) impacts cyanoHAB formations compared to the effect of other physical drivers when the spillway doesn’t dominate the system. The goal of this study is to provide a greater understanding of the baseline conditions when the BCS is closed and determine what …

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National Development And The Sustainability Of Mining In The Atacama Desert, Chile, Dakota Soleil Osgood Jan 2023

National Development And The Sustainability Of Mining In The Atacama Desert, Chile, Dakota Soleil Osgood

Capstone Collection

As climate change continues to intensify on a global scale, efforts have been made to implement renewable energies and progressive technologies. These tools are critical in the shift towards a more sustainable practice, and yet analysis of localized impacts from the development of these mechanisms is inadequate. Chile has been and continues to be a leading country in mineral extraction, with an economic history founded in the mining industry. The establishment of mining in Chile as a progressive tool has aided the social and economic development of the nation. Consequences of mining extraction, however, include intensive environmental degradation, human rights …

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From Micro To Macro: Examining Potential Microbiome Mediated Influences On Human Growth And Health Outcomes Through Breastfeeding And Antibiotic Exposures, Nicole K. Phillips Jan 2023

From Micro To Macro: Examining Potential Microbiome Mediated Influences On Human Growth And Health Outcomes Through Breastfeeding And Antibiotic Exposures, Nicole K. Phillips

Electronic Thesis and Dissertation Repository

Human microbiome research has rapidly developed over the past two decades yet absent from most research is the composition and dynamics of microbiomes within human populations. Given the limitations in longitudinal studies which requires decades of repeated microbe taxonomic testing of a population sample, an alternative option is to examine microbiomes and their influences via proxies using pre-existing health datasets. This research demonstrates preliminary associations between presumed disrupted and supportive microbiomes dynamics proxied by antibiotic and breastmilk exposure respectively. Using health record data across the life span from approximately 500,000 U.K. participants, this research demonstrates variable altered growth and health …

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Assessing The Unionid Assemblage Of The Robert C. Byrd Pool, Ohio River, Ethan Hunter Bellamy Jan 2023

Assessing The Unionid Assemblage Of The Robert C. Byrd Pool, Ohio River, Ethan Hunter Bellamy

Theses, Dissertations and Capstones

Unionid mussels are the most imperiled taxa in the United States and are vastly understudied. The entire Robert C. Byrd (RCB) pool of the Ohio River is the study area. I selected sites from the 2019 and 2013 ORSANCO RCB pool assessments that utilize random site selection across the pool. I used SCUBA to survey and collect data on unionid diversity, reproduction, and habitat. I collected 1,083 individuals over 19 species in RCB pool. I compared results from RCB pool survey to two similar surveys conducted in Greenup Pool. Both richness and abundance in the Upper Section of Greenup Pool …

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Airborne Sound And Substrate-Borne Vibration In Orthopteran Communication, Ciara E. Kernan Jan 2023

Airborne Sound And Substrate-Borne Vibration In Orthopteran Communication, Ciara E. Kernan

Dartmouth College Ph.D Dissertations

The challenge of attracting and locating potential mates has driven the evolution of diverse mate-finding signaling systems. These systems can be complex, with multiple signals or signal components spread across different sensory modalities. When multiple modalities are combined in one communication system, features of each can be important to individual fitness; over evolutionary time, these can shape investment in different parts of a signal repertoire. One group of animals that commonly uses multiple signal modalities is Orthoptera. Cricket and katydid species within this order often produce airborne sound calls to advertise to potential mates. Many also produce substrate-borne vibrational signals. …

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Characterizing The Vegetation And Effects Of Climate Change On Parris Island, A Sea Island Ecosystem, Cody Hart Goodson Jan 2023

Characterizing The Vegetation And Effects Of Climate Change On Parris Island, A Sea Island Ecosystem, Cody Hart Goodson

Theses, Dissertations and Capstones

Coastal habitats provide many ecosystem services, protecting coastlines from storm surges and erosion, diminishing the effects of eutrophication, sequestering large amounts of carbon, and acting as vital wildlife habitat. Sea-level rise and increased storm surge intensity associated with climate change are increasingly disrupting coastal habitats. These disturbances can shift environmental gradients that drive the zonation of coastal vegetation types, driving habitat conversion. Monitoring coastal habitat conversion can improve our understanding of the dynamic effects of climate change on these landscapes. Therefore, our objectives for chapter 1 were to identify and describe the distributions of vegetation types present on Marine Corps …

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Gender Equality In Ocean Science For Sustainable Development : Analysis Of Ocean Science Institutions In Kenya, Renis Auma Ojwala Jan 2023

Gender Equality In Ocean Science For Sustainable Development : Analysis Of Ocean Science Institutions In Kenya, Renis Auma Ojwala

World Maritime University Ph.D. Dissertations

Gender inequality poses a serious problem for national and international developmental programmes such as the United Nations Decade of Ocean Science for Sustainable Development (the Ocean Decade) and appears in both developed and developing countries. The fundamental aim of the Ocean Decade is to improve ocean health worldwide through generating knowledge, supporting innovations, discovering creative ideas and developing solutions to achieve equitable and sustainable development under the changing environmental, social and climate conditions. The paucity of women in ocean management has been documented as a major hindrance to ocean sustainability and a top challenge to diversity in workplaces because of …

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Monitoring Movement And Range Expansion Of Silver And Bighead Carp (Hypophthalmichthys Molitrix, H. Nobilis) In South Dakota Tributaries Of The Missouri River, Lindsey Ann Pearl Labrie Jan 2023

Monitoring Movement And Range Expansion Of Silver And Bighead Carp (Hypophthalmichthys Molitrix, H. Nobilis) In South Dakota Tributaries Of The Missouri River, Lindsey Ann Pearl Labrie

Dissertations and Theses

Invasive species, climate change, human impacts on the landscape, flooding, and drought are all dynamic factors that greatly impact the Missouri River and its tributaries in eastern South Dakota. Invasive Carp, and more specifically, Bighead (Hypophthalmichthys nobilis) and Silver Carp (H. molitrix), first invaded the Missouri River watershed in eastern South Dakota in the late 1990s and have since spread throughout the basin downstream of Gavin’s Point Dam. The first chapter of this study uses environmental DNA (eDNA) in the context of two major barriers to fish movement in the Vermillion and Big Sioux Rivers to determine potential presence and …

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Biomechanics Of Mantis Prey Capture, Danielle S. Taylor Jan 2023

Biomechanics Of Mantis Prey Capture, Danielle S. Taylor

Honors Theses

Mantis species have a variety of different morphologies, so do the extreme forms of mantis limbs trade prey catching capability for camouflage? We hypothesize that some extreme forms of mantis limbs that are associated with cryptic species may be associated with a tradeoff of the capability of those limbs. Previous research has developed 2D morphologies of several hundred species of mantises. We are creating a 3D morphology by using micro dissection, micro CT imaging to construct our 3D biomechanical model. We found the attachment points of the ligaments and muscles from a Tenodera forearm and have constructed a 2D biomechanical …

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Belowground Plant Communities: Seed Bank Dynamics And Relationship To Aboveground Vegetation In Grazing Allotment Of Klamath County, Oregon, Dellaina C. Morse, Scott M. Estepa Jan 2023

Belowground Plant Communities: Seed Bank Dynamics And Relationship To Aboveground Vegetation In Grazing Allotment Of Klamath County, Oregon, Dellaina C. Morse, Scott M. Estepa

Environmental Science & Management Senior Capstones

Seed banks are valuable resources for restoration but are understudied. The species present in the aboveground composition influence the seed bank through seed inputs. Land managers utilize herbicides to selectively reduce certain species in the above- and belowground composition. The aim of this paper is to observe and assess the species present in a seed bank post-herbicide application, and to discuss the seed bank potential for future restoration at the specific site in Klamath County, Oregon. Soil core samples were collected in the field and brought to the lab where they were processed and prepared for germination. We watered and …

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Prevalence Of Hesperevax Sparsiflora Var. Brevifolia (Short-Leaved Evax) At Ocean Ranch, Humboldt County, California: Exploring The Effects Of Disturbance, Shelby Diquirco, Matthew Estrada, Alana T. Fraley, Alexander D. Smith Jan 2023

Prevalence Of Hesperevax Sparsiflora Var. Brevifolia (Short-Leaved Evax) At Ocean Ranch, Humboldt County, California: Exploring The Effects Of Disturbance, Shelby Diquirco, Matthew Estrada, Alana T. Fraley, Alexander D. Smith

Environmental Science & Management Senior Capstones

The prevalence of special-status plants within a landscape can be an indicator of the ecological health of that site, and therefore inform restoration efforts and post-restoration monitoring. Hesperevax sparsiflora var. brevifolia (short-leaved evax) is a special status species found within the Ocean Ranch unit of Humboldt, California. A primary threat to native plant communities are invasive plant species. Coastal dune ecosystems are largely dominated by invasive species, including Ammophila arenaria (European beachgrass). To work towards the eradication of A. arenaria, the California Department of Fish and Wildlife utilized treatment combinations of herbicide and prescribed fire at Ocean Ranch in …

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Estructura De La Comunidad Y Preferencia De Escarabajos Cyclocephalini (Coleoptera: Dynastinae) Visitantes Florales De Palmeras Silvestres En Casanare, Orinoquía Colombiana, Daniel Leonardo Buitrago Calderón Jan 2023

Estructura De La Comunidad Y Preferencia De Escarabajos Cyclocephalini (Coleoptera: Dynastinae) Visitantes Florales De Palmeras Silvestres En Casanare, Orinoquía Colombiana, Daniel Leonardo Buitrago Calderón

Biología

Las especies de escarabajos Cyclocephalini (Dynastinae), se han reportado como visitantes florales en diversas familias de angiospermas, la visita está relacionada con el aprovechamiento de recursos florales y lugar de apareamiento, polinizando las flores femeninas de estas plantas cuando entran en contacto con las estructuras reproductivas cargados de polen; su rol ecológico y asociación con especies de palmeras ha sido debatido recientemente dado que, a diferencia de lo que se pensaba, en la actualidad se han reportado como polinizadores ineficientes y altamente polinivoros en las inflorescencias, además de la poca disponibilidad de colecciones de referencia de la tribu en Colombia …

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An Analysis Of The Preferences, Morphometrics, And Survey Efficacy Of The Freshwater Mussel Community In The Greenup Pool, Ohio River, Jacob Miller Jan 2023

An Analysis Of The Preferences, Morphometrics, And Survey Efficacy Of The Freshwater Mussel Community In The Greenup Pool, Ohio River, Jacob Miller

Theses, Dissertations and Capstones

The Greenup Pool is one of the most unique pools of the Ohio River in terms of habitat richness and anthropogenic impact both historical and current. The Greenup Pool spans 61.8 miles reaching from Greenup Dam in Greenup, KY to Robert C. Byrd Dam in Apple Grove, WV. We surveyed 17 sites to assess mussel communities within the Greenup Pool using the 2017 West Virginia Mussel Survey Protocol. At these sites, six 100-meter transects were surveyed for surface and subsurface mussels. Each transect was divided into 10-meter intervals. These surveys resulted in 4,041 live individuals from 21 species, including eight …

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Spatiotemporal Analyses Of Pelagic Sargassum : Biodiversity, Morphotypes And Arsenic Content, Kristie Alleyne Jan 2023

Spatiotemporal Analyses Of Pelagic Sargassum : Biodiversity, Morphotypes And Arsenic Content, Kristie Alleyne

World Maritime University Ph.D. Dissertations

Pelagic sargassum blooming in the Tropical Atlantic has been linked to the mass shoreline inundations observed over the last decade in Caribbean and West African countries. Since the onset in 2011, affected countries have and continue to experience multiscale impacts across fisheries, tourism, nearshore coastal ecosystems, maritime transport and public health. Impacts associated with influx events have generated significant economic damage across the region. Moreover, clean-up efforts in response to mass shoreline strandings placed further strain on national economies and in some instances amplified the negative environmental effects caused by inundations. Evidence suggests that influx events are likely to continue …

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Assessing The Need For Harmonized Marine Debris Monitoring And Equity To Support Participation In The Global Plastics Treaty Negotiations By Caribbean Sids, Kristal Ambrose Jan 2023

Assessing The Need For Harmonized Marine Debris Monitoring And Equity To Support Participation In The Global Plastics Treaty Negotiations By Caribbean Sids, Kristal Ambrose

World Maritime University Ph.D. Dissertations

This research addresses the challenge of marine plastic pollution with particular reference to Caribbean Small Island Developing States (SIDS). Marine plastic pollution is of particular significance to these states since they suffer from a disproportionate incidence of plastic pollution on their coasts. In line with the region's need to protect its marine environment and subsequently its economy from the grave impacts of plastic pollution, this work assesses marine debris monitoring within Caribbean SIDS, and the barriers faced and considerations needed for unified monitoring efforts that support policy development. Additionally, the research examines microplastics on the beaches of Caribbean SIDS, and …

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Combatting The Marine Litter Crisis In The Windward Islands : Examining Source-To-Sea Pathways And Fostering Multi-Scale Solutions, Roxanne Elizabeth Donna Graham Jan 2023

Combatting The Marine Litter Crisis In The Windward Islands : Examining Source-To-Sea Pathways And Fostering Multi-Scale Solutions, Roxanne Elizabeth Donna Graham

World Maritime University Ph.D. Dissertations

This research investigates the intricate and all-pervasive challenge of combatting marine litter in small island developing states (SIDS), specifically in the Wider Caribbean Region (WCR) with a focus on the understudied Windward Islands located in the south-east of the Caribbean. Notably, this research is a ground- breaking and innovative effort in several respects, marking the first time a study of such magnitude and depth has been conducted and published for the WCR and the Windward Islands in particular. This pioneering work thus not only fills a significant gap in the existing literature but also sets a benchmark for future studies …

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Characterization Of The Mycobiome Of Rafflesia Seeds: Their Potential Ecological Roles And Applications In Rafflesia Propagation And Conservation, Feruza Karnitskiy Jan 2023

Characterization Of The Mycobiome Of Rafflesia Seeds: Their Potential Ecological Roles And Applications In Rafflesia Propagation And Conservation, Feruza Karnitskiy

Selected Full-Text Master Theses 2021-

The plant microbiome exerts a profound influence on plant health, growth, and life cycle. This ecosystem comprises diverse microbial communities, such as symbiotic endophytes, mycorrhizal fungi, epiphytes, saprophytes, rhizobia, and pathogens, which inhabit parasitic and non-parasitic plants. Rafflesia speciosa, a holoparasitic plant, is a unique and endangered species that depends on its host Tetrastigma spp. for survival. In this study, fungal metagenomics was conducted to characterize the fungal community—the mycobiome within Rafflesia seeds, and a phylogeny was reconstructed. The ecophysiological characteristics of these fungal genera were also researched in the literature, and their primary ecological trait, whether plant mutualist, saprotroph, …

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Application Of Hierarchical Species Distribution Models To Avian Species Of South Dakota And The Upper Missouri River Basin, Reza Goljani Amirkhiz Jan 2023

Application Of Hierarchical Species Distribution Models To Avian Species Of South Dakota And The Upper Missouri River Basin, Reza Goljani Amirkhiz

Dissertations and Theses

Recognizing the distributional patterns of species can inform management actions and increase scientific knowledge about species. Habitat Suitability Models (HSMs) are valuable tools in modeling species’ niches and effects of climate change and anthropogenic and natural disturbances on species’ distributions and abundances. In this dissertation, I expanded the application of hierarchical HSMs for a rare bird (Virginia’s warbler) and an economically valuable bird (ring-necked pheasant) in South Dakota. Also, we developed multiscale HSMs for grassland birds in the Upper Missouri River Basin (UMRB) to quantify current habitat associations and predict the influences of climate and landcover change associated with the …

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Csi Botany: Dna Barcode “Fingerprints” Identify Cryptic Urban Flora, Luis R. Vega Jan 2023

Csi Botany: Dna Barcode “Fingerprints” Identify Cryptic Urban Flora, Luis R. Vega

Theses

As short genomic markers, DNA barcodes can play a role in conservation by identifying cryptic species and hybrids when morphological approaches fall short. Here we present our application of barcodes to the identities of two wetland taxa as part of an ongoing floristic inventory of Van Cortlandt Park (VCP), Bronx, NY. Previous barcode data by Marriott et al. (2018) identified the VCP lake water lily as the exotic Nymphaea alba, rather than the native N. odorata as historically described. In addition, cattails in the park were historically identified as the native Typha latifolia and the exotic T. angustifolia …

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Biogeography Of Special Metabolites Produced By Ant-Associated Bacteria, Katherine Hansen Jan 2023

Biogeography Of Special Metabolites Produced By Ant-Associated Bacteria, Katherine Hansen

Scripps Senior Theses

There is an urgent and growing need for novel antibiotics with the growing prevalence of antibiotic-resistant pathogens. Ecologically-guided discovery is a strategy that focuses on how and where specially evolved metabolites such as antibiotics are used in nature. This strategy reveals unique active molecules with potential for human use. An unexplored niche with great potential for antibiotic discovery exists with Southwestern fungus-farming Trachymyrmex ants and their Actinobacteria symbionts. In exchange for nutrients from the ant, the ants’ bacterial symbiont produces antifungal molecules that protect the ants’ fungal cultivar from invasion by pathogenic microorganisms. They also produce antibacterial molecules to protect …

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Empirical Valuation Of Primary And Alternative Nursery Habitats For The Blue Crab Callinectes Sapidus In Chesapeake Bay, Alexander C. Hyman Jan 2023

Empirical Valuation Of Primary And Alternative Nursery Habitats For The Blue Crab Callinectes Sapidus In Chesapeake Bay, Alexander C. Hyman

Dissertations, Theses, and Masters Projects

The blue crab (Callinectes sapidus) is a commercially and ecologically importantspecies found along the Atlantic coast of North and South America. These crustaceans play a critical role in coastal ecosystems, serving as both predators and prey in the food web. The blue crab supports a major fishery in Chesapeake Bay, where the species is a cultural icon. Juvenile blue crabs, the smallest and most vulnerable size classes of individuals, are reliant upon structurally complex habitats. Population dynamics of this species are therefore influenced by spatiotemporally fluctuating environmental variables, such as habitat availability. Understanding blue crab ecology is essential for managing …

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Relationships Between Watershed Factors And Community Size Spectra Of The Fish And Macroinvertebrate Communities Of Mid-Appalachian Streams, Jarrett Hunter Landreth Jan 2023

Relationships Between Watershed Factors And Community Size Spectra Of The Fish And Macroinvertebrate Communities Of Mid-Appalachian Streams, Jarrett Hunter Landreth

Graduate Theses, Dissertations, and Problem Reports

Freshwater lotic communities are complex, dynamic, and quick to respond to changes to their environment. However, some of the specific mechanisms driving those changes are yet to be fully understood. Here, I will use the community size spectrum (CSS) approach to assess how the CSS slope, elevation, and food chain length of the fish and macroinvertebrate assemblages as well as the combined CSS of 15 mid-sized (2nd-4th order) streams in north-central West Virginia respond across gradients of watershed factors (drainage area, mean drainage slope, mean drainage elevation, drainage % forest, and stream specific conductance). Field sampling was carried out in …

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Under Ice Photosynthetic Primary Production And Dark Carbon Fixation In A Temperate Freshwater System, Vanessa Cubillos Tellez Jan 2023

Under Ice Photosynthetic Primary Production And Dark Carbon Fixation In A Temperate Freshwater System, Vanessa Cubillos Tellez

Dissertations, Master's Theses and Master's Reports

Ice-covered lakes are vulnerable to environmental change, especially those in the Northern Hemisphere where ice cover is rapidly declining due to global warming. These changes can alter metabolic processes and disrupt carbon cycling driven by primary producers who form the base of the food chain and are key to sustaining ecosystem function. Photosynthetic primary production and dark carbon fixation under the ice in the Keweenaw Waterway, a temperate freshwater system that is ice-covered for ~3 months out of the year, were studied using a carbon isotopic labeling (14C-bicarbonate) technique. Water samples were collected weekly during ice cover and monthly during …

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