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Full-Text Articles in Biology

Todaro Channeled Apple Snail (Pomacea Canaliculata), Jasmyn Todaro, Amy C. Hirons Nov 2024

Todaro Channeled Apple Snail (Pomacea Canaliculata), Jasmyn Todaro, Amy C. Hirons

Hirons Field Techniques

Channeled Apple Snail (Pomacea canaliculata) shell.


Bodine: An Agent-Based Modeling Approach To Studying Localized Coexistence Across Environmental Heterogeneity, Alexandra Campbell Nov 2024

Bodine: An Agent-Based Modeling Approach To Studying Localized Coexistence Across Environmental Heterogeneity, Alexandra Campbell

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Structural Molecular And Developmental Evidence For Cell-Type Diversity In Cnidarian Mechanosensory Neurons, Julia Baranyk, Kristen Malir, Miguel A.P. Silva, Sakura Rieck, Gracie Scheve, Nagayasu Nakanishi Nov 2024

Structural Molecular And Developmental Evidence For Cell-Type Diversity In Cnidarian Mechanosensory Neurons, Julia Baranyk, Kristen Malir, Miguel A.P. Silva, Sakura Rieck, Gracie Scheve, Nagayasu Nakanishi

Biological Sciences Faculty Publications and Presentations

Deploying a conserved mechanosensory neuron known as the concentric hair cell, cnidarians have evolved diverse mechanoreceptors from hydroid filiform tentacles to jellyfish statocysts. However, it is unknown whether cnidarian mechanoreceptor evolution has relied solely on repurposing a single ancestral mechanosensory neuron type. Here we report evidence for cell-type diversity of mechanosensory neurons in sea-anemone cnidarian Nematostella vectensis. Uncovered in the ectoderm of feeding tentacles are conventional type I hair cells and previously unrecognized type II hair cells differing in the structure of apical sensory apparatus and synapses. Moreover, we identify TRP channel-encoding gene polycystin-1 as a type-II-hair-cell-specific essential mediator of …


What Drives Gut Microbial Diversity And Community Structure Among Closely-Related Host Species?, Rylee Jensen Nov 2024

What Drives Gut Microbial Diversity And Community Structure Among Closely-Related Host Species?, Rylee Jensen

All NMU Master's Theses

The gut microbiome (GMB) of mammals hosts an important community of microbes that perform countless micro-ecosystem services for the host and are influenced by numerous factors including host physiology, environment, and phylogeny. Phylogeny may have a unique effect on GMB diversity and community structure (i.e., a GMB profile) via phylosymbiosis, a theory in which the evolution of hosts matches the evolution of their associated microbiota. Elucidating phylosymbiosis in mammals is difficult because multiple intrinsic and extrinsic factors collectively drive individual GMB variation. Thus, there is a need to simultaneously analyze the role of physiology, environment, and phylogeny on shaping host …


The Divergent Responses Of Salinity Generalists To Hyposaline Stress Provide Insights Into The Colonisation Of Freshwaters By Diatoms, Kathryn J. Judy, Eveline Pinseel, Kala M. Downey, Jeffrey A. Lewis, Andrew J. Alverson Nov 2024

The Divergent Responses Of Salinity Generalists To Hyposaline Stress Provide Insights Into The Colonisation Of Freshwaters By Diatoms, Kathryn J. Judy, Eveline Pinseel, Kala M. Downey, Jeffrey A. Lewis, Andrew J. Alverson

Biological Sciences Faculty Publications and Presentations

Environmental transitions, such as the salinity divide separating marine and fresh waters, shape biodiversity over both shallow and deep timescales, opening up new niches and creating opportunities for accelerated speciation and adaptive radiation. Understanding the genetics of environmental adaptation is central to understanding how organisms colonise and subsequently diversify in new habitats. We used time-resolved transcriptomics to contrast the hyposalinity stress responses of two diatoms. Skeletonema marinoi has deep marine ancestry but has recently invaded brackish waters. Cyclotella cryptica has deep freshwater ancestry and can withstand a much broader salinity range. Skeletonema marinoi is less adept at mitigating even mild …


Effects Of Retinal Gonadotropin-Releasing Hormone On Reproductive Behavior And Retinal Activity In The Cichlid Fish, Astatotilapia Burtoni, Chase Anselmo Oct 2024

Effects Of Retinal Gonadotropin-Releasing Hormone On Reproductive Behavior And Retinal Activity In The Cichlid Fish, Astatotilapia Burtoni, Chase Anselmo

LSU Master's Theses

Many animals use visual signals to evade predators, forage for food, and communicate with conspecifics. Some animals that shift into and out of breeding stages, such as fish, can modulate their visual sensitivity to better adapt to changing internal and external conditions. Previous work in our lab demonstrated that females of the cichlid fish Astatotilapia burtoni have improved visual sensitivity when they enter reproductive readiness. However, little is known about how fish and vertebrates more broadly modulate visual sensitivity across their reproductive cycle. We hypothesized that the hormone and neuromodulator gonadotropin-releasing hormone (GnRH) could modulate visual sensitivity because GnRH is …


Temperature Affects Nest Box Selection, Nest Success, And Nestling Size In A Southeastern Population Of Eastern Bluebirds, Katie Stumpf Oct 2024

Temperature Affects Nest Box Selection, Nest Success, And Nestling Size In A Southeastern Population Of Eastern Bluebirds, Katie Stumpf

Georgia Journal of Science

Given the critical role of temperature in avian reproduction, rising global temperatures will likely impact reproductive success of many bird populations. We examined the effect of nest box temperature, nest box color, entrance orientation, distance to forest cover, and distance to water on net box selection, nest success, and nestling size in eastern bluebirds (Sialia sialis) in central Georgia. White painted nest boxes had significantly cooler temperatures than control nest boxes (P < 0.05). However, model selection revealed that eastern bluebird females selected control boxes, despite their overall warmer temperatures. Nest success was associated with year, likely because of high nest predation during the warmer 2022 breeding season (P < 0.05). Nest success was also associated with cooler nest boxes, possibly because incubating females spend more time incubating which can reduce predation risks. Larger nestlings fledged from painted nest boxes, nest boxes with cooler temperatures, and nests from 2021, which we attribute to decreased thermoregulatory demands enabling faster nestling growth in cooler boxes and years. These seemingly opposing results suggest there may be an optimal temperature range where nest box temperature maximizes reproductive fitness while minimizing energetic demands on incubating adults. Determining this temperature range can help target management efforts to ensure specific goals are met.


Ophidiomyces Ophidiicola And Texas Snakes: A Field To Bench Study Of Ophidiomycosis, Kenlynn L. Volz Oct 2024

Ophidiomyces Ophidiicola And Texas Snakes: A Field To Bench Study Of Ophidiomycosis, Kenlynn L. Volz

Biology Theses

Ophidiomyces ophidiicola (Oo), the primary cause of Ophidiomycosis, is a fungal pathogen recently detected in Texas snakes. Prior to this study, there were major knowledge gaps regarding Oo growth, spread, and suitable environmental conditions. This study filled those gaps using a field to bench approach involving sampling snakes across Texas, in vitro fungal growth, and ecological niche modeling. 103 snakes were sampled across Texas in 2023 and 2024 and six cases of Oo infection were detected. Results of the growth experiment suggest that Oo prefers more stable temperatures and high humidity to a point and that there is a …


Monitoring The Seasonal Presence Of The Blue Shiner, Cyprinella Caerulea, In Little River Canyon National Preserve Using Environmental Dna, Deanna Meadows Oct 2024

Monitoring The Seasonal Presence Of The Blue Shiner, Cyprinella Caerulea, In Little River Canyon National Preserve Using Environmental Dna, Deanna Meadows

Theses

The study of environmental DNA (eDNA) has provided researchers with a more accessible and sensitive way to identify the presence of specific species compared to traditional monitoring methods. eDNA enables species detection by analyzing environmental samples such as water or soil, which contain genetic material shed by organisms in a given area. Research indicates that eDNA techniques have become a valuable method for monitoring threatened and invasive species, proving particularly reliable for detecting aquatic species compared to traditional techniques. Quantitative PCR (qPCR) has been used in numerous eDNA studies, as it provides for greater accuracy than conventional PCR. Cyprinella …


Field-Based Courses Still Matter, But Not Like They Used To, Christopher T. Martine Oct 2024

Field-Based Courses Still Matter, But Not Like They Used To, Christopher T. Martine

Faculty Journal Articles

Increasingly, field-based courses are providing the first real opportunities for students to experience nature in meaningful ways. As a baseline, even before the content delivery and the graded assessments, this is already enough to change the way a person feels in the world and to spark an appreciation for the life around them.

(Part of a special feature on education in which recent winners of the Botanical Society of America's Charles E. Bessey Award share teaching philosophies and strategies.)


A Dendrochronological Analysis Of Longleaf And Associated Pines From The Blackwater Ecological Preserve In Southeastern Virginia, Sarah Durham Oct 2024

A Dendrochronological Analysis Of Longleaf And Associated Pines From The Blackwater Ecological Preserve In Southeastern Virginia, Sarah Durham

Biological Sciences Theses & Dissertations

The field of dendrochronology utilizes annual tree ring growth data to create chronologies, which function as proxies to measure the effect of climate on radial growth. In the southeastern United States, dendrochronological studies involving the effect of climate on the growth of Pinus species exist, but significant gaps persist. For this study, I: 1) created chronologies of earlywood, latewood, and total ring-width growth for longleaf pine (Pinus palustris Mill.), loblolly pine (P. taeda L.), and pond pine (P. serotina Michx.) and 2) conducted a climate analysis on each species to determine how climatic factors affected radial …


Montane Molluscs: Factors Affecting Snails And Their Trematodes Throughout The Mountain Regions Of Arkansas, Taylor Michelle Fiedor Sep 2024

Montane Molluscs: Factors Affecting Snails And Their Trematodes Throughout The Mountain Regions Of Arkansas, Taylor Michelle Fiedor

Student Theses and Dissertations

Spatial processes across both broad and fine scales are important for understanding ecosystem function. Broad-scale spatial processes can be defined as elevational, latitudinal, or longitudinal processes whereas fine-scale spatial processes represent movement and dispersal among habitat patches. Historically, studies on freshwater snail distributions have focused on fine-scale processes with secondary consideration given to spatial sampling. Species inventories for freshwater snails are outdated because historically snail species descriptions were based on shell morphology, which is highly plastic. In Arkansas, it is estimated that there are 36 freshwater snail species, but this estimate does not account for shell plasticity and does not …


Pilbara Demersal Scalefish Resource Recovery Plan 2023- 2043 (Phase 1), Department Of Primary Industries And Regional Development, Western Australia Sep 2024

Pilbara Demersal Scalefish Resource Recovery Plan 2023- 2043 (Phase 1), Department Of Primary Industries And Regional Development, Western Australia

Fisheries Management Papers

The Pilbara Demersal Scalefish Resource (PDSR) includes over 60 demersal scalefish species. The resource is accessed by the Pilbara Trap Managed Fishery, Pilbara Fish Trawl (Interim) Managed Fishery, and the Pilbara Line Fishery (PTMF, PFTIMF & PLF respectively) as well as the recreational and charter fisheries.

The PDSR is managed in accordance with the North Coast Demersal Scalefish Resource Harvest Strategy (Harvest Strategy). The sustainability objectives of the PDSR are set out in the Harvest Strategy and monitored via the use of an indicator species approach, whereby the status of key species is considered representative of the status of the …


Louisiana Graduate Network In Applied Evolution (Lagniappe): 2023-2024 End-Year Report, Kristina Little, Samuel B. Robison, Bret Blackmon, Andrew R. Burns Sep 2024

Louisiana Graduate Network In Applied Evolution (Lagniappe): 2023-2024 End-Year Report, Kristina Little, Samuel B. Robison, Bret Blackmon, Andrew R. Burns

Reports

The Louisiana Graduate Network in Applied Evolution (hereinafter; LAGNiAppE) was funded by a grant awarded through the National Science Foundation (NSF 22-506), as part of the Research and Mentoring for Postbaccalaureates in Biological Sciences (RaMP) grant program. The LAGNiAppE program provides training and mentorship to cohorts of recent college graduates from underrepresented groups interested in advancing their knowledge and research skills in evolutionary biology. Social Research and Evaluation Center (SREC) at Louisiana State University conducted the evaluation of LAGNiAppE, assessing program implementation and impact. The evaluation team at SREC employed a mixed methods design that included online surveys for scholars …


From Turf To Turf: Fungal Invasion Of Ascocoryne Turficola In A Northern Michigan Bog, Evan L. Coscarelli-Trott Sep 2024

From Turf To Turf: Fungal Invasion Of Ascocoryne Turficola In A Northern Michigan Bog, Evan L. Coscarelli-Trott

All NMU Master's Theses

This is the first paper to report Ascocoryne turficola Boud. 1905 (Helotiales: Ascomycota) within the United States. It is an obligate bog fungus native to Europe and Siberia, where it is extremely rare across most of its range. A. turficola appeared at Lily Pond Bog in Marquette, Michigan (87.47º W, 46.59º N) in 2019, almost contemporaneous with anecdotal reports in Minnesota and Ontario. Since 2019, the Lily Pond population has exploded and become the dominant fungus in this bog but has yet to spread to similar bogs nearby. This species is adapted to long distance dispersal and carries the potential …


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 …


Variability In Associations Among Seabirds And Marine Mammals: Causes And Consequences, Samantha A. Monier Sep 2024

Variability In Associations Among Seabirds And Marine Mammals: Causes And Consequences, Samantha A. Monier

Dissertations, Theses, and Capstone Projects

Marine predators today face multifaceted stressors from changing climate to changing prey availability, and these changes are occurring at unprecedented speeds. Any alteration to a species’ environment has the potential to disrupt social networks and thus, how animals obtain and transfer information. Interspecific social interactions in the form of local enhancement and facilitation are a critical, but not yet well-understood, component of seabird foraging; of immediate concern is that anthropogenic changes may be altering the quantity and quality of positive species interactions, with consequences for the species involved.

While we know these interactions are not immutable, less is known about …


Population Genetic Diversity In Two Biological Systems, Alyson Emery Aug 2024

Population Genetic Diversity In Two Biological Systems, Alyson Emery

Electronic Theses and Dissertations

Population genetic analysis can be used to answer questions about population structure and composition in many biological systems. Recent improvements to sequencing technologies have made population genetic studies more accessible than ever before. Many of the same techniques can be applied to different biological systems, but some analyses may differ depending on how genetically divergent the populations in question are. Here, we describe two unique projects using next-generation genome sequencing, each looking at population structure at different levels of genetic divergence: the first involved determining interspecific population structure between two species of hybridizing field cricket using a novel sequencing method, …


Phylotranscriptomic Relationships Of The Oophila Clade Of Green Algae Associated To Amphibian Egg Masses, Ryan Kerney, Miguel Vences, Maria Sachs, Iker Irisarri, Fabian Bartels, Pontus Eriksson, Sven Künzel, Atsushi Kurabayashi, Ane Laugen, Zachary Vegso, Cory Bishop, Hartmut Arndt Aug 2024

Phylotranscriptomic Relationships Of The Oophila Clade Of Green Algae Associated To Amphibian Egg Masses, Ryan Kerney, Miguel Vences, Maria Sachs, Iker Irisarri, Fabian Bartels, Pontus Eriksson, Sven Künzel, Atsushi Kurabayashi, Ane Laugen, Zachary Vegso, Cory Bishop, Hartmut Arndt

Biology Faculty Publications

Green algae usually assigned to the genus Oophila are known to colonize egg capsules of amphibian egg masses across the Nearctic and Palearctic regions. We study the phylogenetic relationships of these algae using a phylotranscriptomic data set of 76 protein-coding single-copy nuclear genes. Our data set includes novel RNAseq data for six amphibian-associated and five free-living green algae, and draft genomes of two of the latter. Within the Oophila clade (nested within Moewusinia), we find samples from two European frogs (Rana dalmatina and R. temporaria) closely related to those of the North American frog R. aurora (Oophila …


The Effects Of People, Time Of Day, And Season On Affiliative And Stereotypic Behaviors In Captive Rhinoptera Bonasus And Other Rays Across Two Human-Interactive Enclosures, Wren C. A. Newman Aug 2024

The Effects Of People, Time Of Day, And Season On Affiliative And Stereotypic Behaviors In Captive Rhinoptera Bonasus And Other Rays Across Two Human-Interactive Enclosures, Wren C. A. Newman

Theses and Dissertations

Cownose rays (Rhinoptera bonasus) are among the most common species found in aquaria, yet the impact of touch enclosures on their welfare remains largely unknown. While research on animal-visitor interactions has produced mixed results for other species, the lack of studies focusing on fish welfare poses a risk of overlooking potential welfare concerns. Therefore, we aimed to establish a baseline for cownose rays regarding stereotypic behaviors, sociality, and activity in captivity, and to examine the influence of human interaction on these behaviors. We collected over 700 hours of footage from two enclosures at Adventure Aquarium in Camden, NJ …


The Evolution Of A Response To Smoke Within The Arthropoda, Adam Miles Aug 2024

The Evolution Of A Response To Smoke Within The Arthropoda, Adam Miles

Masters Theses & Specialist Projects

Many animals have a survival instinct to flee in response to fire, but do they respond to smoke alone? Many arthropods respond to fire or smoke by moving in the opposite direction (a negative taxis) to obtain shelter. At the species level, taxa that have adapted a behavioral response to fire increase their fitness. This response behavior has been observed in many terrestrial arthropods. Still, the behavior is currently unknown for marine, aquatic, or cave arthropods, which are atypically exposed to smoke or fire. This project assesses how often behavioral adaptation to smoke avoidance may have evolved within Arthropoda. Twenty-two …


Shifting Paradigms In Recreation Management: Applying Social-Ecological System Frameworks To Parks And Protected Areas, Noah Creany Aug 2024

Shifting Paradigms In Recreation Management: Applying Social-Ecological System Frameworks To Parks And Protected Areas, Noah Creany

All Graduate Theses and Dissertations, Fall 2023 to Present

Park and protected area (PPA) recreation management is often characterized by social, ecological, and managerial dimensions. These dimensions have increasingly been conceptualized as social-ecological systems (SESs) to understand the complex interrelationships between them. Contemporary trends of increased visitation on public lands in the United States, including US National Parks, have accentuated the complex interactions between the amount of recreation use, the capacity of the setting, the quality of the visitor experience, and ecological resource conditions. These challenges of managing recreation use and understanding these interactions will be further compounded by climate change and its effects on ecosystem composition and dynamics. …


Unraveling The Behavioral Ecology Of The Western Diamond-Backed Rattlesnake (Crotalus Atrox) Through The Lenses Of Personality, Predator-Prey Interactions, And Crypsis, Oceane Da Cunha Aug 2024

Unraveling The Behavioral Ecology Of The Western Diamond-Backed Rattlesnake (Crotalus Atrox) Through The Lenses Of Personality, Predator-Prey Interactions, And Crypsis, Oceane Da Cunha

Open Access Theses & Dissertations

To thrive in an environment, individuals need to be able to forage efficiently and acquire mates. These resources are limited, and their acquisition depends upon the energy and time an individual chooses to allocate to each activity and the environmental conditions, leading to behavioral trade-offs. Different species, or even different individuals within the same population, respond to these trade-offs by employing contrasting strategies, leading to differential life-history outcomes. The overarching goal of this dissertation is to gain a better understanding of the trade-offs cryptic ambush mesopredators are facing using the western diamond-backed rattlesnake (Crotalus atrox) as a model species. Each …


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 …


Avian Communities Monitored Along A Successional Chronosequence In Bottomland Hardwood Forests In The Lower Mississippi Alluvial Valley, Eamonn Alasdair Thurmond Aug 2024

Avian Communities Monitored Along A Successional Chronosequence In Bottomland Hardwood Forests In The Lower Mississippi Alluvial Valley, Eamonn Alasdair Thurmond

Electronic Theses and Dissertations

Bottomland hardwood forests in the Lower Mississippi Alluvial Valley have been extensively reduced due to agriculture conversion and altered hydrology. Remnant forests have undergone further degradation from sources such as a lack of forest management, invasive species, and reduced regeneration of oaks (Quercus spp.). Recent restoration efforts of bottomland hardwood forests have focused on implementing wildlife forestry practices that prioritize restoring wildlife habitat while retaining profitable timber harvests. In this study I surveyed bird communities in bottomland hardwood forests in the Lower Mississippi Alluvial Valley along a successional chronosequence. Birds were sampled using automated recording units over 10 days …


Uvc And Planetary Habitability: Insights From Desert Lichens And Cyanobacteria, Tejinder Singh Aug 2024

Uvc And Planetary Habitability: Insights From Desert Lichens And Cyanobacteria, Tejinder Singh

UNLV Theses, Dissertations, Professional Papers, and Capstones

An important question in astrobiology is whether life can exist under the levels of UVC radiation found on Archean Earth, Mars, and exoplanets. We investigated this question by studying the UVC survival of colonial cyanobacterium and lichens that grow in harsh desert environments and possess natural sunscreens. We irradiated them nonstop in a desiccated state with a UVC flux closely representing the upper limit on those planets: 55-60 W/m². After irradiation, we rehydrated and assessed their survival using chlorophyll fluorometry and by counting the number of viable colonies that formed on agar plates. All three study organisms survived two to …


Impacts Of Anthropogenic Disturbances And Urbanization On The Behavior And Morphology Of Two Free-Living Lizard Species (Uta Stansburiana And Aspidoscelis Neotesselatus), Layne O. Sermersheim Aug 2024

Impacts Of Anthropogenic Disturbances And Urbanization On The Behavior And Morphology Of Two Free-Living Lizard Species (Uta Stansburiana And Aspidoscelis Neotesselatus), Layne O. Sermersheim

All Graduate Theses and Dissertations, Fall 2023 to Present

Urbanization can alter wildlife, requiring species to adjust to anthropogenic changes via life history strategies. Reptiles are particularly vulnerable to these changes, as ectotherms directly rely on their environment to maintain their optimal homeostatic state. As urbanization changes the landscape, reptiles will have to adapt to anthropogenic change, but it is unclear what behaviors may be aiding in this adaptation and whether there are morphological tradeoffs existing to support this change. To analyze the impact of urbanization and anthropogenic disturbances on reptile behavior and morphology, I conducted three research studies on two different species – the common side-blotched lizard and …


Influence Of Invasive Species, Drought, And Stream Permanence On Stream Crayfish Species With A Focus On The Imperiled Mammoth Spring Crayfish (Faxonius Marchandi), Leah Marie Bayer Aug 2024

Influence Of Invasive Species, Drought, And Stream Permanence On Stream Crayfish Species With A Focus On The Imperiled Mammoth Spring Crayfish (Faxonius Marchandi), Leah Marie Bayer

Graduate Theses and Dissertations

Freshwater crayfish constitute one of the most-threatened taxonomic groups in North America. Invasion by other crayfish species as well as habitat degradation through alteration of natural flow regime are two of the most prominent threats to crayfish persistence. Additionally, extreme weather events like droughts can amplify threats posed by other stressors on crayfish populations and are expected to increase in frequency, magnitude, and/or duration in the future, which may negatively influence narrow-ranged endemic crayfish populations typical of the Southeast. The Mammoth Spring Crayfish, Faxonius marchandi, is a narrow-ranged endemic that occurs in the Spring River drainage of Arkansas and Missouri …


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 …


Venom Complexity Within Garter Snakes And The Role Of Diet In Toxin Diversification, Tucker Heptinstall Aug 2024

Venom Complexity Within Garter Snakes And The Role Of Diet In Toxin Diversification, Tucker Heptinstall

All Theses

Complex traits, such as body size and venom, are often under strong selection by

dietary ecology and can increase efficiency of prey capture and processing. To investigate relationships between ecology and trait evolution in Thamnophis, we amassed nearly 10,000 diet records for 32/35 Thamnophis species and classified each species’ dietary repertoire. We categorized 15/32 species as generalist predators and 17/32 species as specialist predators of varying prey groups and investigated the hypothesis that generalist predators have larger body size. However, we found no significant relationship between body size and dietary specialization. Venom has evolved over 100 times across the Tree …