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Using Wasp Specimens In Taxonomic, Biogeographic, Evolution, And Informal Education Studies, Brenna Lynn Decker Aug 2024

Using Wasp Specimens In Taxonomic, Biogeographic, Evolution, And Informal Education Studies, Brenna Lynn Decker

All Graduate Theses and Dissertations, Fall 2023 to Present

Entomology collections hold an untapped wealth of information, from insect morphology, genetics, locality and association data, and potential for use in education. Especially with insects that generate initial fears, such as wasps, seeing insect specimens provides a safe environment to learn about their behaviors. Wasps are insects in the order Hymenoptera, along with ants and bees. The public may hold fears against wasps, due to their negative portrayal in various media, but they serve as integral components of a functional ecosystem. Even with their importance, many groups of wasps are still highly understudies. This dissertation aims to tackle this fear …


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 …


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 …


The Aquatic Microbial Environment Shapes The Gut Microbiota, Brain, And Behavior Of Larval Amphibians, Kyle Emerson Jun 2024

The Aquatic Microbial Environment Shapes The Gut Microbiota, Brain, And Behavior Of Larval Amphibians, Kyle Emerson

Electronic Theses and Dissertations

Microbial communities comprising bacteria, viruses, fungi, and protists live within and on the surfaces of animal hosts. These microbial communities exist in symbiosis with the host, and heavily influence host physiology, development, health, and fitness. Gut-dwelling microbes (i.e., gut microbiota) contribute to host neurodevelopment through a bidirectional Microbiota-Gut-Brain (MGB) axis. Evidence of the MGB axis has been primarily derived from studies that use germ-free (GF) models, which commonly display altered neurophysiology and behavior compared to conventionally raised counterparts. Almost all studies of the MGB axis have used mammalian models in a biomedical framework, leaving a knowledge gap regarding the role …


Quantifying Within-Population Variation In Mate Choice; Discrimination, Mate Sampling Rules, Multivariate Preference & Consequences For Sexual Selection, Kane David Stratman May 2024

Quantifying Within-Population Variation In Mate Choice; Discrimination, Mate Sampling Rules, Multivariate Preference & Consequences For Sexual Selection, Kane David Stratman

Theses and Dissertations

Mate choice is foundational to the evolution of elaborate, conspicuous, and often energetically costly displays. Modelling sexual selection in any mating system is a complicated task on two fronts; we typically confront variation in both i) the strategies of signalers and ii) how choosers assess and sample among them. As selection on mate choice behaviors emerges from the relationship between these sources of variation, it is essential that they be measured in detail. Population-level measures of chooser behaviors (i.e. pooling the single responses of a sample of choosers) have long dominated the literature on mate choice, leaving open the possibility …


Functional Analysis Of The Gamma-Aminobutyric Acid Type A Receptor Subunit Alpha-1 (Gabra1) Gene During Zebrafish Development., Nayeli Gabriela Reyes-Nava Jul 2023

Functional Analysis Of The Gamma-Aminobutyric Acid Type A Receptor Subunit Alpha-1 (Gabra1) Gene During Zebrafish Development., Nayeli Gabriela Reyes-Nava

Open Access Theses & Dissertations

The GABRA1 gene encodes for the alpha-1 (α1) subunit of the Gamma-Aminobutyric acid type A receptor (GABAAR), which are the primary modulators of synaptic inhibition in the central nervous system (CNS). Alpha-1 subunits are essential for maintaining the normal function of native receptors and contribute to over 60% of all GABAARs in the CNS. Remarkably, a broad spectrum of neurodevelopmental and epilepsy-associated disorders have been linked with mutations in the GABRA1 gene. However, the developmental, behavioral, and molecular mechanisms underlying GABRA1-associated epileptic disorders remain to be fully understood. Hence, the overarching goal of this dissertation is to investigate the behavioral …


Effects Of Maternal Disease History On Provisioning, Brooding, And Offspring Outcomes, Sakura Roberts May 2023

Effects Of Maternal Disease History On Provisioning, Brooding, And Offspring Outcomes, Sakura Roberts

Biological Sciences Undergraduate Honors Theses

Disease within a population has the ability to shape the development, evolution, and general performance of a species. Pathogen exposure to hosts can influence their physiology and behavioral patterns to further shape offspring immunity. Parental conditions experienced by offspring during early development can benefit survival and fitness (e.g. increasing provisioning rates), as well as help deter against similar diseases experienced by parents. By testing if parental behavior changes can better prepare offspring outcomes for disease exposure, such as disease severity or duration of infection, we can see the beneficial impacts it has on disease dynamics and host-pathogen processes. Incubation temperature, …


The Impacts Of Immune Challenges On Fish Behavior And Physiology, Teisha King Jan 2023

The Impacts Of Immune Challenges On Fish Behavior And Physiology, Teisha King

LSU Doctoral Dissertations

For species living in dominance hierarchies, social rank dictates access to resources and often contributes to reproductive success. To ensure survival, individuals constantly evaluate trade- offs between crucial biological systems, like the reproductive and immune systems, depending on their social rank and physiological state. Little is known about how social species balance interactions between immune system function, fluctuations in social status and reproductive fitness, and the performance of behaviors necessary for maintaining social status when sick, particularly in fishes, the largest and most diverse group of vertebrates. My dissertation research uses a whole animal approach to examine how physiological profiles …


Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman Dec 2022

Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman

Electronic Theses and Dissertations

The southern Appalachian Mountains have among the highest salamander diversity in the world, largely due to local speciation in the family Plethodontidae. Plethodontid salamanders (i.e., lungless salamanders) are particularly sensitive to habitat climate conditions due to their reliance on cutaneous respiration, and their immediate environmental conditions (microhabitat) likely influence their dispersion and activity more than the large-scale atmospheric conditions. The Northern Gray-cheeked salamander (Plethodon montanus) is restricted to high elevations in the Appalachian Mountains. Our goal was to investigate the relationship between P. montanus and its microhabitat by examining behavioral preference for climatic conditions, characterizing the microclimate with …


Bobcat Identification, Abundance, And Behavior At Road Mitigation Structures In South Texas, Victoria Hanley Dec 2022

Bobcat Identification, Abundance, And Behavior At Road Mitigation Structures In South Texas, Victoria Hanley

Theses and Dissertations

Highways in South Texas fragment the landscape and result in high road mortality rates for the endangered US ocelot (Leopardus pardalis). In response, the Texas Department of Transportation constructed nine wildlife crossing structures (WCS) on Farm-to-Market (FM) 106 which adjoins Laguna Atascosa National Wildlife Refuge in Cameron County, Texas. With ocelots being rare and elusive, bobcats (Lynx rufus) are often used as a surrogate species to study felid behavior at road mitigation structures in South Texas. Bobcats have unique markings which allow them to be individually identified. Three methods of individual identification of bobcats using camera …


Brainless But Smart: Investigating Cognitive-Like Behaviors In The Acellular Slime Mold Physarum Polycephalum, Subash Kusum Ray Aug 2022

Brainless But Smart: Investigating Cognitive-Like Behaviors In The Acellular Slime Mold Physarum Polycephalum, Subash Kusum Ray

Dissertations

Evolutionary pressures to improve fitness, have enabled living systems to make adaptive decisions when faced with heterogeneous and changing environmental and physiological conditions. This dissertation investigated the mechanisms of how environmental and physiological factors affect the behaviors of non-neuronal organisms. The acellular slime mold Physarum polycephalum was used as the model organism, which is a macroscopic, unicellular organism, that self-organizes into a network of intersecting tubules. Without using neurons, P. polycephalum can solve labyrinth mazes, build efficient tubule networks, and make adaptive decisions when faced with complicated trade-offs, such as between food quality and risk, speed and accuracy, and exploration …


Abundance, Site-Fidelity, And Association Patterns Of Coastal Bottlenose Dolphins (Tursiops Truncatus) Off Southeast Florida, Graysen D. Boehning Jul 2022

Abundance, Site-Fidelity, And Association Patterns Of Coastal Bottlenose Dolphins (Tursiops Truncatus) Off Southeast Florida, Graysen D. Boehning

All HCAS Student Capstones, Theses, and Dissertations

The coastal bottlenose dolphin is well studied throughout its natural range, however, most of the study areas comprised wide, well-protected habitats such as bays and estuaries, and not narrow coastal sandbanks. This study identifies a residential group of coastal bottlenose dolphins utilizing the narrow sandbanks within the Northwestern Atlantic waters off the coast of Palm Beach County, Florida, USA. From 2014-2020, 313 boat surveys were conducted, and 585 individual dolphins were identified using photo-ID. Twenty-four animals were determined to be full-time and 66 animals were determined to be part-time residents. Full-time and part-time residents associated in three social tribes, with …


Sodium Mediates Developmentally Plastic Responses In Plants And Herbivores, Luis Santiago-Rosario May 2022

Sodium Mediates Developmentally Plastic Responses In Plants And Herbivores, Luis Santiago-Rosario

LSU Doctoral Dissertations

Sodium plays a crucial role in organismal performance, trophic-level interactions, and eco-evolutionary dynamics. For plants, sodium impacts osmoregulation, growth, and water uptake. For animals, sodium is essential influencing osmoregulatory processes, muscle and neural development, and blood regulation. My dissertation aims to disentangle why sodium mismatch affects resource-consumer interactions and its influence on morphological and behavioral plasticity. First, I identified how sodium impacts plant performance and sodium accumulation strategies. I initially focused my research on understanding how increasing substrate sodium affects plant growth and tissue sodium accumulation strategies in controlled settings using a systematic review approach. I found that saltier plants …


The Consequences Of Climate Change For Native Bee Assemblages, Melanie R. Kazenel Apr 2022

The Consequences Of Climate Change For Native Bee Assemblages, Melanie R. Kazenel

Biology ETDs

Recent declines in terrestrial arthropod biodiversity highlight the need to pinpoint which taxa and ecosystem services are most threatened, and why. But, for most of the world’s ~20,000 bee species, we lack robust evidence of population trends, and the role of climate change remains surprisingly little studied. I used long-term bee monitoring data from the Sevilleta Long-Term Ecological Research Program (Socorro, NM, USA), along with complementary experimental and observational data, to examine how climate relates to bee abundance and diversity patterns over time and space, and to identify the traits that govern bees’ climate sensitivities.


Activity Patterns Of The Del Norte Salamander (Plethodon Elongatus): Monitoring Plethodontid Behavior Using Pit Tag Surveys, Sabrina Horrack Jan 2022

Activity Patterns Of The Del Norte Salamander (Plethodon Elongatus): Monitoring Plethodontid Behavior Using Pit Tag Surveys, Sabrina Horrack

Cal Poly Humboldt theses and projects

Semi-fossorial plethodontid salamanders exhibit behavioral plasticity to avoid desiccation, retreating underground to shelter from adverse conditions such as low precipitation and high temperatures. In this study, I used passive integrated transponder (PIT) tag surveys to monitor this behavior in the Del Norte salamander (Plethodon elongatus), a small plethodontid native to northwestern California and southwestern Oregon. Within its range, a climatic gradient exists in which coastal areas experience milder temperatures and high precipitation, while inland areas tend to have colder winters, hotter summers, and lower precipitation. By monitoring the activity patterns of this species in inland and coastal areas, …


Effects Of Exogenous Ketone Therapy On Performance, Cardiorespiration, And Seizure Genesis During Exposure To Hbo2 In The Sprague Dawley Rat, Nicole M. Stavitzski Nov 2021

Effects Of Exogenous Ketone Therapy On Performance, Cardiorespiration, And Seizure Genesis During Exposure To Hbo2 In The Sprague Dawley Rat, Nicole M. Stavitzski

USF Tampa Graduate Theses and Dissertations

Hyperbaric oxygen (HBO2) is used for clinical HBO2 therapy and in undersea and aerospace medicine. HBO2 is a humanmade extreme environment and protracted exposures can cause several adverse physiological effects on the body. For example, HBO2 increases the partial pressure of oxygen (PO2) in the body leading to redox stress. Redox stress is, in part, a cause of oxygen toxicity that manifests as seizures in its most severe form (central nervous system oxygen toxicity, CNS-OT). This dissertation focuses on strategies to be employed specifically for the warfighter breathing HBO2. Currently, the only way to prevent CNS-OT is to lower the …


Ecological Correlates Of Alligator Snapping Turtle Bite Performance, Ashley Herrin Gagnon Aug 2021

Ecological Correlates Of Alligator Snapping Turtle Bite Performance, Ashley Herrin Gagnon

MSU Graduate Theses

The Alligator Snapping Turtle (Macrochelys temminckii) is one of many turtle species facing conservation challenges. Nearly extirpated in the 1980s, it is currently the subject of a head-start initiative, of which, any lasting behavioral or physiological effects were—until now—unknown! To evaluate the ability of captive-reared individuals to excel in natural habitats, and to foresee any future research or conservation challenges regarding this animal, I explored a suite of variables that influence bite performance and behaviors including captive or free-ranging status, and environmental conditions including body temperature and season. My results indicated that free-ranging M. temminckii outperform those residing …


On The Rocks: Changes In Substrate Alter Antipredator Behavior In Benthic Stream Fish, Sarah White May 2021

On The Rocks: Changes In Substrate Alter Antipredator Behavior In Benthic Stream Fish, Sarah White

MSU Graduate Theses

Natural selection should strongly favor characteristics that make prey difficult for predators to distinguish from the background, including both morphological and behavioral crypsis. The Rainbow Darter (Etheostoma caeruleum) is a small, cryptic, benthic fish that inhabits gravel-bottomed streams and is preyed upon by predators such as the benthic Knobfin Sculpin (Cottus immaculatus) and the pelagic Longear Sunfish (Lepomis megalotis). In three experiments, I tested whether the behavior of darters was influenced by the opportunity for crypticity offered by their substrate and by the presence of cues from benthic and pelagic predators. First, darters in …


Effects Of Anthropogenic Light And Noise On Anuran Breeding Behavior, Ashley Kobisk May 2021

Effects Of Anthropogenic Light And Noise On Anuran Breeding Behavior, Ashley Kobisk

Electronic Theses and Dissertations

The natural environment can be negatively impacted by a variety of human activities, including the production of artificial light at night and anthropogenic noise. Recent studies suggest that pollution from anthropogenic light and noise alters animal behavior. Despite being highly nocturnal and vocal animals, little attention has been given to anurans and the effects artificial light at night and anthropogenic noise have on their behavior. This study investigated the effects of artificial light at night and anthropogenic noise on anuran breeding systems in eastern Texas. Specifically, this study investigated whether (1) artificial light and anthropogenic noise altered calling behavior in …


Interactive Effects Of Heat Stress And Pesticides Co-Exposure On Swimming Behavior, Oxidative Stress, Antioxidant Expression, And Redox Status In Common Goldfish (Carassius Auratus), Brittney Danielle Lacy Dec 2020

Interactive Effects Of Heat Stress And Pesticides Co-Exposure On Swimming Behavior, Oxidative Stress, Antioxidant Expression, And Redox Status In Common Goldfish (Carassius Auratus), Brittney Danielle Lacy

Theses and Dissertations

Aquatic ecosystems are inundated by environmental pesticides. This study, observed the dose-dependent effects of pesticides cocktail (metalachlor, linuron, isoproturon, tebucanazole, aclonifen, atrazine, pendimethalin, and azinphos-methyl) and elevated temperature (32 °C for 4-week exposure) on morphology of gills and kidneys, and expression of nitrotyrosine protein (NTP), dinitrophenyl protein (DNP), catalase (CAT), superoxidase dismutase (SOD), Na+/K+-ATPase, renin, and apoptosis in tissues of goldfish. Additionally, the effects on the free-swimming behavior were also observed. Histological analysis showed wide-spread damage in tissues at higher temperature and pesticides co-exposure. Immunohistochemical analysis demonstrated alterations in NTP, DNP, CAT and SOD expressions in tissues at higher temperature …


To Feed Or Not To Feed: Examining The Effects Of Provisioning Tourism On Nurse Sharks In Caye Caulker, Belize, Carlee Jackson Aug 2020

To Feed Or Not To Feed: Examining The Effects Of Provisioning Tourism On Nurse Sharks In Caye Caulker, Belize, Carlee Jackson

All HCAS Student Capstones, Theses, and Dissertations

Wildlife tourism is increasing in popularity around the world, creating the need to understand alterations in animal behavior and spatial distributions that may occur due to associated anthropogenic disturbances. Nurse sharks (Ginglymostoma cirratum, Bonnaterre 1788) are commonly used for wildlife tourism within the Caye Caulker Marine Reserve in Belize. Shark and Ray Village (SRV) is a site within the reserve where nurse sharks are consistently fed by tour/snorkel boats to create an interactive experience with tourists, termed provisioning tourism. Prior to this experiment, no studies had been conducted in SRV to evaluate the impact of provisioning tourism (tourism …


Physiological And Behavioral Correlates Of Hif-1 Alpha Protein Levels In The Gulf Killifish, Fundulus Grandis, Jasmine Harris May 2020

Physiological And Behavioral Correlates Of Hif-1 Alpha Protein Levels In The Gulf Killifish, Fundulus Grandis, Jasmine Harris

University of New Orleans Theses and Dissertations

Although the hypoxia-inducible transcription factor (HIF) orchestrates molecular responses to low oxygen, the amount of HIF-1α protein expressed during hypoxia varies among species, individuals, and tissues. This study measured HIF-1α protein levels along with several physiological and behavioral variables in the estuarine fish Fundulus grandis under normoxia (> 7 mg l-1 dissolved oxygen) and hypoxia (1 mg l-1 dissolved oxygen). Fish under hypoxic conditions had higher tissue levels of HIF-1α, hematocrit, blood glucose, blood lactate, frequency of aquatic surface respiration (ASR), and lower activity than normoxic controls. Under hypoxia, HIF-1α abundance in gill was positively correlated with body …


Investigating The Nightime Departures Of Glaucous-Winged Gulls (Larus Glaucescens) And The Role Of Social Facilitation, Devon Leigh Mcclain Jan 2020

Investigating The Nightime Departures Of Glaucous-Winged Gulls (Larus Glaucescens) And The Role Of Social Facilitation, Devon Leigh Mcclain

Master's Theses

Daytime behaviors and occupancy patterns of Glaucous-winged Gulls (Larus glaucescens) have been described and can be mathematically predicted based on environmental factors. However, little is known about the nighttime behaviors of Glaucous-winged Gulls. I used trail cameras to study the daytime and nighttime colony occupancy patterns of Glaucous-winged Gulls on a breeding colony on Protection Island, Washington, USA. Early in the breeding season gulls desert the colony en masse during nighttime even after some gulls have initiated clutches. Using acoustic recording units to identify an acoustic cue that signals the onset of the coordinated nightly departures from the colony, I …


An Ecomorphological Analysis Of Locomotion In Larvae And Neotenes Of Two Salamander Species: Dicamptodon Tenebrosus (Stream-Type) And Ambystoma Gracile (Pond-Type), Ethan Hardister Snee Jan 2020

An Ecomorphological Analysis Of Locomotion In Larvae And Neotenes Of Two Salamander Species: Dicamptodon Tenebrosus (Stream-Type) And Ambystoma Gracile (Pond-Type), Ethan Hardister Snee

Cal Poly Humboldt theses and projects

Morphology is the physical expression of a species’ evolutionary history and adaptation to its environment and as such is tied to ecology. Salamander larvae have historically been separated into "pond-type" and "stream-type" groups based on their morphology, however no studies have been performed quantifying the relationship between morphology and ecology. In this study I utilized in-situ behavioral observations, morphological measurements, and in-lab performance tests of Dicamptodon tenebrosus (stream-type) and Ambystoma gracile (pond-type) to examine the relationship between salamander larval morphology and ecology. In the field, behavior was video recorded during nighttime surveys; afterwards animals were captured and limb measurements were …


Region-Specific Modifications Of Synaptic Proteins In Response To Early-Life Adversity In The Rat Brain, Jameel Nasser Hamdan Jan 2020

Region-Specific Modifications Of Synaptic Proteins In Response To Early-Life Adversity In The Rat Brain, Jameel Nasser Hamdan

Open Access Theses & Dissertations

Drug addiction is a serious condition affecting approximately 19.7 million people in the United States alone (SAMHSA 2018). Exposure to stress and other adverse conditions has been shown to impact drug-taking behavior and making individuals more vulnerable to addiction. In those already suffering from addiction, abstaining from drug use often gives way to relapse after a stressful event (Lu, Shepard et al. 2003; Shaham, Erb et al. 2000). The experience of adversity during early-life can cause long-lasting changes in the brain, affecting development, behavior, learning and memory, and critical thinking processes, which may persist into adulthood (Aisa, Tordera et al. …


Group Differences In Mother-Infant Macaca Fascicularis Behavior, Parasite Load, And Body Condition Within An Anthropogenically Altered Forest, Elizabeth M.C. Coggeshall Jan 2020

Group Differences In Mother-Infant Macaca Fascicularis Behavior, Parasite Load, And Body Condition Within An Anthropogenically Altered Forest, Elizabeth M.C. Coggeshall

All Master's Theses

This study aimed to establish preliminary health and behavioral data, as well as understand group variation for a large population of Macaca fascicularis individuals within an anthropogenically altered monkey forest. A parasitic analysis of 40 mother and infant individuals showed that M. fascicularis carried 13 different parasitic taxa, and that there was parasitic variation between groups. Body condition scores were determined using a newly created and adapted body condition scale from 146 sampled mother macaques. Body condition scores were significantly different between groups, specifically the pond group when compared to the three other groups. Mother-infant behavioral differences were seen between …


Songbird Use Of Problem-Solving Feeders In Urban And Rural Areas, Kayce Miller Nov 2019

Songbird Use Of Problem-Solving Feeders In Urban And Rural Areas, Kayce Miller

College of Science and Health Theses and Dissertations

Behavioral flexibility is important for animals to adapt to novel situations in their environment. It has been suggested that birds living in complex environments (e.g., urban areas) should be more flexible than conspecifics in less complex environments. Birds are a particularly well studied group, where novel foraging problems are used to assess flexibility and problem-solving performance of urban and rural animals of the same species; however, this is most frequently done in a lab setting with wild-caught birds originating from different habitats. Using a field-based method to test problem-solving performance should give additional insight into other factors influencing birds’ flexibility. …


The Functional, Ecological, And Evolutionary Morphology Of Sea Lampreys (Petromyzon Marinus), Bradley Morgan Wood Nov 2019

The Functional, Ecological, And Evolutionary Morphology Of Sea Lampreys (Petromyzon Marinus), Bradley Morgan Wood

LSU Doctoral Dissertations

Lampreys (Petromyzontiformes) are jawless vertebrates with an evolutionary history lasting at least 360 million years and are often used in comparisons with jawed vertebrates because some of their morphological aspects, such as the segmented trunk musculature with curved myosepta and a non-mineralized skeleton fibrous skeleton, are thought to resemble the condition of early vertebrates before the evolution of jaws. Although earlier authors studied the morphology of the skeleto-muscular system of the trunk of lampreys, their studies are not detailed and complete enough to allow a functional and biomechanical analysis that is needed as a basis for modeling the mechanics of …


Comparative Brain Anatomy Of Lamniform Sharks (Elasmobranchii: Lamniformes) And Its Implications To Function, Behavioral Ecology, And Evolution, Francesco Guzzo Aug 2019

Comparative Brain Anatomy Of Lamniform Sharks (Elasmobranchii: Lamniformes) And Its Implications To Function, Behavioral Ecology, And Evolution, Francesco Guzzo

College of Science and Health Theses and Dissertations

Understanding the diversity of brain morphology is important to understand the evolution of cognitive ability and how ecology and phylogeny have influenced the variation in brain complexity. I examined the morphological variation of the brain in the shark order Lamniformes based on museum specimens and literature. Where I illustrate a wide range of morphological diversity in lamniform brains, my study shows that there is a strong positive correlation between brain size and body size that sharks with a larger brain tend to have a more foliated cerebellum, but that the body weight over brain weight did not correlate with cerebellar …


Neural Development To Neurodegeneration Through The Mind Of A Worm, Miranda Arnold Jun 2019

Neural Development To Neurodegeneration Through The Mind Of A Worm, Miranda Arnold

Master of Science in Integrative Biology Theses

Defects in the nervous system can impact the normal function of an organism. By examining mutations during neuronal development, we can better understand the significance of specific pathways. The EphR/ephrin pathway is crucial for axonal guidance during development. The simple organism, C. elegans, allow us to study the impact of EphR/ephrin genes on neuronal morphology, synapse connections, and basic behavior. In specific EphR/ephrin mutants, we see change in morphology and loss of synapses in a thermosensory and also a chemosensory circuit. These mutations can also lead to defects in food searching behaviors. These observations lead us to conclude that …