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Full-Text Articles in Life Sciences

Population Physiology, Demography, And Genetics Of Side-Blotched Lizards (Uta Stansburiana) Residing In Urban And Natural Environments, Spencer B. Hudson Aug 2023

Population Physiology, Demography, And Genetics Of Side-Blotched Lizards (Uta Stansburiana) Residing In Urban And Natural Environments, Spencer B. Hudson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wildlife populations across the globe are poised to lose their natural habitat to urbanization, yet there is limited information on how different species handle living in cities. Animals in urban environments are often susceptible to novel stressors, which can threaten their individual health and population viability. The physiological characteristics of animals, such as those related to metabolic hormones, oxidative stress, and immunity, are expected to be important for survival in this context. If so, animals persisting in urban areas may demonstrate physiological differences from their natural counterparts, perhaps due to evolutionary change. These potential outcomes have been documented in birds …


Competition And Herbivory Influence The Survival, Growth, And Physiology Of Native Tree Seedlings In The Kentucky Inner Bluegrass Savanna-Woodland, James D. Shaffer Jan 2023

Competition And Herbivory Influence The Survival, Growth, And Physiology Of Native Tree Seedlings In The Kentucky Inner Bluegrass Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Terrestrial plant communities are shaped by competition for resources, herbivory, and abiotic processes. Savanna systems represent a dynamic coexistence of contrasting life forms (grasses and trees) shaped by competition and disturbance. The Kentucky Inner Bluegrass Savanna-Woodland (KIBSW) is described as an open woodland of shade intolerant species; however, climatic, and edaphic conditions can support closed-canopy forest. After European pioneer settlement (c1750-1800), over 99% of “savanna-woodlands” have been lost. KIBSW remnants are experiencing a recruitment failure, leading to a dominance shift in tree communities. I researched how tree-grass competition and mammalian herbivory influence KIBSW regeneration and maintenance. The KIBSW does not …


Survival In Common Snapping Turtles, Chelydra Serpentina (Testudines: Chelydridae), In Western Nebraska, John B. Iverson, Geoffrey R. Smith Jan 2023

Survival In Common Snapping Turtles, Chelydra Serpentina (Testudines: Chelydridae), In Western Nebraska, John B. Iverson, Geoffrey R. Smith

Faculty Publications

Annual estimates of survival for Common Snapping Turtles (Chelydra serpentina) in western Nebraska USA were generated from mark-recapture data from nesting females encountered in 2005–2017. Our population models suggested no annual variation in either adult annual survival (0.947 ± 0.017 SE) or annual capture probability (0.294 ± 0.027 SE). However, there was a tendency toward higher survival in larger females. High annual survival (e.g. > 90%) characterises populations of Chelydra from Ontario to Texas.


The Effects Of Diatom-Specific Polyunsaturated Aldehydes On Larval Zebrafish (Danio Rerio), Rachel Raymer Jan 2023

The Effects Of Diatom-Specific Polyunsaturated Aldehydes On Larval Zebrafish (Danio Rerio), Rachel Raymer

WWU Graduate School Collection

Diatoms are ubiquitous in marine planktonic and benthic environments and are common in diets for many lower-trophic organisms. Certain species of diatoms produce polyunsaturated aldehydes (PUAs) that can exist in particulate and dissolved forms. Diatom PUAs are known for negatively affecting the fecundity of their primary consumers, including invertebrate grazers like copepods and echinoderms. However, little is known about the effects of diatom PUAs on vertebrates that may be exposed to dissolved or ingested PUAs due to overlapping distribution with diatom populations. The purpose of this study was to test whether dissolved diatom PUAs affect the early life stages of …


The Effect Of Polyunsaturated Aldehydes On Zebrafish Larvae Heart Rate And Mortality, Soraya Jessa Apr 2022

The Effect Of Polyunsaturated Aldehydes On Zebrafish Larvae Heart Rate And Mortality, Soraya Jessa

WWU Honors College Senior Projects

This research provides insight on the effects that polyunsaturated aldehydes (PUAs) have on model species zebrafish heart rate and mortality. Zebrafish were used as an analog for forage fish, which are of both ecological and economic importance. Forage fish often interact with diatoms, some species of which have been known to emit allelopathic chemicals, PUAs. These chemicals can have a deleterious effect on invertebrates that cohabitate with or consume diatoms, but their effects on vertebrates was unknown. In the lab, zebrafish eggs were exposed to three different concentrations of PUAs plus two controls and observed to determine any effects on …


Corbicula Fluminea Effects On Survival, Growth, And Drift Of Juvenile Lampsilis Siliquoidea In Laboratory Exposures, Allison Nicole Sieja Aug 2021

Corbicula Fluminea Effects On Survival, Growth, And Drift Of Juvenile Lampsilis Siliquoidea In Laboratory Exposures, Allison Nicole Sieja

MSU Graduate Theses

The Asian clam, Corbicula fluminea, is an invasive species that is abundant and often co-occurs with native freshwater mussels. Corbicula is widely suspected of having negative effects on native mussels, but few studies have empirically tested this hypothesis. I used laboratory experiments to evaluate how adult Corbicula affected the survivorship, growth, and drift of juvenile Lampsilis siliquoidea. Survival and growth of newly metamorphosed mussels were tested in downwelling flow-through chambers with glass-bead substrate. Treatments were control (no clams), small adult clams, or large adult clams. After 28 days, large clams slightly but significantly reduced the number of juveniles …


A Reintroduction Retrospective: Comparative Fisher (Pekania Pennanti) Survival And Prey Habitat Use In The Cascade Mountains Of Washington State, Tanner S.T. Humphries Jan 2021

A Reintroduction Retrospective: Comparative Fisher (Pekania Pennanti) Survival And Prey Habitat Use In The Cascade Mountains Of Washington State, Tanner S.T. Humphries

Graduate Student Theses, Dissertations, & Professional Papers

Increasing human impacts on biodiversity highlight the global need for ecological restoration. For many wildlife species, reintroduction is necessary to re-establish populations in parts of their historic range where they have been extirpated. Reintroduction efforts are commonly used to help restore ecosystem integrity, but are often expensive, time consuming, and unsuccessful at generating self-sustaining populations. Thus, a more complete understanding of the factors affecting restoration success is important for ensuring successful outcomes and responsible stewardship. Fishers (Pekania pennanti) are one of the most commonly reintroduced carnivores in North America, but the success of such efforts is highly variable, …


Identification Of Predation Events In Wild Fish Using Novel Acoustic Transmitters, Amy A. Weinz, Jordan K. Matley, Natalie V. Klinard, Aaron T. Fisk, Scott F. Colborne Aug 2020

Identification Of Predation Events In Wild Fish Using Novel Acoustic Transmitters, Amy A. Weinz, Jordan K. Matley, Natalie V. Klinard, Aaron T. Fisk, Scott F. Colborne

Great Lakes Institute for Environmental Research Publications

Background: Acoustic telemetry is a commonly used tool to gain knowledge about aquatic animal ecology through the study of their movements. In telemetry studies researchers must make inferences regarding the movements and the fates of tagged animals. Until recently, predation has been inferred in telemetry data using a variety of methods including abrupt changes in movement patterns or habitat use. An acoustic telemetry transmitter has been developed to detect predation events of tagged animals, and while they have performed well in controlled laboratory trials, literature regarding the application of these novel transmitters in field settings is limited. The objective of …


Juvenile Rank Acquisition Is Associated With Fitness Independent Of Adult Rank, Eli D. Strauss, Daizaburo Shizuka, Kay E. Holekamp Feb 2020

Juvenile Rank Acquisition Is Associated With Fitness Independent Of Adult Rank, Eli D. Strauss, Daizaburo Shizuka, Kay E. Holekamp

School of Biological Sciences: Faculty Publications

Social rank is a significant determinant of fitness in a variety of species. The importance of social rank suggests that the process by which juveniles come to establish their position in the social hierarchy is a critical component of development. Here, we use the highly predictable process of rank acquisition in spotted hyenas to study the consequences of variation in rank acquisition in early life. In spotted hyenas, rank is ‘inherited’ through a learning process called ‘maternal rank inheritance.’ This pattern is very consistent: approximately 80% of juveniles acquire the exact rank expected under the rules of maternal rank inheritance. …


The Birds And The Trees, Branden Lawson Jan 2020

The Birds And The Trees, Branden Lawson

McNair Scholars

Modification of natural habitats used by native organisms is occurring more rapidly due to the increasing human population. American Robins (Turdus migratorius) are common in urban and non-urban areas and can serve as useful indicators of human activities' effects on wildlife. To create an urban environment, the removal of trees from non-urban habitats is necessary but causes radical alteration of the presence of native avifauna. This study, therefore, examined the influence of tree cover within urban and non-urban sites and how trees' characteristics affected the survival rate of American Robin chicks. Data collection occurred during the 2019 breeding …


Dispersal And Survival Of Red-Shouldered Hawks Banded In Suburban Southern Ohio, 1996-2018, Cheryl R. Dykstra, Jeffrey L. Hays, Melinda M. Simon, Ann R. Wegman, Laura R. Dykstra Sep 2019

Dispersal And Survival Of Red-Shouldered Hawks Banded In Suburban Southern Ohio, 1996-2018, Cheryl R. Dykstra, Jeffrey L. Hays, Melinda M. Simon, Ann R. Wegman, Laura R. Dykstra

University Faculty Publications and Creative Works

We used banding data to investigate dispersal and survival of Red-shouldered Hawks (Buteo lineatus) in two study areas in southern Ohio from 1996 to 2018. Of the 2448 nestlings we banded, 167 (6.8%) were encountered (dead or alive) some time after banding. Mean distance from the natal nest at the time of encounter was 31.6 ± 6.2 km (median = 10.0, range = 0.1-568.6 km, n = 163); natal dispersal distance averaged 16.0 ± 1.9 km (median = 9.0, range = 1.4-117.1 km, n = 110), and was significantly greater for females than for males. Most hawks dispersedkm, but 11 …


Demographic Assessment Of The Triploid Parthenogenetic Lizard Aspidoscelis Neotesselatus At The Northern Edge Of Its Range, Lise M. Aubry, Douglas Eifler, Kaera Utsumi, Susannah S. French Aug 2019

Demographic Assessment Of The Triploid Parthenogenetic Lizard Aspidoscelis Neotesselatus At The Northern Edge Of Its Range, Lise M. Aubry, Douglas Eifler, Kaera Utsumi, Susannah S. French

Biology Faculty Publications

Aspidoscelis neotesselatus (Colorado Checkered Whiptail) is a hybrid-derived triploid parthenogenetic lizard with a natural range overlapping with six counties in southeastern Colorado, USA. It has also become established by anthropogenic causation in Grant County, Washington State, approximately 1,600 km northwest of its range in Colorado. Large parts of its natural range are within military reservations. Reduced genetic variation in all-female species makes them especially susceptible to environmental disturbances, such as military activities. At Fort Carson (FC), we estimated an abundance index via a catch-per-unit estimator, weekly survival using Cormack-Jolly-Seber models, and body condition and clutch size as indicators of population …


The Incorporation Of Lipids Into The Cellular Membrane Of Salmonella, Betsy H. Redfern May 2019

The Incorporation Of Lipids Into The Cellular Membrane Of Salmonella, Betsy H. Redfern

Honors Theses

Salmonella is a gram negative, facultative anaerobic food borne pathogen and is the leading cause of deaths related to food borne illnesses. In order to establish an infection successfully, Salmonella must be able to survive in the presence of various stressors that it encounters, namely changes in pH, oxygen availability, osmolarity and bile. Previous research has shown that exposure to bile causes a shift in fatty acid composition in the cell membrane of the enteric bacterium Enterococcus faecalis. Thus, this led to the hypothesis that Salmonella incorporates fatty acids into its cellular membrane following exposure to bile and thereby protects …


Life‐History Differences Across Latitude In Common Side‐Blotched Lizards (Uta Stansburiana), Geoffrey D. Smith, Peter A. Zani, Susannah S. French Apr 2019

Life‐History Differences Across Latitude In Common Side‐Blotched Lizards (Uta Stansburiana), Geoffrey D. Smith, Peter A. Zani, Susannah S. French

Biology Faculty Publications

  1. Life‐history strategies are known to shift with latitude in many species. While life‐history variation related to body size, reproductive investment, and behavior has been studied for years, another crucial life‐history component is the immune system, which can influence an animal's survival.
  2. We measured selected life‐history traits in side‐blotched lizards in southern Utah and Oregon in the field for two consecutive years and conducted a common‐garden experiment in the laboratory to determine how organisms from different latitudes optimize either immunity or reproduction. We observed lizards from southern populations, which are known to be shorter‐lived, had lower immune function during reproduction when …


Population Dynamics And Demographics Of Spotted Seatrout, Cynoscion Nebulosus, Through Spatial Analysis: Towards An Integrative Management Approach, Ashley Melancon Baer Mar 2019

Population Dynamics And Demographics Of Spotted Seatrout, Cynoscion Nebulosus, Through Spatial Analysis: Towards An Integrative Management Approach, Ashley Melancon Baer

LSU Doctoral Dissertations

Spotted seatrout (Cynoscion nebulosus) is one of the most highly prized sportfish along the Gulf of Mexico coast, particularly in Louisiana. Although spotted seatrout are considered to be well managed and sustainably fished according to the state’s most recent stock assessment, the spatial ecology of this species is largely understudied in Louisiana waters. Acoustic telemetry is an innovative technology that is commonly used to assess the movements and behavior of aquatic species, and can be used as a tool to address the paucity of information on the spatial dynamics of spotted seatrout. The focus of this study was …


Postfledging Habitat Selection And Survival Of Henslow’S Sparrow: Management Implications For A Critical Life Stage, Aaron C. Young, W. Andrew Cox, John P. Mccarty, L. Lareesa Wolfenbarger Jan 2019

Postfledging Habitat Selection And Survival Of Henslow’S Sparrow: Management Implications For A Critical Life Stage, Aaron C. Young, W. Andrew Cox, John P. Mccarty, L. Lareesa Wolfenbarger

Biology Faculty Publications

Conserving populations of species that rely on rare habitat requires that managers understand which habitat characteristics will best support population growth across multiple life stages. For songbirds, management is most often aimed at nesting adult habitat associations. However, habitat that meets adult requirements may not be similarly suited to requirements for other life stages. Henslow’s Sparrow (Centronyx henslowii) is a tallgrass prairie songbird listed as threatened or endangered in 13 states. We examined survival and habitat selection of Henslow’s Sparrow during the postfledging period. During the nesting seasons in 2015 and 2016, we attached radio transmitters to 46 nestlings in …


Canis Lupus (Gray Wolf) Pup Survival In Yellowstone National Park, Anne Marie Jehle Jan 2019

Canis Lupus (Gray Wolf) Pup Survival In Yellowstone National Park, Anne Marie Jehle

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The aim of this study was to describe gray wolf (Canis lupus) pup survival rates throughout the summer months in Yellowstone National Park. Understanding pup survival has implications for trends in pack and population age structure, cooperative breeding ecology and other breeding tendencies, social hierarchies, and population fitness, among other elements of species-specific population ecology. A general understanding of trends in pup survival is also relevant to state and federal land that allow gray wolf harvest. Understanding such trends and survival ecology gives managers and biologists the opportunity to evaluate gray wolf populations at a more comprehensive level and implement …


Recruitment, Survival, And Parasitism Of Monarch Butterflies (Danaus Plexippus) In Milkweed Gardens And Conservation Areas, Emily A. Geest, L. Lareesa Wolfenbarger, John P. Mccarty Nov 2018

Recruitment, Survival, And Parasitism Of Monarch Butterflies (Danaus Plexippus) In Milkweed Gardens And Conservation Areas, Emily A. Geest, L. Lareesa Wolfenbarger, John P. Mccarty

Biology Faculty Publications

Monarch butterflies (Danaus plexippus) are suffering from declining populations and conservationists have encouraged planting milkweed gardens in urban and suburban landscapes to help offset habitat loss across the breeding range. The effectiveness of gardens as a conservation strategy depends on their ability to attract ovipositing adults and the survival of monarch larvae in these gardens. Larvae are susceptible to a variety of predators as well as to parasitism by a tachinid fly (Lespesia archippivora) and a protozoan parasite (Ophryocystis elektroscirrha) which cause lethal or sublethal effects, yet the severity of these risks in gardens …


The Role Of Genomic Versatility In Multi-Niche Preferences Of Escherichia Coli, Gitanjali Nandakafle Jan 2018

The Role Of Genomic Versatility In Multi-Niche Preferences Of Escherichia Coli, Gitanjali Nandakafle

Electronic Theses and Dissertations

Escherichia coli strains are naturally present as either commensals or pathogens in the gastrointestinal tract of mammals and some other vertebrates. Until recently, it was assumed that E. coli are solely associated with the gut and are unable to survive outside of a host for a long period of time, the basis of its use as an indicator organism. Recent reports suggest that E. coli can become naturalized to several tropical, subtropical or temperate soils and aquatic environments, where they have been isolated repeatedly. Several studies have shown that these strains are capable of surviving and proliferating in the environment …


Resource Selection, Survival, And Departure Of Adult Female Mallards From The Lake St. Clair Region During Autumn And Winter, Matthew Palumbo Dec 2017

Resource Selection, Survival, And Departure Of Adult Female Mallards From The Lake St. Clair Region During Autumn And Winter, Matthew Palumbo

Electronic Thesis and Dissertation Repository

During autumn and winter, mallards (Anas platyrhynchos) maximize fitness through their spatiotemporal distribution to avoid mortality risks while balancing trade-offs to access foods to undergo migration and maintain homeostasis. Thousands of mallards use Lake St. Clair as it is an important, but threatened, migratory staging area in the Great Lakes. My goal was to understand how mallards were selecting resources in the region and potential relationships of selection strategies. My objectives were to estimate resource selection of adult female mallards, in relation to perceived risk of hunting mortality, and determine if selection strategies were related to survival and …


Klf9 And Jnk3 Interact To Suppress Axon Regeneration In The Adult Cns, Akintomide Apara, Joana Galvao, Yan Wang, Murray G. Blackmore, Allison Trillo, Keiichiro Iwao, Dale P. Brown Jr., Kimberly A. Fernandes, Abigail Huang, Tu Nguyen, Masoumeh Ashouri, Ziong Zhang, Peter S. Shaw, Noelia J. Kunzevitzky, Darcie L. Moore, Richard T. Libby, Jeffrey L. Goldberg Oct 2017

Klf9 And Jnk3 Interact To Suppress Axon Regeneration In The Adult Cns, Akintomide Apara, Joana Galvao, Yan Wang, Murray G. Blackmore, Allison Trillo, Keiichiro Iwao, Dale P. Brown Jr., Kimberly A. Fernandes, Abigail Huang, Tu Nguyen, Masoumeh Ashouri, Ziong Zhang, Peter S. Shaw, Noelia J. Kunzevitzky, Darcie L. Moore, Richard T. Libby, Jeffrey L. Goldberg

Biological Sciences Faculty Research and Publications

Neurons in the adult mammalian CNS decrease in intrinsic axon growth capacity during development in concert with changes in Krüppel-like transcription factors (KLFs). KLFs regulate axon growth in CNS neurons including retinal ganglion cells (RGCs). Here, we found that knock-down of KLF9, an axon growth suppressor that is normally upregulated 250-fold in RGC development, promotes long-distance optic nerve regeneration in adult rats of both sexes. We identified a novel binding partner, MAPK10/JNK3 kinase, and found that JNK3 (c-Jun N-terminal kinase 3) is critical for KLF9's axon-growth-suppressive activity. Interfering with a JNK3-binding domain or mutating two newly discovered serine phosphorylation acceptor …


Seasonal Ecology Of Mottled Sculpin And Brown Trout In A Coldwater Michigan Stream, Susanna K. Lagory Aug 2017

Seasonal Ecology Of Mottled Sculpin And Brown Trout In A Coldwater Michigan Stream, Susanna K. Lagory

Masters Theses

In temperate regions, environmental conditions vary distinctly between seasons. This variation can strongly impact in-stream environmental conditions. Winter is often thought to be harsher than other seasons for stream fishes, given the adverse environmental conditions that arise from low temperatures during winter in temperate regions. Low temperatures, episodic elevated discharge, and ice formation associated with winter are hypothesized to reduce movement, body condition, and survival of stream fishes. However, few studies test this hypothesis through formal comparisons, and most studies of seasonal stream fish ecology focus on salmonids. To address this knowledge gap, I estimated and compared body condition, net …


Nest-Site Selection And Neonate Survival Of Eastern Box Turtles (Terrapene Carolina Carolina) In Michigan’S Northern Lower Peninsula, Joseph T. Altobelli Aug 2017

Nest-Site Selection And Neonate Survival Of Eastern Box Turtles (Terrapene Carolina Carolina) In Michigan’S Northern Lower Peninsula, Joseph T. Altobelli

Masters Theses

Turtles (Order Testudines) are experiencing global declines largely due to anthropogenic influences such as habitat fragmentation, illegal collection and sales, and the threat of global climate change. Removal of individuals from the adult age-classes means there is now a greater need to understand the survival of neonate and juvenile turtle age-classes. In this study I examined a population of eastern box turtles (Terrapene carolina carolina) at the northern limit of their range in Michigan’s lower peninsula. The objectives of my thesis were 1. to determine the microhabitat factors that influence nestsite selection by female box turtles and how …


Conservation Implications Of A Lack Of Relationship Between Baseline Glucocorticoids And Fitness In A Wild Passerine, Christine L. Madliger, Oliver P. Love Dec 2016

Conservation Implications Of A Lack Of Relationship Between Baseline Glucocorticoids And Fitness In A Wild Passerine, Christine L. Madliger, Oliver P. Love

Integrative Biology Publications

The application of physiological measures to conservation monitoring has been gaining momentum and, while a suite of physiological traits are available to ascertain disturbance and condition in wildlife populations, glucocorticoids (i.e., GCs; cortisol and corticosterone) are the most heavily employed. The interpretation of GC levels as sensitive indicators of population change necessitates that GCs and metrics of population persistence are linked. However, the relationship between GCs and fitness may be highly context-dependent, changing direction, or significance, depending on the GC measure, fitness metric, life history stage, or other intrinsic and extrinsic contexts considered. We examined the relationship between baseline plasma …


Detritus Quality And Locality Determines Survival And Mass, But Not Export, Of Wood Frogs At Metamorphosis, Joseph R. Milanovich, Kyle Barrett, John A. Crawford Nov 2016

Detritus Quality And Locality Determines Survival And Mass, But Not Export, Of Wood Frogs At Metamorphosis, Joseph R. Milanovich, Kyle Barrett, John A. Crawford

Faculty Scholarship

Single-site experiments have demonstrated detritus quality in wetlands can have strongly negative, neutral, and even positive influences on wildlife. However, an examination of the influence of detritus quality across several regions is lacking and can provide information on whether impacts from variation in detritus quality are consistent across species with wide ranges. To address this gap in regional studies we examined effects of emergent and allochthonous detritus of different nutrient qualities on amphibians and assessed a mechanism that may contribute to potential impacts. We used aquatic mesocosms to raise wood frogs (Rana sylvatica) from two regions of the United States …


Abiotic Factors Contributing To The Survival Of Three Tick Species In Southeastern Virginia, Amblyomma Americanum (Lone Star Tick), Dermacentor Variabilis (American Dog Tick), And Amblyomma Maculatum (Gulf Coast Tick), Lindsey A. Bidder Oct 2016

Abiotic Factors Contributing To The Survival Of Three Tick Species In Southeastern Virginia, Amblyomma Americanum (Lone Star Tick), Dermacentor Variabilis (American Dog Tick), And Amblyomma Maculatum (Gulf Coast Tick), Lindsey A. Bidder

Biological Sciences Theses & Dissertations

Amblyomma americanum, Amblyomma maculatum, and Dermacentor variabilis are hard-bodied ticks in the Hampton Roads area of southeastern Virginia. This study consisted of two field projects focused on these tick species. To estimate the off-host survival of local tick species, a capture-mark-recapture (CMR) study was performed. An environmental survival study was performed to quantify the ability of these three tick species to survive in situ. Four field sites were used in the Hampton Roads region covering a variety of habitat types and vegetation; specifically two drier, upland field sites and two flood-prone sites. CMR was conducted from May through …


The Role Of Oncogenic Kras In Initiation, Progression And Maintenance Of Pancreatic Cancer, Nirakar Rajbhandari May 2016

The Role Of Oncogenic Kras In Initiation, Progression And Maintenance Of Pancreatic Cancer, Nirakar Rajbhandari

Theses & Dissertations

Pancreatic cancer is a lethal disease that is almost invariably associated with a KRAS gene mutation. Due to a very high frequency of gain-of-function mutations within the KRAS gene, and its proven role in initiation of pancreatic cancer in animal models, mutant KRAS is considered a rational therapeutic target. To determine the potential role of oncogenic KRAS in pancreatic tumor maintenance in vivo, we generated a mouse model with a Doxycycline regulated expression of oncogenic KRAS (KRASG12D) in pancreas. Using this reversible model, we demonstrated that the expression of oncogenic KRAS in a Cdkn2a deficient background was …


Further Support For Thermal Ecosystem Engineering By Wandering Albatross On Marion Island, Steven L Chown, Justine D. Shaw, Tanya M Haupt, Brent J Sinclair Feb 2016

Further Support For Thermal Ecosystem Engineering By Wandering Albatross On Marion Island, Steven L Chown, Justine D. Shaw, Tanya M Haupt, Brent J Sinclair

Biology Publications

On sub-Antarctic Marion Island, wandering albatross (Diomedea exulans) nests support high abundances of tineid moth, Pringleophaga marioni, caterpillars. Previous work proposed that the birds serve as thermal ecosystem engineers by elevating nest temperatures relative to ambient, thereby promoting growth and survival of the caterpillars. However, only 17 days of temperature data were presented previously, despite year-long nest occupation by birds. Previous sampling was also restricted to old and recently failed nests, though nests from which chicks have recently fledged are key to understanding how the engineering effect is realized. Here we build on previous work by providing nest temperature data …


Integrated Survival Analysis Using An Event-Time Approach In A Bayesian Framework, Daniel P. Walsh, Victoria J. Dreitz, Dennis M. Heisey Jan 2015

Integrated Survival Analysis Using An Event-Time Approach In A Bayesian Framework, Daniel P. Walsh, Victoria J. Dreitz, Dennis M. Heisey

Wildlife Biology Faculty Publications

Event-time or continuous-time statistical approaches have been applied throughout the bio-statistical literature and have led to numerous scientific advances. However, these techniques have traditionally relied on knowing failure times. this has limited application of these analyses, particularly, within the ecological field where fates of marked animals may be unknown. To address these limitations, we developed in integrated approach within a Bayesian framework to estimate hazard rates in the face of unknown fates. We combine failure/survival times from individuals whose fates are known and times of which are interval-censored with information from those whose fates are unknown, and model the process …


Vital Rates And Population Demographics In Declining And Stable Watersnake Populations, John H. Roe, Omar Attum, Bruce A. Kingsbury Ph.D. Jan 2015

Vital Rates And Population Demographics In Declining And Stable Watersnake Populations, John H. Roe, Omar Attum, Bruce A. Kingsbury Ph.D.

Bruce A Kingsbury Ph.D.

many snake populations have experienced significant declines, including the copper-bellied Watersnake (nerodia erythrogaster neglecta), a species listed as threatened under the federal endangered species act. here, we assess aspects of population biology and vital rates in n. e. neglecta to help elucidate potential mechanisms of their decline and inform more targeted recovery efforts. We use the common Watersnake (nerodia sipedon sipedon) as a benchmark for comparison. survey results indicate that the n. e. neglecta population may have experienced a 70% decline in abundance from 2001– 2006, whereas the n. s. sipedon population remained relatively stable. annual survivorship rates did not …