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The Assessment Of Predictor Variables For Hard Tick Abundance In Southwestern Missouri, Casey L. Adkins May 2019

The Assessment Of Predictor Variables For Hard Tick Abundance In Southwestern Missouri, Casey L. Adkins

Graduate Theses/Dissertations

The risk of tick-borne infection is increasing across the United States, and in Missouri, ticks are expanding into novel regions due to climate change, habitat fragmentation, and biodiversity loss. Regions in which ticks are encroaching experience novel vectors for lineage associated pathogens. Novel tick detection can be low due to sampling practices targeting known ticks, which can lead to unreliable distribution maps and poor predictive distribution models. Such models should account for biotic factors, abiotic factors, and their interactions to provide a dynamic view of their impact on tick abundance and identify variables that can serve as indicators. Further, a …


Additional Thoughts On Rigor In Wildlife Science: Unappreciated Impediments, John A. Bissonette May 2019

Additional Thoughts On Rigor In Wildlife Science: Unappreciated Impediments, John A. Bissonette

Wildland Resources Faculty Publications

Traditionally, most scientists accepted reductionist and mechanistic approaches as the rigorous way to do science. Sells et al. (2018) recently raised the argument about reliability in wildlife science. Chamberlin (1890), Platt (1964), Romesburg (1981, 1991, 2009), and Williams (1997) were rightly referenced as very influential papers. My intention in this letter is not to refute the essence of the Sells et al. (2018) commentary but to add seldom addressed but important aspects that influence the attainment of rigor and certainty in wildlife studies. The elements of …


Clinical Implications Of Evolutionary Modeling Of Cancer Progression, Kelsey Heiland May 2019

Clinical Implications Of Evolutionary Modeling Of Cancer Progression, Kelsey Heiland

Biology: Student Scholarship & Creative Works

Evolutionary theory of cancer was developed in 1976 by cancer research Peter Nowell and has illuminated the path toward increasing safety and efficacy of clinical treatment strategies. Major foundations that makeup the complexity in Darwinian framework of cancer includes clonal evolution, clonal expansion, and competition. Due to these characteristics, virtually all types of cancer have evolutionary capabilities to reject or adapt and become resistant to pharmaceutical therapies. Despite compelling evidence of these process, evolutionary modeling of cancer continues to be underutilized in clinical settings. Contributions to this include the complex adaptive mechanisms that tools fail to detect or are unable …


Examining The Effect Of Interstitial Space On Eastern Oysters (Crassostrea Virginica): Applications Of Photogrammetry And Three-Dimensional Modeling, Bailie Lavan May 2019

Examining The Effect Of Interstitial Space On Eastern Oysters (Crassostrea Virginica): Applications Of Photogrammetry And Three-Dimensional Modeling, Bailie Lavan

Masters Theses, 2010-2019

Global oyster populations have decreased by as much as 99% in the past century. Oysters are known ecosystem engineers, providing benthic habitat for macrofauna, linking benthic and pelagic food webs, improving water quality, and mitigating shoreline erosion. Restoration efforts are critical in re-establishing native oyster populations. In the Chesapeake Bay, where oyster loss is primarily due to severe over harvest, artificial substrates with geometric shapes are widely used in restoration efforts. However, natural oyster reefs form emergent shapes with a high degree of aggregation and many interstitial spaces (three-dimensional volumetric spaces between oysters within a reef). The lack of interstitial …


Insect Populations Across An Urban-To-Suburban Land Use Gradient., Jacob T. Lawson May 2019

Insect Populations Across An Urban-To-Suburban Land Use Gradient., Jacob T. Lawson

College of Arts & Sciences Senior Theses

Insect populations, especially those of pollinators, have been steadily declining across the globe in recent decades, a trend that is intensified in cities. Since the conservation of pollinators is crucial for maintaining ecosystems and ecological processes, new approaches are being promoted beyond those of conserving large natural areas. Urban native plant gardens could potentially offset some of these losses locally. This research attempts to set a local baseline for the insect diversity in urban gardens in Louisville and determine whether differences exist in garden insects in cities versus suburbs in Jefferson County, Kentucky. To address the land-use question we established …


Amphibian And Reptile Community Responses To Forest And Riparian Disturbance, Jacquelyn Christine Guzy May 2019

Amphibian And Reptile Community Responses To Forest And Riparian Disturbance, Jacquelyn Christine Guzy

Graduate Theses and Dissertations

Riparian zones are transitional, semi-terrestrial areas regularly influenced by freshwater. These areas serve as dispersal corridors for many animal and plant species and ultimately function as important reservoirs of biodiversity in altered landscapes. While much of the riparian habitat in the United States has been affected by anthropogenic activities, management actions may mitigate potentially negative influences of these activities. For example, Streamside Management Zones (i.e., riparian buffers; SMZs) are commonly implemented within managed forests to protect water quality, but may also provide habitat for riparian-associated wildlife. Yet, little research has rigorously addressed the value of SMZs for wildlife, particularly cryptic …


Integration Of Genotype, Physiological Performance, And Survival In A Lizard (Uta Stansburiana) With Alternative Mating Strategies, Lisa Hazard, Kenneth A. Nagy, Donald B. Miles, Erik I. Svensson, Daniel Costa, Barry Sinervo May 2019

Integration Of Genotype, Physiological Performance, And Survival In A Lizard (Uta Stansburiana) With Alternative Mating Strategies, Lisa Hazard, Kenneth A. Nagy, Donald B. Miles, Erik I. Svensson, Daniel Costa, Barry Sinervo

Department of Biology Faculty Scholarship and Creative Works

Covariation among behavioral and physiological traits is thought to enhance reproductive success and Darwinian fitness. Species that exhibit alternative mating strategies provide excellent opportunities to assess the relative contributions of physiological and behavioral traits to fitness. Male side-blotched lizards (Uta stans-buriana) exhibit three heritable throat color morphs that are associated with alternative mating behaviors. The three morphs differ in resource holding potential, mate attraction, mate defense, and physiological performance. We examined interrelationships of body mass, stamina, field metabolic rate, growth rate, and survival to the second capture (a fitness proxy). Relationships among variables were complex, and mass, stamina, and throat …


Assessing Minimal-Input Restoration Strategies For Desert Soil And Vegetation Restoration, Audrey Jean Rader May 2019

Assessing Minimal-Input Restoration Strategies For Desert Soil And Vegetation Restoration, Audrey Jean Rader

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Mojave and Sonoran Deserts have been negatively impacted by anthropogenic disturbances. Considering that these ecosystems may recover on millennial timescales, research has shown that restoration techniques can be fairly successful in initiating long-term recovery processes in these sensitive environments. However, uncertainty remains as to which techniques are effective in different circumstances, such as in different climates or across different soil properties, and which techniques may best avoid unintended consequences, such as facilitating non-native plants. To reduce fugitive dust as a human health hazard, increase soil stability, and enhance wildlife habitat, further work is necessary to develop restoration techniques for …


Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell May 2019

Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell

Master's Theses

Global biodiversity is declining as a direct result of anthropogenic climate change. Ectothermic species have become focal organisms for studying the ecological effects of altered climates due to the clear relationship between environmental temperatures and ectotherms’ basic physiological functions. Historically, examinations of these effects have focused heavily on heliothermic lizards, and most others have tended to focus on single populations or sympatric species within a single community. Addressing the longterm energetic implications of environmental temperature variation will provide valuable insight into the cascading physiological effects that certain populations or species may experience as a result of altered climates.

In this …


Beyond Genetics: Addressing Activity In Microbial Ecology, Scott Christopher Thomas May 2019

Beyond Genetics: Addressing Activity In Microbial Ecology, Scott Christopher Thomas

UNLV Theses, Dissertations, Professional Papers, and Capstones

The field of microbial ecology is on the cusp of another revolution, one that uses synergy to address the limitations of previous studies. My dissertation is representative of the new era of research to come, through combining the latest technological advances with established classical methods to provide a more complete understanding of microbial ecosystems. In my first study, I evaluate the conservation of central carbon metabolic pathways and activity along a temperature and diversity gradient (60-95 ℃) through the use of 16S rRNA gene amplicon data, metagenome sequencing, and position-specific 13C-labeled metabolite probing. In my second study, I provide the …


What Does The Snake Eat? Breadth, Overlap, And Non-Native Prey In The Diet Of Three Sympatric Natricine Snakes, Emily E. Virgin, Richard B. King Apr 2019

What Does The Snake Eat? Breadth, Overlap, And Non-Native Prey In The Diet Of Three Sympatric Natricine Snakes, Emily E. Virgin, Richard B. King

Biology Faculty Publications

We investigated diet breadth and diet overlap in three sympatric snakes of similar body size: Dekay’s Brownsnakes (Storeria dekayi), Red-bellied Snakes (S. occipitomaculata), and sub-adult Common Gartersnakes (Thamnophis sirtalis), by examining recently consumed prey (n = 388) collected from wild-caught snakes (n = 263) in northern Illinois. Storeria occipitomaculata were dietary specialists, feeding nearly exclusively on slugs. Storeria dekayi fed predominately on slugs but also consumed snails and earthworms. Sub-adult T. sirtalis fed predominately on earthworms but also consumed frogs and small mammals. Diet overlap was extensive between Storeria species but relatively low between …


Marine Reserves Shape Seascapes On Scales Visible From Space, Elizabeth M. P. Madin, Alastair R. Harborne, Aaron M. T. Harmer, Osmar J. Luiz, Trisha Brooke Atwood, Brian J. Sullivan, Joshua S. Madin Apr 2019

Marine Reserves Shape Seascapes On Scales Visible From Space, Elizabeth M. P. Madin, Alastair R. Harborne, Aaron M. T. Harmer, Osmar J. Luiz, Trisha Brooke Atwood, Brian J. Sullivan, Joshua S. Madin

Watershed Sciences Faculty Publications

Marine reserves can effectively restore harvested populations, and ‘mega-reserves’ increasingly protect large tracts of ocean. However, no method exists of monitoring ecological responses at this large scale. Herbivory is a key mechanism structuring ecosystems, and this consumer–resource interaction's strength on coral reefs can indicate ecosystem health. We screened 1372, and measured features of 214, reefs throughout Australia's Great Barrier Reef using high-resolution satellite imagery, combined with remote underwater videography and assays on a subset, to quantify the prevalence, size and potential causes of ‘grazing halos’. Halos are known to be seascape-scale footprints of herbivory and other ecological interactions. Here we …


Comparison Of Postfire Seedling Recruitment Of 2019 In Three Key Chaparral Species, Karagan Smith, Reid Furukawa, Brett Muramoto, Stephen D. Davis Apr 2019

Comparison Of Postfire Seedling Recruitment Of 2019 In Three Key Chaparral Species, Karagan Smith, Reid Furukawa, Brett Muramoto, Stephen D. Davis

Featured Research

Fire is a common natural disaster that sweeps through Southern California. Combined with periods of acute, and most recent, chronic drought, we have seen an increase in the damage and frequency of these fires in recent years. Three chaparral species are common to the Pepperdine campus: Malosma laurina, Ceanothus spinosus, and Ceanothus megacarpus. The survival of these three native species is essential because they serve as biomarkers for the changes that are occurring in our local ecosystem and provide further implications for how our ecosystem is responding to natural disaster. Seedling recruitment is a mechanism that is used by …


Rediscovering The Axolotl As A Model For Thyroid Hormone Dependent Development, Anne Crowner, Shivam Khatri, Dana Blichmann, S. Randal Voss Apr 2019

Rediscovering The Axolotl As A Model For Thyroid Hormone Dependent Development, Anne Crowner, Shivam Khatri, Dana Blichmann, S. Randal Voss

Neuroscience Faculty Publications

The Mexican axolotl (Ambystoma mexicanum) is an important model organism in biomedical research. Much current attention is focused on the axolotl's amazing ability to regenerate tissues and whole organs after injury. However, not forgotten is the axolotl's equally amazing ability to thwart aspects of tissue maturation and retain juvenile morphology into the adult phase of life. Unlike close tiger salamander relatives that undergo a thyroid hormone regulated metamorphosis, the axolotl does not typically undergo a metamorphosis. Instead, the axolotl exhibits a paedomorphic mode of development that enables a completely aquatic life cycle. The evolution of paedomorphosis allowed axolotls …


The Physico-Chemical Environment And Aquatic Biodiversity Of Head Marala Wetland During 2000-2001, Zahid Bhatti, Muhammad Asif Gondal, Andleeb Batool Apr 2019

The Physico-Chemical Environment And Aquatic Biodiversity Of Head Marala Wetland During 2000-2001, Zahid Bhatti, Muhammad Asif Gondal, Andleeb Batool

Journal of Bioresource Management

An ecological study on Head Marala Wetland was undertaken. The study will help in providing sound basis for the future conservation activities and its management, on sounder footing. The Marala wetlands in Bajwat area included river Jammu Tawi, river Chanab and river Manawar Tawi were studied for a period of one year, i.e. from October, 2000 to September, 2001. In this study, 36 Phytoplanktons belonging to six families were observed. The other aquatic fauna observed included 14 species of fish, 2 turtles, one leech, one prawn, one shrimp and one bullfrog. The results showed that physico-chemical parameters had an impact …


The Prickly Problem Of Pears Potential Effects Of Native Orthopteran Herbivory On An Invasive Woody Plant, Kaitlin Gawkins Apr 2019

The Prickly Problem Of Pears Potential Effects Of Native Orthopteran Herbivory On An Invasive Woody Plant, Kaitlin Gawkins

Honors Theses

Across the United States, land managers are struggling to cope with a relatively new invasive species, Callery pear (Pyrus calleryana). Callery pear is currently one of the most important invasive species threatening prairies and early successional habitats in Ohio and the Midwest, and yet, no viable means of control exists for this species. This species is relatively resistant to herbicides and resilient against prescribed cutting and burning. One potential management of invasive species is biocontrol, or the intentional introduction of natural enemies to control the growth and propagation of a target organism. Previous experiments with Callery Pear have examined herbivory …


North America Floras, Manuals, & Checklist: A Bibliography, James P. Smith Jr Apr 2019

North America Floras, Manuals, & Checklist: A Bibliography, James P. Smith Jr

Botanical Studies

No abstract provided.


Plant Diet Selectivity And Some Environmental Parameters At Foraging Sites Of Wattled Crane (Bugeranuscarunculatus) In Malagarasi Wetlands, Tanzania, Jasson R.M. John Mar 2019

Plant Diet Selectivity And Some Environmental Parameters At Foraging Sites Of Wattled Crane (Bugeranuscarunculatus) In Malagarasi Wetlands, Tanzania, Jasson R.M. John

Tanzania Journal of Science

Wattled Crane Bugeranuscarunculatusis a threatened wetland-dependent bird species of sub-Saharan Africa with a declining population throughout its range due to habitat degradation. Ecological studies on this species have come from large populations in Botswana and Zambia. Little is known of the isolated small populations, especially those in Tanzania where about 200individuals survive. This study reports observations made on vegetation height, water depth and consumption of plant tubers at foraging locations of the Wattled Crane in Malagarasi-MuyovoziRamsar Site. Foraging birds preferred wet habitats with short vegetation. Birds fed mainly on Pycreusnitidus and Cyperusarticulatusplant tubersbut not those of Eleocharis, a chief food …


Connectivity Explains Local Ant Community Structure In A Neotropical Forest Canopy: A Large‐Scale Experimental Approach, Benjamin J. Adams, Stefan A. Schnitzer, Stephen P. Yanoviak Mar 2019

Connectivity Explains Local Ant Community Structure In A Neotropical Forest Canopy: A Large‐Scale Experimental Approach, Benjamin J. Adams, Stefan A. Schnitzer, Stephen P. Yanoviak

Biological Sciences Faculty Research and Publications

Understanding how habitat structure and resource availability affect local species distributions is a key goal of community ecology. Where habitats occur as a mosaic, variation in connectivity among patches influences both local species richness and composition, and connectivity is a key conservation concern in fragmented landscapes. Similarly, availability of limiting resources frequently determines species coexistence or exclusion. For primarily cursorial arthropods like ants, gaps between neighboring trees are a significant barrier to movement through the forest canopy. Competition for limited resources such as nest sites also promotes antagonistic interactions. Lianas (woody vines) connect normally isolated neighboring tree crowns and often …


Use Of Plumage And Gular Pouch Color To Evaluate Condition Of Oil Spill Rehabilitated California Brown Pelicans (Pelecanus Occidentalis Californicus) Post-Release, Deborah L. Jaques, Kyra L. Mills, Barton G. Selby, Richard R. Veit, Michael H. Ziccardi Feb 2019

Use Of Plumage And Gular Pouch Color To Evaluate Condition Of Oil Spill Rehabilitated California Brown Pelicans (Pelecanus Occidentalis Californicus) Post-Release, Deborah L. Jaques, Kyra L. Mills, Barton G. Selby, Richard R. Veit, Michael H. Ziccardi

Publications and Research

Sublethal effects of oil spills may dampen seabird rehabilitation success due to lingering negative impacts of contamination and stress on reproduction and long-term survival. These effects can be difficult to measure while birds are in care as well as once birds are released. Expression of sexually selected traits that are sensitive to condition can provide information on physiological status of birds. We evaluated plumage molt and gular pouch skin color of California brown pelicans (Pelecanus occidentalis californicus) following oil contamination and rehabilitation to test for differences between previously oiled and rehabilitated (post-spill) and presumably uncontaminated pelicans. Post-spill pelicans released with …


Fecundity Assessment Of Stone Crabs In The Eastern Gulf Of Mexico, Claire E. Crowley, Colin P. Shea, Ryan L. Gandy, Kendra L. Daly Feb 2019

Fecundity Assessment Of Stone Crabs In The Eastern Gulf Of Mexico, Claire E. Crowley, Colin P. Shea, Ryan L. Gandy, Kendra L. Daly

Marine Science Faculty Publications

Accurate estimates of reproductive potential are a key component of any stock assessment. Multiple factors influencing the variability in batch fecundity of stone crabs Menippe spp. across the Florida fishery were quantified with a negative binomial regression model. Stone crabs were collected bimonthly from Cedar Key, Tampa Bay, Pavilion Key, and Sawyer Key from April 2013 through April 2015 for fecundity analysis. Batch fecundity (number of eggs per clutch) was estimated by using dry weights. Modeling results revealed that fecundity was strongly and positively related to carapace width and highly variable among locations, months, and years. Batch fecundity was lowest …


Ocean Robots Uncover Microbial Secrets, Susan Evans, Jim Birch, John A. Breier, Michael V. Jakuba, Mak A. Saito, Julie Robidart Feb 2019

Ocean Robots Uncover Microbial Secrets, Susan Evans, Jim Birch, John A. Breier, Michael V. Jakuba, Mak A. Saito, Julie Robidart

School of Earth, Environmental, & Marine Sciences Faculty Publications

Life on Earth began in the sea, and the oceans continue to support life on our planet. Of particular importance is the ability of marine microbes to exist in a complex web of relationships where substances are continually transformed and exchanged.


Distribution And Population Structure Of The Invasive Nitellopsis Obtusa (Desv. In Loisel.) J. Groves And Native Species Of Characeae In The Northeast U.S.A., Robin Sleith Feb 2019

Distribution And Population Structure Of The Invasive Nitellopsis Obtusa (Desv. In Loisel.) J. Groves And Native Species Of Characeae In The Northeast U.S.A., Robin Sleith

Dissertations, Theses, and Capstone Projects

Freshwater ecosystems are some of the most biologically diverse environments on Earth. Billions of humans rely on functioning freshwater ecosystems for drinking water and many other services. These ecosystems are increasingly threatened by human impacts including nutrient pollution, invasive species, and climate change. Here I contribute four research chapters that investigate freshwater diversity and ecosystem threats using the Characeae, a family of freshwater green macroalgae, as a study system. Characeae are a diverse and ancient group with more than 500 extant species and a fossil history spanning at least 250 million years. These algae are macrophytes in freshwater ecosystems, and …


Wildfire Alters Spatial Patterns Of Available Soil Nitrogen And Understory Environments In A Valley Boreal Larch Forest, Jianjian Kong, Jian Yang, Bo Liu, Lin Qi Jan 2019

Wildfire Alters Spatial Patterns Of Available Soil Nitrogen And Understory Environments In A Valley Boreal Larch Forest, Jianjian Kong, Jian Yang, Bo Liu, Lin Qi

Forestry and Natural Resources Faculty Publications

Wildfire, a primary natural disturbance in many forests, affects soil nutrient availability and spatial distributions of forest plants. However, post-fire changes in soil nutrients and spatial patterns of understory environments at fine scales are poorly understood. Here, we characterized spatial patterns of soil nitrogen availability and site characteristics at a 3-year-post-fire and an unburned site in a valley boreal larch forest. We also examined the relationship between soil nitrogen availability and site characteristics. The results showed that the burned site had higher NO3− and lower NH4+ than the control. The herb, litter and coarse wood debris …


Depth-Dependent Environmental Drivers Of Microbial Plankton Community Structure In The Northern Gulf Of Mexico, Cole Easson, Jose Lopez Jan 2019

Depth-Dependent Environmental Drivers Of Microbial Plankton Community Structure In The Northern Gulf Of Mexico, Cole Easson, Jose Lopez

Biology Faculty Articles

The Gulf of Mexico (GoM) is a dynamic marine ecosystem influenced by multiple natural and anthropogenic processes and inputs, such as the intrusion of warm oligotrophic water via the Loop Current, freshwater and nutrient input by the Mississippi River, and hydrocarbon inputs via natural seeps and industrial spills. Microbial plankton communities are important to pelagic food webs including in the GoM but understanding the drivers of the natural dynamics of these passively distributed microorganisms can be challenging in such a large and heterogeneous system. As part of the DEEPEND consortium, we applied high throughput 16S rRNA sequencing to investigate the …


Volume 4, Chapter 8-7: Tropics: Lowland Rainforests, Janice M. Glime Jan 2019

Volume 4, Chapter 8-7: Tropics: Lowland Rainforests, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.


Volume 4, Chapter 8-9: Tropics: Submontane And Montane, Janice M. Glime Jan 2019

Volume 4, Chapter 8-9: Tropics: Submontane And Montane, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.


Volume 4, Chapter 8-8: Tropics: Elevation, Janice M. Glime Jan 2019

Volume 4, Chapter 8-8: Tropics: Elevation, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.


Volume 4, Chapter 8-11: Tropics: Hydric And Xeric Habitats, Janice M. Glime Jan 2019

Volume 4, Chapter 8-11: Tropics: Hydric And Xeric Habitats, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.


Volume 4, Chapter 8-12: Tropics: Rocks And Inselbergs, Janice M. Glime, Tatiany Oliveira Da Silva Jan 2019

Volume 4, Chapter 8-12: Tropics: Rocks And Inselbergs, Janice M. Glime, Tatiany Oliveira Da Silva

Bryophyte Ecology Subchapters

No abstract provided.