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Estimating Evolutionary Volatility In A Maximum-Likelihood Framework, Samuel Warren Tybout

Graduate Theses, Dissertations, and Problem Reports (ETD)

Evolutionary volatility is a trait that encompasses a clade’s combined capacity for origination and extinction. High volatility increases extinction risk, and declining global extinction rates are thought to be linked to declining volatility. Despite volatility’s scientific importance, there is no standardized way of measuring it. This study provides a new method, derived from a stochastic birth-death model, of estimating evolutionary volatility from fossil data. Simulations indicate that the method produces accurate and precise estimates for large fossil datasets. Analysis of fossil data for five bivalve families (Lucinidae, Mytilidae, Pectinidae, Pholadomyidae, and Veneridae) indicates that diversity projections made from the estimates …

Developmental Mechanisms For The Diversification Of Polyphenic Morphs In The Head Horn Of Onthophagine Beetles (Coleoptera: Scarabaeidae Onthophagus Taurus): Plasticity Through Nutrition, Logan Paul Zeigler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Developmental plasticity is the phenotypic variation between organisms that is caused by environmental interactions affecting the developmental systems of organisms. The research focused primarily on nutrition-responsive developmental plasticity. In this research we used the nutritionally determined head horn development of Onthophagus taurus to better understand the developmental mechanisms and genetic underpinnings of nutrition-responsive trait development. We focused specifically on altering the availability of specific nutrition-related primary metabolites, cholesterol and palmitic acid, identified in the activity of The Hedgehog pathway, a critical pathway in head horn development. By altering diet composition using cholesterol, reducing transcript expression of an acyltransferase gene, rasp …

Habitat Stability In Appalachian Headwater Systems And Potential Impacts On Brook Trout Populations, Zac F.W Zacavish

Graduate Theses, Dissertations, and Problem Reports (ETD)

The impact climate change will have on the habitat for Brook Trout (Salvelinus fontinalis) could directly impact key demographic characteristics. Traditionally, broad-scale studies of climate change effects on the family Salmonidae focus on the thermal shifts predicted over the next century. While some studies shed light onto other variables such as biotic interactions, flow regime, and disturbance, the significance of the climate-trout interaction is not always observed. With the high degree of influence climate cycles can have on habitat and channel morphology, this study aimed to highlight temporal habitat shifts to begin addressing climate-habitat interaction. By studying habitat distribution …

Avian And Salamander Response To Young Forest Management In West Virginia, Eric L. Margenau

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation focuses on the effects of various young forest habitat management techniques on the avian and salamander community in West Virginia. Wildlife species associated with the nascent stage of forest succession are experiencing precipitous population declines throughout much of the eastern United States due to decreases in the amount of young forest area which have been brought on by changes in disturbance regimes over the past century. As a result, the need to find novel approaches for creating young forest habitats to sustain young forest wildlife populations is necessary. However, young forest habitat creation often negatively affects species that …

Leaf Angle And Leaf Stomata Responses To Experimental Drought In Quercus Velutina And Acer Saccharum, Brittany Nichole Casey

Graduate Theses, Dissertations, and Problem Reports (ETD)

The possibility of increased severity and frequency of drought conditions, as a result of global climate variability, greatly complicates our ability to forecast future forest functions such as productivity and carbon sequestration. Assessing how tree species vary in their response to drought can aid in predicting the impact on forest ecosystems as a whole. Throughfall exclusion (TfE) experiments are potentially useful tools to simulate realistic drought conditions within intact forest ecosystems. We employed a TfE experiment during the 2018 growing season within the WV Land Trust’s Elizabeth’s Woods Nature Preserve, near Morgantown, WV, to assess the leaf angle and leaf …

Tree Growth And Water Use Efficiency During The Twentieth Century: From Global Trends To Local Drivers, Justin Michael Mathias

Graduate Theses, Dissertations, and Problem Reports (ETD)

The frequency and severity of extreme environmental conditions will continue to increase under global environmental change. How terrestrial plants respond to prolonged, and often novel environmental stressors, will have profound impacts on, and feedbacks with, the Earth climate system at local to continental scales. Central to these feedbacks are plant stomata, actively regulated pores on the leaves of plants that act as a control valve over the fluxes of carbon dioxide (CO₂) into the leaf during photosynthesis and water vapor (H₂O) out of the leaf during transpiration. Importantly, changes in stomatal aperture do not affect the …

Evolutionary Genomics Of Dynamic Sex Chromosomes In The Salicaceae, Ran Zhou

Graduate Theses, Dissertations, and Problem Reports (ETD)

Identifying the sex-determination region (SDR) and other genomic features of sex chromosomes are of great importance in the studies of the evolution of sex. However, the process of accurately identifying the size and location of the SDR is often difficult, even when a genomic sequence is available. This usually is hindered by large repetitive elements and a lack of recombination in the SDR. In this thesis, I assemble sex chromosomes with whole genomic sequencing data, identify SDRs and explore their genomic features in two sister species from the Salicaceae family. I also develop an interpretation of the lability of the …

The Host Gatekeeper: Using The Flagellar Pathway To Understand Symbiont Host Adaptation, Adam R. Pollio

Graduate Theses, Dissertations, and Problem Reports (ETD)

The acquisition of microbial partners is a strategy used by a diverse group of arthropods to overcome ecological barriers that might normally make certain niches uninhabitable. The unique phylogenetic opportunities attainable from the natural experiment of the Sodalis-allied clade allow for better understanding of how molecular structures evolve through time. Here, we focus on the evolution of the flagellar synthesis pathway, due to its complexity and ability to diverge in response to ecological pressures. We used this molecular pathway and natural experiment to show that normal evolutionary outcomes associated with symbiosis (i.e., genome reduction) do not explain the predicted conservation …

The Effects Of Boring Sponge Infestation On Condition, Growth, And Sex Change In Crepidula Fornicata, Nicole L. Kleinas

College of Graduate Studies: Theses & Dissertations

The Atlantic slipper limpet, Crepidula fornicata, is a sequential hermaphrodite whose size at sex-change is plastic with respect to social and population cues. As an organism allocates energy between growth, reproduction and maintenance, an increased cost of one process may affect another. In this paper, I evaluate whether the presence of an epibiotic sponge (Cliona celata) affects the growth, condition and sex-change of C. fornicata individuals. Population surveys demonstrate a variable effect of Cliona presence on C. fornicata condition. The results of a twelve-week in situ experiment demonstrated a decrease in growth when C. celata was present. …

Predator-Based Selection And The Impact Of Edge Sympatry On Components Of Coralsnake Mimicry, Lauren E. Wilson

College of Graduate Studies: Theses & Dissertations

Studying warning coloration and mimicry is an effective way to understand predator-driven selection and phenotypic diversity. The presence (sympatry) or absence (allopatry) of a toxic model plays a role in shaping mimetic phenotypes. However, the impact of edge sympatry and allopatry on predation of mimetic phenotypes is not well understood. We studied coralsnake mimicry to test how edge sympatry and allopatry affect predation on mimetic phenotypes. Specifically, we tested 1) if overall attack rates varied with edge sympatry of coralsnakes 2) which color patterns conferred a fitness advantage 3) which specific mimetic signal components are important in driving predatory attacks …

Scaling And Ecological Relationships In The Visual Ecology Of Sharks, Brianna Hall

College of Graduate Studies: Theses & Dissertations

Adaptations of visual systems, such as acuity, sensitivity, and eye size can be used to infer the relative importance of vision to an organism. The high metabolic cost of visual system development and maintenance suggests that large relative eye size (as it relates to body length) may have a significant ecological or evolutionary role. Elasmobranchs are morphologically diverse and inhabit a wide range of marine and freshwater niches. As energetic and ecological demands shift over time, several species occupy different predatory niches across their lifetime, yielding a large array of visual habitats. Additionally, eye size changes with body length allometrically, …

Water Sourcing Strategies Of Highly Resilient Vegetation In Desert Soils: Stable Isotope Analysis Of A Northern Chihuahuan Desert Ecosystem, Hayden Eleanor Thompson

Open Access Theses & Dissertations

Plant water use strategies and water transport dynamics are important for understanding ecosystem productivity and soil-vegetation-atmosphere interactions within an environment (Li et al., 2007). Recent research using stable isotope analysis in wet and humid climates has found that vegetation uses tightly particle-bound water stored in the soil that does not participate in translatory flow (Brooks et al., 2010; Goldsmith et al., 2011; McDonnell 2014). In arid and semi-arid deserts of the United States, highly resilient vegetation, such as the Honey Mesquite (Prosopis glandulosa) and the Creosote shrub (Larrea tridentata), exhibit some degree of activity year-round despite limited water availability during …

Novel Tools For Community Based Assessment And Monitoring Of Forest Phenology Response To Environmental Variability And Change In The Tropics, Jennifer Christine Ramos-Chavez

Open Access Theses & Dissertations

Tropical ecosystems provide a variety of services and resources for global well-being. However, landscapes within this biome are undergoing rapid changes mostly due to anthropogenic activities. These systems are further impacted by current, extreme fluctuations in climate, including climate change and El Niño Southern Oscillation (ENSO). With predicted future increase in strength and occurrence of these climate oscillations, these landscapes and their plant communities will be impacted and changed. There is a gap in research and knowledge among tropical Indonesian landscapes in regards to the effects of global climate change at the community level. Therefore, there is an urgent need …

Partitioning Variation In Vegetation And Landscape Functionality In Arid Land Piosphere, Eahsan Shahriary

Open Access Theses & Dissertations

A piosphere is an interaction between vegetation community, watering point, and grazing livestock/wildlife. In this Dissertation, I begin by reviewing the concept of the piosphere, and the progress, knowledge gaps and common statistical approaches and errors in piosphere research. Landscape functionality, plant community distribution and their influencing factors on a piosphere in Iran are then investigated.

A total 862 piosphere publications of multiple types from 68 countries and 10 different languages during the period of 1915 â?? 2018 were reviewed. Australia was the most productive country followed by South Africa, the USA, Botswana and Argentina. Ivan Thrash is the most …

Behavioral Ecology Of A Desert Ambush Predator: Assessing Movement Patterns, Habitat And Microhabitat Use, And The Innate Feeding Response Of Eastern Black-Tailed Rattlesnakes (Crotalus Ornatus) In The Northern Chihuahuan Desert, James Emerson

Open Access Theses & Dissertations

Research on the ecology and evolution of rattlesnakes has been sporadic over the past 80 years, but has seen recent expansion into the diverse fields of physiology, physiological ecology, life history, behavioral ecology, ethology, reproductive biology, chemical ecology, venom biochemistry and medicine, conservation, and many other subdisciplines. The development of small, implantable VHF radiotransmitters in the 1980s revolutionized research in the field of behavioral ecology for rattlesnakes, which are uniquely suited for radiotelemetry studies because they possess several morphological, physiological, and behavioral characteristics that are unique among terrestrial vertebrates. The widespread application of radiotelemetry by the mid-1980s advanced the model …

Specimens Of Opportunity Reveal Novel Information On The Sowerby's Beaked Whale (Mesoplodon Bidens), Kerri Jean Smith

Open Access Theses & Dissertations

Conservation science requires quickly acquiring information and taking action in order to protect species at risk of extinction. Elusive wildlife, however, present challenges to effective conservation measures because it is often difficult to collect enough data on these species to recognize their conservation needs and implement management plans. As a result, researchers must identify alternative means of gathering sufficient data on these species. Specimens of opportunity, such as museum specimens, provide a way to improve knowledge on these species, and these specimens have already proven valuable by increasing information on biodiversity, habitat and range, and population structure in many species. …

Distribution And Evolution Of Fukushima Dai-Ichi Derived 137cs, 90sr, And 129i In Surface Seawater Off The Coast Of Japan, Jennifer A. Kenyon, Ken O. Buesseler, Núria Casacuberta, Maxi Castrillejo, Shigeyoshi Otosaka, Pere Masqué, Jessica A. Drysdale, Steven M. Pike, Virginie Sanial

Research outputs 2014 to 2021

© 2020 American Chemical Society. The Fukushima Dai-ichi Nuclear Power Plants (FDNPPs) accident in 2011 led to an unprecedented release of radionuclides into the environment. Particularly important are 90Sr and 137Cs due to their known health detriments and long half-lives (T1/2 ≈ 30 y) relative to ecological systems. These radionuclides can be combined with the longer-lived 129I (T1/2 = 15.7 My) to trace hydrologic, atmospheric, oceanic, and geochemical processes. This study seeks to evaluate 137Cs, 90Sr, and 129I concentrations in seawater off the coast of Japan, reconcile the sources of contaminated waters, and assess the application of 137Cs/90Sr, 129I/137Cs, and …

Conospermum Undulatum: Insights Into Population Genetics And Pollination Ecology Of A Threatened Species, Nicola Delnevo

Theses: Doctorates and Masters

Fragmentation of natural vegetation is currently one of the largest threats to biodiversity. Within the southwest Australia global biodiversity hotspot, the Swan Coastal Plain was historically cleared for agriculture and forestry and is now experiencing extensive land clearing for urbanisation. The wavy-leaved smokebush Conospermum undulatum is a rare species endemic to the Swan Coastal Plain, and its future persistence is threatened by urban expansion.

Throughout this research, I investigated the pollination ecology of this species and found a specific association between C. undulatum and native bees for pollination. I also demonstrated that C. undulatum has evolved pollen with resistance to …

An Investigation Into The Spatial Distribution, Habitat Selection And Resource Usage Of The Red Fox (Vulpes Vulpes) Inhabiting Urban Reserves Within Perth, Western Australia, Michael Thomas Main

Theses: Doctorates and Masters

I attempted to track a population of urban foxes in Kings Park, but due to collar failure, only one collar was retrieved. The GPS telemetry data from this fox produced home range estimates for minimum convex polygon (MCP) and kernel density (KD) of 0.302 km² and 0.331 km², respectively. The fox was predominantly active at night, with a ten-fold increase in movement during nocturnal periods when compared to daytime movements. Roads and man-made tracks were important for facilitating movement of the fox through its home range, with almost 97% of location fixes recorded within 100m of these features. The fox …

Mdpi Oceans: A New Publication Channel For Open Access Science Focused On The Ocean, Antonio Bode, Fátima Abrantes, Agostinho Antunes, Alvise Benetazzo, Chen-Tung A. Chen, Emmanuel Devred, Martin Gade, Eulàlia Gràcia, Jochen Horstmann, Diego Macías, Joseph M. Maina, Pere Masqué Barri, Nicholas Meskhidze, Luis Somoza

Research outputs 2014 to 2021

The ocean is the most important subsystem of the Earth’s climate system and functions as its heart, regulating the energy distribution of the planet. It has absorbed more than 90% of the energy accumulated since 1971 and about 30% of the emitted anthropogenic carbon dioxide. As a result, water temperature rises and oceans acidify and deoxygenate, which lead to changes in oceanic circulationand biogeochemistry, to rising sea levels, to more extreme weather events, to shifts in the distribution ofspecies and migratory routes, and to loss of species and habitat diversity. Awareness of the importanceof oceans for the sustainability of the …

Morphological And Heartwood Variation Of Santalum Macgregorii In Papua New Guinea, T. Page, G. K. Jeffrey, P. Macdonell, D. Hettiarachchi, Mary C. Boyce, A. Lata, L. Oa, G. Rome

Research outputs 2014 to 2021

© 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Santalum macgregorii (sandalwood), which is endemic to the southern part of Papua New Guinea (PNG), has been heavily exploited for its fragrant heartwood and is classified as threatened across its natural range. Domestication and smallholder agroforestry offer the means to preserve remaining diversity. This study was undertaken to understand the extent of remaining natural variation to support the species’s conservation and domestication. We evaluated morphological, heartwood and essential oil characters in 126 S. macgregorii trees in five populations (districts) in PNG’s Central, Gulf and Western …

The Oceanography And Marine Ecology Of Ningaloo, A World Heritage Area, Mathew A. Vanderklift, Russell C. Babcock, Peter B. Barnes, Anna K. Cresswell, Ming Feng, Michael D. E. Haywood, Thomas H. Holmes, Paul S. Lavery, Richard D. Pillans, Claire B. Smallwood, Damian P. Thomson, Anton D. Tucker, Kelly Waples, Shaun K. Wilson

Research outputs 2014 to 2021

The Ningaloo coast of north-western Australia (eastern Indian Ocean) hosts one of the world’s longest and most extensive fringing coral reef systems, along with globally significant abundances of large marine fauna such as whale sharks. These characteristics – which have contributed to its inscription on the World Heritage list – exist because of the unique climatic, geomorphologic and oceanographic conditions. The region is hot and arid, so runoff of water from land is low, facilitating clear water that allows corals to grow close to the shore. The poleward-flowing Leeuwin Current is an important influence, bringing warm water and generally suppressing …

Management And Population Status Of Kihansi Spray Toad Nectophrynoides Asperginis In Captive Breeding Facilities In Tanzania, Cuthbert L. Nahonyo, Ezekiel M. Goboro, Richard S. Ugomba, Emmanuel S. Nkombe, Severinus Mutagwaba, Hussein Adam, Juma I. Kimera, Person Kalenga, Wilirk Ngalason

Tanzania Journal of Science

Kihansi spray toad Nectophrynoides asperginis was discovered in 1996 in Kihansi gorge. The toad was declared extinct in the wild in 2009 due to habitat alteration. Before its extinction, 499 individuals were flown to the United States of America zoos in 2000 for captive breeding. In 2010, the University of Dar es Salaam, and in 2011 the Kihansi captive breeding facilities were established in Tanzania. The intention was to breed, and reintroduce the toad back to the natural environment in the gorge. The founder populations for the two facilities were sourced from the USA zoos. This study addresses captive management …

Research Work And Conservation Initiatives In The Kihansi Catchment Ecosystem, Tanzania, Cl Nahonyo

Tanzania Journal of Science

Keynote Address  for the Scientific Conference on Research and Conservation Initiatives in the Kihansi Catchment Ecosystem: Successes, Challenges and Way forward held at the National Carbon Monitoring Centre (NCMC), Sokoine University of Agriculture (SUA) on 24 – 27 July 2017.

Reintroduction Of The Kihansi Spray Toad Nectophrynoides Asperginis Back To Its Natural Habitat By Using Acclimatizing Cages, Charles A. Msuya, Nassoro Mohamed

Tanzania Journal of Science

The Kihansi Spray Toad (Nectophrynoides asperginis) is considered to be extinct in the wild. Captive breeding populations exist in Bronx and Toledo zoos in USA and in two captive breeding facilities in Tanzania. Efforts to reintroduce the species back to its natural habitat at Kihansi Gorge wetlands have become a long process. Both ex-situ and in-situ experiments have revealed promising outcomes but when the toads are freely (hard) released in the wetlands they disperse widely and detection becomes difficult.  Cages for acclimatising the toads before hard release have been constructed in two of the Kihansi Gorge spray wetlands. Factors such …

Land Use–Land Cover Change And Implication To Biodiversity In Kihansi Catchment, Phillip K. Mwanukuzi

Tanzania Journal of Science

Land cover-land use (LC-LU) change has significant impact on wetland ecosystem. This study examined the impacts of LC-LU change on spray wetland ecology at Kihansi Gorge and implications to conservation of fragile biodiversity. Remote sensing methods were used to asses land cover changes from 1990 to 2015 and to forecast change in 2035. It was revealed that forests decreased from 28,454 to 10,897 ha and woodland from 26,903 to 19,914 ha. In 1990, woody cover dominated with a total cover of 38% of the entire catchment. The cropland that included grassland and bushland with scattered crops has been on the …

Developmental Transcriptomic Analysis Of The Cave-Dwelling Crustacean, Asellus Aquaticus, Joshua B. Gross, Dennis A. Sun, Brian M. Carlson, Sivan Brodo-Abo, Meredith E. Protas

Natural Sciences and Mathematics | Faculty Scholarship

Cave animals are a fascinating group of species often demonstrating characteristics including reduced eyes and pigmentation, metabolic efficiency, and enhanced sensory systems. Asellus aquaticus, an isopod crustacean, is an emerging model for cave biology. Cave and surface forms of this species differ in many characteristics, including eye size, pigmentation, and antennal length. Existing resources for this species include a linkage map, mapped regions responsible for eye and pigmentation traits, sequenced adult transcriptomes, and comparative embryological descriptions of the surface and cave forms. Our ultimate goal is to identify genes and mutations responsible for the differences between the cave and …

Review Of Megacormus Karsch, 1881, With Description Of A New Species (Scorpiones: Euscorpiidae), František Kovařík

Euscorpius

Megacormus franckei sp. n. from Mexico is described and compared with all other species of the genus. Additional information is provided on the morphology, taxonomy and localities of genus Megacormus, mainly through color photographs of live and preserved specimens of all Megacormus species, as well as their habitats. Included is a key for all six known species of the genus Megacormus

Snowpack Properties Vary In Response To Burn Severity Gradients In Montane Forests, Jordan Maxwell, Samuel B. St. Clair

Aspen Bibliography

Wildfires are altering ecosystems globally as they change in frequency, size, and severity. As wildfires change vegetation structure, they also alter moisture inputs and energy fluxes which influence snowpack and hydrology. In unburned forests, snow has been shown to accumulate more in small clearings or in stands with low to moderate forest densities. Here we investigate whether peak snowpack varies with burn severity or percent overstory tree mortality post-fire in a mid-latitude, subalpine forest. We found that peak snowpack across the burn severity gradients increased 15% in snow-water equivalence (SWE) and 17% in depth for every 20% increase in overstory …

Assessment Of Tree Species Richness, Diversity, Population Structure And Natural Regeneration In Nongeni Forest Reserve In Morogoro Region, Tanzania, David Sylvester Kacholi

Tanzania Journal of Science

This study examined tree species richness, diversity, population structure and regeneration in Nongeni forest reserve, Morogoro, Tanzania. The study deployed plot sampling technique whereby a total of 20 plots of 0.05 ha each were randomly established in the forest. All species and individuals encountered in each plot were counted, identified and DBH measured. A total of 751 individuals/ha representing 24 species belonging to 11 families were recorded. Family Fabaceae was dominant with 9 species. The Shannon-Wiener, Margalef, Simpson’s and Pielou J index were calculated as 2.667, 3.474, 10.58 and 0.839, respectively. The Diplorhynchus condylocarpon (52.18) was the dominant species in …