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Articles 481 - 510 of 890
Full-Text Articles in Entire DC Network
Movement And Habitat Use Of The Snapping Turtle In An Urban Landscape, Travis J. Ryan, William A. Peterman, Jessica D. Stephens, Sean C. Sterrett
Movement And Habitat Use Of The Snapping Turtle In An Urban Landscape, Travis J. Ryan, William A. Peterman, Jessica D. Stephens, Sean C. Sterrett
Scholarship and Professional Work - LAS
In order to effectively manage urban habitats, it is important to incorporate the spatial ecology and habitat use of the species utilizing them. Our previous studies have shown that the distribution of upland habitats surrounding a highly urbanized wetland habitat, the Central Canal (Indianapolis, IN, USA) influences the distribution of map turtles (Graptemys geographica) and red-eared sliders (Trachemys scripta) during both the active season and hibernation. In this study we detail the movements and habitat use of another prominent member of the Central Canal turtle assemblage, the common snapping turtle, Chelydra serpentina. We find the same …
The Distribution Of Fruit And Seed Toxicity During Development For Eleven Neotropical Trees And Vines, Noelle G. Beckman
The Distribution Of Fruit And Seed Toxicity During Development For Eleven Neotropical Trees And Vines, Noelle G. Beckman
Biology Faculty Publications
Secondary compounds in fruit mediate interactions with natural enemies and seed dispersers, influencing plant survival and species distributions. The functions of secondary metabolites in plant defenses have been well-studied in green tissues, but not in reproductive structures of plants. In this study, the distribution of toxicity within plants was quantified and its influence on seed survival was determined in Central Panama. To investigate patterns of allocation to chemical defenses and shifts in allocation with fruit development, I quantified variation in toxicity between immature and mature fruit and between the seed and pericarp for eleven species. Toxicity of seed and pericarp …
Bactericera Cockerelli: Range Expansion, Candidatus Liberibacter Solanacaerum Detection, And Microbial Community Analysis, Alex Arp
Biology Theses
The potato psyllid (Bactericera cockerelli) is an emerging pest of solanacious crops. Traditionally their range expanded from Guatemala north through the central United States and into southern California. Recent expansions have led to potato psyllids residing as far south as Nicaragua and as for north as Washington State. Potato psyllids were also accidentally imported into New Zealand. These expansions are alarming because potato psyllids transmit Candidatus Liberibacter solanacaerum (Lso), the bacteria associated with Zebra Chip disease in potato, which results in millions of dollars in damages annually. In this study, potato psyllid and Zebra Chip range expansion into Central America …
Ground-Truthing Maxent In East Texas Rivers, David F. Ford
Ground-Truthing Maxent In East Texas Rivers, David F. Ford
Biology Theses
Unionid mussels are a guild of freshwater, sedentary filter-feeders, which play a critical role in freshwater systems. Mussels are currently experiencing a global decline in both species richness and abundance, due to invasive species, human alteration of water systems, and climate change. In North America, which is considered to have the highest global diversity of bivalve species, native mussels are currently declining rapidly with at least 37 species considered to already be extinct. If extant mussel species are to be preserved, then it is vital that conservation efforts be prioritized towards areas in which they are likely to be found. …
The Identity Of Rana Margaritifera Laurenti, 1768 (Anura, Bufonidae), Esteban O. Lavilla, Ulisses Caramaschi, José A. Langone, José P. Pombal Jr., Rafael O. De Sá
The Identity Of Rana Margaritifera Laurenti, 1768 (Anura, Bufonidae), Esteban O. Lavilla, Ulisses Caramaschi, José A. Langone, José P. Pombal Jr., Rafael O. De Sá
Biology Faculty Publications
Rana margaritifera was described by Laurenti in 1768 and currently is associated to the genus Rhinella, under the combination Rhinella margaritifera. Currently, the R. margaritifera species group consists of 16 recognized species. Further-more, many additional species have been suggested to exist in this group which highlights the ambiguity surrounding the identity of Rhinella margaritifera and impend further description of the species in this group. After an exhaustive bibliographic review, we concluded that the recent designation of a lectotype for R. margaritifera is invalid according with Art. 73, ICZN, 1999. Herein, we designate and provide the description of a …
Exploring Signals Of Historical Demography In Boreal Mammals Through Integration Of Statistical Conservation Phylogenetics, Taxonomy, And Comparative Phylogeography, Jason L. Malaney
Biology ETDs
Understanding how diversity is partitioned across the landscape can provide perspectives related to the environmental processes that have influenced the evolutionary history of organisms. This main idea, often termed phylogeography, serves as the backdrop to my research where I explore three broad concepts including historical biogeography, cryptic diversity and ecology, and conservation phylogenetics. I address various questions in each of these concepts by using a set of mammals that are associated with montane and mesic environments of North America. More specifically, I focus on the jumping mice (Zapodidae) to test hypotheses that scale to the broader community. This approach allows …
Examining Mitochondrial Genetic Diversity In A Population Of Eastern Hognose Snakes (Heterodon Platirhinos) In Cape Cod, Ma, Stephanie R. Parelli
Examining Mitochondrial Genetic Diversity In A Population Of Eastern Hognose Snakes (Heterodon Platirhinos) In Cape Cod, Ma, Stephanie R. Parelli
Theses, Dissertations and Culminating Projects
The Eastern Hognose snake (Heterodon platirhinos) is a relatively poorly studied species found in the eastern half of the United States from southern New England and Ontario south along the Atlantic coast to Florida and west to Texas, Kansas, Nebraska, and South Dakota. In the Northeastern part of their range they are considered to be a species of regional conservation concern by the Northeast Endangered Species and Wildlife Diversity Technical Committee. They are protected by conservation measures in the states of Rhode Island, Connecticut, and Massachusetts, and are listed as endangered by the state of New Hampshire. The purpose of …
Influence Of Wind Turbines On Mammalian Occupancy Patterns, Brian P. Tanis
Influence Of Wind Turbines On Mammalian Occupancy Patterns, Brian P. Tanis
Master's Theses or Doctor of Nursing Practice
Wind energy is among the most rapidly growing energy industries in the United States, with support for development coming from both state and federal governments. While the industry depicts an environmentally friendly image, the addition of infrastructure associated with wind farms alters landscapes in novel ways. Numerous studies have documented impacts wind turbines have on bird and bat mortality; however, far less attention has been directed towards responses of non-volant, terrestrial organisms. Mammalian mesocarnivores are model organisms to assess the alteration of communities surrounding wind turbines as they respond to addition of turbines and human activity, addition and improvement of …
Variations In Phenotypic Plasticity And Fluctuating Asymmetry Of Leaf Morphology Of Three Quercus (Oak) Species In Response To Environmental Factors, Joseph Kusi
Electronic Theses and Dissertations
Leaf morphology of Quercus (oak) species is highly variable and complicated confounded with phenotypic plasticity and fluctuating asymmetry (FA). However, the study of variation is mostly limited to leaf morphology. This study was extended to plasticity and FA variations in Q. alba (white oak), Q. palustris (pin oak), and Q. velutina (black oak). It was hypothesized that light exposure, individual trees, leaf position, and other leaf traits will influence variation in these species. Leaves were sampled from trees of these species and their morphological traits were measured. Absolute asymmetry of leaf width and area were determined and plasticity of each …
An Environmental History Of The Bear River Range, 1860-1910, Bradley Paul Hansen
An Environmental History Of The Bear River Range, 1860-1910, Bradley Paul Hansen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The study of environmental history suggests that nature and culture change all the time, but that the rate and scale of such change can vary enormously. During the late 19th and early 20th centuries, Anglo settlement in the American West transformed landscapes and ecologies, creating new and complex environmental problems. This transformation was particularly impressive in Cache Valley, Utah's Bear River Range. From 1860 to 1910, Mormon settlers overused or misused the Bear River Range's lumber, grazing forage, wild game, and water resources and introduced invasive plant and animal species throughout the area.
By the turn of the 20th century, …
A Data-Intensive Assessment Of The Species Abundance Distribution, Elita Baldridge
A Data-Intensive Assessment Of The Species Abundance Distribution, Elita Baldridge
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
One of the most commonly observed patterns in ecology is the fact that at most locations there are a large number of relatively rare species, composed of only a few individuals per species, and a small number of relatively common species. This pattern of commonness and rarity is quantified by the species abundance distribution. As one of the most commonly observed patterns in ecology, it has been studied intensively for over 100 years.
A major emphasis of this research has been developing models to try to understand the forces that generate such a general pattern. As a result, there are …
Activities Of Methionine-Γ-Lyase In The Acidophilic Archaeon “Ferroplasma Acidarmanus” Strain Fer1, M. A. Khan, Madeline M. Lopez-Munoz, Charles W. Kaspar, Kai F. Hung
Activities Of Methionine-Γ-Lyase In The Acidophilic Archaeon “Ferroplasma Acidarmanus” Strain Fer1, M. A. Khan, Madeline M. Lopez-Munoz, Charles W. Kaspar, Kai F. Hung
Faculty Research & Creative Activity
Biogeochemical processes on exposed pyrite ores result in extremely high levels of sulfuric acid at these locations. Acidophiles that thrive in these conditions must overcome significant challenges, including an environment with proton concentrations at pH 3 or below. The role of sulfur metabolism in the archaeon “Ferroplasma acidarmanus” strain fer1’s ability to thrive in this environment was investigated due to its growth-dependent production of methanethiol, a volatile organic sulfur compound. Two putative sequences for methionine- γ-lyase (EC 4.4.1.11), an enzyme known to carry out α,γ-elimination on L-methionine to produce methanethiol, were identified in fer1. Bioinformatic analyses identified a conserved pyridoxal-5′-phosphate …
A Pharm-Ecological Perspective Of Terrestrial And Aquatic Plant-Herbivore Interactions, Jennifer Sorensen Forbey, M. Denise Dearing, Elisabeth M. Gross, Colin M. Orians, Erik E. Sotka, William J. Foley
A Pharm-Ecological Perspective Of Terrestrial And Aquatic Plant-Herbivore Interactions, Jennifer Sorensen Forbey, M. Denise Dearing, Elisabeth M. Gross, Colin M. Orians, Erik E. Sotka, William J. Foley
Biology Faculty Publications and Presentations
We describe some recent themes in the nutritional and chemical ecology of herbivores and the importance of a broad pharmacological view of plant nutrients and chemical defenses that we integrate as “Pharm-ecology”. The central role that dose, concentration, and response to plant components (nutrients and secondary metabolites) play in herbivore foraging behavior argues for broader application of approaches derived from pharmacology to both terrestrial and aquatic plant-herbivore systems. We describe how concepts of pharmacokinetics and pharmacodynamics are used to better understand the foraging phenotype of herbivores relative to nutrient and secondary metabolites in food. Implementing these concepts into the field …
Functional Annotation And Comparative Analysis Of A Zygopteran Transcriptome, Alexander G. Shanku, Mark A. Mcpeek, Andrew D. Kern
Functional Annotation And Comparative Analysis Of A Zygopteran Transcriptome, Alexander G. Shanku, Mark A. Mcpeek, Andrew D. Kern
Dartmouth Scholarship
In this paper we present a de novo assembly of the transcriptome of the damselfly (Enallagma hageni) through the use of 454 pyrosequencing. E. hageni is a member of the suborder Zygoptera, in the order Odonata, and Odonata organisms form the basal lineage of the winged insects (Pterygota). To date, sequence data used in phylogenetic analysis of Enallagma species have been derived from either mitochondrial DNA or ribosomal nuclear DNA. This Enallagma transcriptome contained 31,661 contigs that were assembled and translated into 14,813 individual open reading frames. Using these data, we constructed an extensive dataset of 634 orthologous nuclear protein-encoding …
Assessing Multiple Endpoints Of Atrazine Ingestion On Gravid Northern Watersnakes (Nerodia Sipedon) And Their Offspring, Lorin A. Neuman-Lee, Karen F. Gaines, Kyle A. Baumgartner, Jayme R. Voorhees, James M. Novak, Stephen J. Mullin
Assessing Multiple Endpoints Of Atrazine Ingestion On Gravid Northern Watersnakes (Nerodia Sipedon) And Their Offspring, Lorin A. Neuman-Lee, Karen F. Gaines, Kyle A. Baumgartner, Jayme R. Voorhees, James M. Novak, Stephen J. Mullin
Faculty Research & Creative Activity
Ecotoxicological studies that focus on a single endpoint might not accurately and completely represent the true ecological effects of a contaminant. Exposure to atrazine, a widely used herbicide, disrupts endocrine function and sexual development in amphibians, but studies involving live-bearing reptiles are lacking. This study tracks several effects of atrazine ingestion from female Northern Watersnakes (Nerodia sipedon) to their offspring exposed in utero. Twenty-five gravid N. sipedon were fed fish dosed with one of the four levels of atrazine (0, 2, 20, or 200 ppb) twice weekly for the entirety of their gestation period. Endpoints for the mothers included blood …
Trophic Ecology Of A Freshwater Sponge (Spongilla Lacustris) Revealed By Stable Isotope Analysis, J Skelton, Mac Strand
Trophic Ecology Of A Freshwater Sponge (Spongilla Lacustris) Revealed By Stable Isotope Analysis, J Skelton, Mac Strand
Faculty Works
No abstract provided.
International Polar Year (Ipy) Back To The Future (Btf): Changes In Arctic Ecosystem Structure Over Decadal Times Scales, Sandra Villarreal
International Polar Year (Ipy) Back To The Future (Btf): Changes In Arctic Ecosystem Structure Over Decadal Times Scales, Sandra Villarreal
Open Access Theses & Dissertations
Arctic vegetation communities are responding to climate warming through shifts in species composition and diversity but most observations have been made over relatively short time frames, and/or in association with experimental manipulations. Because vegetation plays a key role in regulating ecosystem productivity, nutrient cycling, surface energy budgets, and trophic interactions in the Arctic, there is a need to better understand shifts in tundra vegetation communities over decadal time scales. Understanding these shifts and their impact on ecosystem structure and function in the Arctic has important implications for predicting the future state of both the Arctic and the Earth System. Long …
Hand Pulling Following Mowing And Herbicide Treatments Increases Control Of Spotted Knapweed (Centaurea Stoebe), Neil W. Macdonald, Laurelin M. Martin, Corey K. Kapolka, Timothy F. Botting, Tami E. Brown
Hand Pulling Following Mowing And Herbicide Treatments Increases Control Of Spotted Knapweed (Centaurea Stoebe), Neil W. Macdonald, Laurelin M. Martin, Corey K. Kapolka, Timothy F. Botting, Tami E. Brown
Peer Reviewed Publications
Extensive areas in the upper Midwest have been invaded by spotted knapweed, and effective management strategies are required to reestablish native plant communities. We examined effects of mowing, mowing plus clopyralid, or mowing plus glyphosate in factorial combination with hand pulling and burning on knapweed abundances on a knapweed-infested site in western Michigan. We applied mowing and herbicide treatments in summer 2008, and seeded all plots with native grasses and forbs in spring 2009. We conducted the knapweed pulling treatment from 2009 to 2012 in July. The prescribed burn was conducted in April 2012. By 2012, hand pulling reduced adult …
Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall
Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall
Biological Sciences Faculty Publications
This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations. With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as meso- or eutrophic. Among the cyanobacteria were 6 known toxin producers (Anabaena circinalis, Anabaena spiroides, Aphanizomenon flos-aquae, Cylindrospermopsis raciborskii, Limnothrix redekei, and Microcystis aeruginosa). The study characterizes phytoplankton populations in these aging freshwater habitats taken from a large number …
Habitat Use And Feeding Ecology Of Delphinids Inferred From Stable Isotopes And Fatty Acid Signatures, Nicole Browning
Habitat Use And Feeding Ecology Of Delphinids Inferred From Stable Isotopes And Fatty Acid Signatures, Nicole Browning
Electronic Theses and Dissertations
Prey availability, directly or indirectly, affects all aspects of a predator’s life history and is a primary factor influencing habitat selection and movements. This is especially true for delphinid species where it has been documented that the behaviors and movements of dolphins are strongly influenced by food availability. Unfortunately, the feeding ecology and habitat use patterns of many of these species are poorly understood. Many methodologies that have been employed to explore these facets of dolphin ecology have limitations and constraints or are logistically infeasible. Stable isotope and fatty acid signature analyses have been used extensively on a wide variety …
A Comprehensive Research Framework For Geographic Parthenogenesis In Whiptail Lizards (Genus Aspidoscelis), Adam Leland
A Comprehensive Research Framework For Geographic Parthenogenesis In Whiptail Lizards (Genus Aspidoscelis), Adam Leland
UNLV Theses, Dissertations, Professional Papers, and Capstones
One of the most compelling topics in biology has been the ubiquity of sexual reproduction in living organisms. Because the ecological and evolutionary advantages of sex are well founded, those organisms that reproduce asexually remain enigmatic. Parthenogenesis, the clonal reproduction of an all-female species without the need for males, is a relatively common form of asexual reproduction in vertebrates, and has been subject of numerous academic investigations. Many parthenogenic organisms also share aspects of their geographic distributions, such as inhabiting higher latitudes, higher altitudes, islands or island-like habitats, xeric environments, and marginal, disturbed or ecotonal habitats relative to their sexual …
Regional Contingencies In The Relationship Between Aboveground Biomass And Litter In The World’S Grasslands, Lydia R. O’Halloran, Elizabeth T. Borer, Eric W. Seabloom, Andrew S. Macdougall, Elsa E. Cleland, Rebecca L. Mcculley, Sarah Hobbie, W. Stanley Harpole, Nicole M. Decrappeo, Chengjin Chu, Jonathan D. Bakker, Kendi F. Davies, Guozhen Du, Jennifer Firn, Nicole Hagenah, Kirsten S. Hofmockel, Johannes Knops, Wei Li, Brett A. Melbourne, John W. Morgan, John L. Orrock, Suzanne M. Prober, Carly J. Stevens
Regional Contingencies In The Relationship Between Aboveground Biomass And Litter In The World’S Grasslands, Lydia R. O’Halloran, Elizabeth T. Borer, Eric W. Seabloom, Andrew S. Macdougall, Elsa E. Cleland, Rebecca L. Mcculley, Sarah Hobbie, W. Stanley Harpole, Nicole M. Decrappeo, Chengjin Chu, Jonathan D. Bakker, Kendi F. Davies, Guozhen Du, Jennifer Firn, Nicole Hagenah, Kirsten S. Hofmockel, Johannes Knops, Wei Li, Brett A. Melbourne, John W. Morgan, John L. Orrock, Suzanne M. Prober, Carly J. Stevens
School of Biological Sciences: Faculty Publications
Based on regional-scale studies, aboveground production and litter decomposition are thought to positively covary, because they are driven by shared biotic and climatic factors. Until now we have been unable to test whether production and decomposition are generally coupled across climatically dissimilar regions, because we lacked replicated data collected within a single vegetation type across multiple regions, obfuscating the drivers and generality of the association between production and decomposition. Furthermore, our understanding of the relationships between production and decomposition rests heavily on separate meta-analyses of each response, because no studies have simultaneously measured production and the accumulation or decomposition of …
Diversification Under Sexual Selection: The Relative Roles Of Mate Preference Strength And The Degree Of Divergence In Mate Preferences, Rafael L. Rodríguez, Janette W. Boughman, David A. Gray, Eileen A. Hebets, Gerlinde Höbel, Laurel B. Symes
Diversification Under Sexual Selection: The Relative Roles Of Mate Preference Strength And The Degree Of Divergence In Mate Preferences, Rafael L. Rodríguez, Janette W. Boughman, David A. Gray, Eileen A. Hebets, Gerlinde Höbel, Laurel B. Symes
Eileen Hebets Publications
The contribution of sexual selection to diversification remains poorly understood after decades of research. This may be in part because studies have focused predominantly on the strength of sexual selection, which offers an incomplete view of selection regimes. By contrast, students of natural selection focus on environmental differences that help compare selection regimes across populations. To ask how this disparity in focus may affect the conclusions of evolutionary research, we relate the amount of diversification in mating displays to quantitative descriptions of the strength and the amount of divergence in mate preferences across a diverse set of case studies of …
Long-Term Nitrogen Amendment Alters The Diversity And Assemblage Of Soil Bacterial Communities In Tallgrass Prairie, Joseph D. Coolon, Kenneth L. Jones, Timothy C. Todd, John M. Blair, Michael A. Herman
Long-Term Nitrogen Amendment Alters The Diversity And Assemblage Of Soil Bacterial Communities In Tallgrass Prairie, Joseph D. Coolon, Kenneth L. Jones, Timothy C. Todd, John M. Blair, Michael A. Herman
School of Biological Sciences: Faculty Publications
Anthropogenic changes are altering the environmental conditions and the biota of ecosystems worldwide. In many temperate grasslands, such as North American tallgrass prairie, these changes include alteration in historically important disturbance regimes (e.g., frequency of fires) and enhanced availability of potentially limiting nutrients, particularly nitrogen. Such anthropogenically-driven changes in the environment are known to elicit substantial changes in plant and consumer communities aboveground, but much less is known about their effects on soil microbial communities. Due to the high diversity of soil microbes and methodological challenges associated with assessing microbial community composition, relatively few studies have addressed specific taxonomic changes …
Nitrogen Uptake Strategies Of Edaphically Specialized Bornean Tree Species, Sabrina E. Russo, Amy Kochsiek, Jocelyn Olney, Lauren Thompson, Amy E. Miller, Sylvester Tan
Nitrogen Uptake Strategies Of Edaphically Specialized Bornean Tree Species, Sabrina E. Russo, Amy Kochsiek, Jocelyn Olney, Lauren Thompson, Amy E. Miller, Sylvester Tan
School of Biological Sciences: Faculty Publications
The association of tree species with particular soil types contributes to high b diversity in forests, but the mechanisms producing such distributions are still debated. Soil nitrogen (N) often limits growth and occurs in differentially available chemical forms. In a Bornean forest where tree species composition changes dramatically along a soil gradient varying in supplies of different N-forms, we investigated whether tree species’ N-uptake and soil specialization strategies covaried. We analyzed foliar 15N natural abundance for a total of 216 tree species on clay or sandy loam (the soils at the gradient’s extremes) and conducted a 15N-tracer experiment …
Large-Scale Spatial Synchrony And Cross-Synchrony In Acorn Production By Two California Oaks, Walter D. Koenig, Johannes M.H. Knops
Large-Scale Spatial Synchrony And Cross-Synchrony In Acorn Production By Two California Oaks, Walter D. Koenig, Johannes M.H. Knops
School of Biological Sciences: Faculty Publications
Seed production that varies greatly from year to year, known as ‘‘masting’’ or ‘‘mast-fruiting’’ behavior, is a population-level phenomenon known to exhibit geographic synchrony extending, at least in some cases, hundreds of kilometers. The two main nonexclusive hypotheses for the driver of such geographically extensive synchrony are (1) environmental factors (the Moran effect), and (2) the mutual dependence of trees on outcrossed pollen (pollen coupling). We tested 10 predictions relevant to these two hypotheses using 18 years of acorn production data on two species of California oaks. Data were obtained across the entire ranges of the two species at 12 …
An Investigation Of The Factors Leading To Invasion Success Of Non-Native Plants Using A System Of Native, Introduced Non-Invasive, And Invasive Eugenia Congeners In Florida, Kerry Bohl
USF Tampa Graduate Theses and Dissertations
The overwhelming majority of plant species introduced into a new range never become invasive. Consequently, identification of factors allowing the small fraction of successful invaders to naturalize, increase in abundance, and displace resident species continues to be a key area of research in invasion biology. Of the considerable number of hypotheses that have been proposed to resolve why some plant species become noxious pests, the enemy release hypothesis (ERH) is one of the most commonly cited. The ERH maintains that invasive plants succeed in a new range because they are no longer regulated by their coevolved natural enemies, and this …
Associational Resistance And Competition In The Asphondylia - Borrichia - Iva System, Keith Stokes
Associational Resistance And Competition In The Asphondylia - Borrichia - Iva System, Keith Stokes
USF Tampa Graduate Theses and Dissertations
Indirect ecological effects such as associational resistance and resource competition have the potential to affect ecological interactions and influence the structure of ecological communities. Although resource competition is commonly studied, the effects of associational resistance are not as evident if studies are not designed to detect them. Additionally, the relative strengths of different ecological mechanisms ought to be measured in studies, rather than the strength of singular mechanisms. This permits proper attribution of causes and effects in community structure and detection of higher order interactions in a way that naïve reductionism will not.
In a series of experiments, I looked …
Effects Of Site Preparation, Seed Germination, And Harvest Maturity On Wiregrass Restoration Efforts At Fort Stewart, Ga, Nickey Garrett Anderson
Effects Of Site Preparation, Seed Germination, And Harvest Maturity On Wiregrass Restoration Efforts At Fort Stewart, Ga, Nickey Garrett Anderson
College of Graduate Studies: Theses & Dissertations
Wiregrass (Aristida stricta Michx.) was once the dominant ground cover species within the Atlantic Coastal Plain longleaf pine (Pinus palustris Mill.) ecosystem. Less than 1 million hectares of intact longleaf pine-wiregrass communities remain, due primarily to anthropogenic activities. Wiregrass is a keystone species in the longleaf pine ecosystem, as its presence facilitates the natural fire regime, a critical component in the perpetuation of these communities. Therefore, there is increased interest in wiregrass restoration in both existing longleaf pine communities and future longleaf pine restoration sites. Many restoration sites are on tracts that have been cleared of all vegetation. Removal of …
Propulsion In Cubomedusae: Mechanisms And Utility, Sean Colin, John H. Costello, Kakani Katija, Jamie Seymour, Kristen Kiefer
Propulsion In Cubomedusae: Mechanisms And Utility, Sean Colin, John H. Costello, Kakani Katija, Jamie Seymour, Kristen Kiefer
Arts & Sciences Faculty Publications
Evolutionary constraints which limit the forces produced during bell contractions of medusae affect the overall medusan morphospace such that jet propulsion is limited to only small medusae. Cubomedusae, which often possess large prolate bells and are thought to swim via jet propulsion, appear to violate the theoretical constraints which determine the medusan morphospace. To examine propulsion by cubomedusae, we quantified size related changes in wake dynamics, bell shape, swimming and turning kinematics of two species of cubomedusae, Chironex fleckeri and Chiropsella bronzie. During growth, these cubomedusae transitioned from using jet propulsion at smaller sizes to a rowing-jetting hybrid mode …