Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Ecology and Evolutionary Biology

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 13561 - 13590 of 19722

Full-Text Articles in Entire DC Network

New Species Of Arostrilepis (Eucestoda: Hymenolepididae) In Members Of Cricetidae And Geomyidae (Rodentia) From The Western Nearctic, Arseny A. Makarikov, Scott Lyell Gardner, Eric P. Hoberg Jan 2012

New Species Of Arostrilepis (Eucestoda: Hymenolepididae) In Members Of Cricetidae And Geomyidae (Rodentia) From The Western Nearctic, Arseny A. Makarikov, Scott Lyell Gardner, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Specimens originally identified as Arostrilepis horrida from the Nearctic are revised, contributing to the recognition of a complex of cryptic species distributed across the Holarctic region. Previously unrecognized species are described based on specimens in cricetid (Neotominae) and geomyid rodents. Arostrilepis mariettavogeae n. sp. in Peromyscus californicus from Monterey County, California, and Arostrilepis schilleri n. sp. in Thomomys bulbivorus from Corvallis, Oregon, are characterized. Consistent with recent studies defining diversity in the genus, form, size, and spination (pattern, shape, and size) of the cirrus are diagnostic; species are further distinguished by the relative position and length of the cirrus sac …


Return To Beringia: Parasites Reveal Cryptic Biogeographic History Of North American Pikas, Kurt E. Galbreath, Eric P. Hoberg Jan 2012

Return To Beringia: Parasites Reveal Cryptic Biogeographic History Of North American Pikas, Kurt E. Galbreath, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Traditional concepts of the Bering Land Bridge as a zone of predominantly eastward expansion from Eurasia and a staging area for subsequent colonization of lower latitudes in North America led to early inferences regarding biogeographic histories of North American faunas, many of which remain untested. Here we apply a host–parasite comparative phylogeographical (HPCP) approach to evaluate one such history, by testing competing biogeographic hypotheses for five lineages of host-specific parasites shared by the collared pika (Ochotona collaris) and American pika (Ochotona princeps) of North America. We determine whether the southern host species (O. princeps) …


Discovery And Description Of The "Davtiani" Morphotype For Teladorsagia Boreoarcticus (Trichostrongyloidea: Ostertagiinae) Abomasal Parasites In Muskoxen, Ovibos Moschatus, And Caribou, Rangifer Tarandus, From The North American Arctic: Implications For Parasite Faunal Diversity, Eric P. Hoberg, Arthur Abrams, Patricia A. Pilitt, Susan J. Kutz Jan 2012

Discovery And Description Of The "Davtiani" Morphotype For Teladorsagia Boreoarcticus (Trichostrongyloidea: Ostertagiinae) Abomasal Parasites In Muskoxen, Ovibos Moschatus, And Caribou, Rangifer Tarandus, From The North American Arctic: Implications For Parasite Faunal Diversity, Eric P. Hoberg, Arthur Abrams, Patricia A. Pilitt, Susan J. Kutz

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Collections to explore helminth diversity among free-ranging ungulates in the North American Arctic revealed the occurrence of a third male, or "davtiani," morphotype for Teladorsagia boreoarcticus. Designated as T. boreoarcticus forma (f.) minor B, the males occurred with T. boreoarcticus f. major and T. borearcticus f. minor A in endemic populations of muskoxen (Ovibos moschatus wardi) and barrenground caribou (Rangifer tarandus groenlandicus) on Victoria Island, Nunavut, Canada, and in muskoxen and Peary caribou (Rangifer tarandus pearyi) on Banks Island, Northwest Territories, Canada. These specimens differ from conspecific morphotypes in the structure …


Discovery And Description Of A New Trichostrongyloid Species (Nematoda: Ostertagiinaw), Abomasal Parasites In Mountain Goat, Oreamnos Americanus, From The Western Cordillera Of North America [With Erratum], Eric P. Hoberg, Arthur Abrams, Patricia A. Pilitt, Emily J. Jenkins Jan 2012

Discovery And Description Of A New Trichostrongyloid Species (Nematoda: Ostertagiinaw), Abomasal Parasites In Mountain Goat, Oreamnos Americanus, From The Western Cordillera Of North America [With Erratum], Eric P. Hoberg, Arthur Abrams, Patricia A. Pilitt, Emily J. Jenkins

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Marshallagia lichtenfelsi sp. n. is a dimorphic ostertagiine nematode occurring in the abomasum of mountain goats, Oreamnos americanus, from the Western Cordillera of North America. Major and minor morphotype males and females are characterized and distinguished relative to the morphologically similar Marshallagia marshalli/Marshallagia occidentalis from North America and Marshallagia dentispicularis, along with other congeners, from the Palearctic region. The configuration of the convoluted and irregular synlophe in the cervical region of males and females of M. lichtenfelsi is apparently unique, contrasting with a continuous and parallel system of ridges among those species of Marshallagia, including …


Genetic Diversity Of Neotropical Myotis (Chiroptera: Vespertilionidae) With An Emphasis On South American Species, Roxanne J. Larsen, Michelle C. Knapp, Hugh H. Genoways, Faisal Ali Anwarali Khan, Peter A. Larsen, Don E. Wilson, Robert J. Baker Jan 2012

Genetic Diversity Of Neotropical Myotis (Chiroptera: Vespertilionidae) With An Emphasis On South American Species, Roxanne J. Larsen, Michelle C. Knapp, Hugh H. Genoways, Faisal Ali Anwarali Khan, Peter A. Larsen, Don E. Wilson, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

Background: Cryptic morphological variation in the Chiropteran genus Myotis limits the understanding of species boundaries and species richness within the genus. Several authors have suggested that it is likely there are unrecognized species-level lineages of Myotis in the Neotropics. This study provides an assessment of the diversity in New World Myotis by analyzing cytochrome-b gene variation from an expansive sample ranging throughout North, Central, and South America. We provide baseline genetic data for researchers investigating phylogeographic and phylogenetic patterns of Myotis in these regions, with an emphasis on South America.

Methodology and Principal Findings: Cytochrome-b sequences were …


Synthesizing Parasitology With Archaeology In Paleopathology, Karl Reinhard, Adauto Araujo Jan 2012

Synthesizing Parasitology With Archaeology In Paleopathology, Karl Reinhard, Adauto Araujo

Karl Reinhard Publications

Parasitology is the study of organisms that are symbiotic with other organisms. In this form of symbiosis, the parasite species by definition benefits from the interaction while the host is harmed to some degree. In actuality, some parasites benefit their hosts. The animals traditionally studied by parasitologists range from protozoa to arthropods, and include all types of internal and external worms. Ticks, fleas, lice, and a variety of insects that transmit parasites are also studied by parasitologists. Recently, a more holistic view of parasitism appeared, including bacteria and viruses. In essence, parasitology is the study of a certain kind of …


Patterns Of Extinction Risk And Threat For Marine Vertebrates And Habitat-Forming Species In The Tropical Eastern Pacific, Beth A. Polidoro, T. Brooks, Kent E. Carpenter, G. J. Edgar, S Henderson, J. Sanciangco, D. R. Robertson Jan 2012

Patterns Of Extinction Risk And Threat For Marine Vertebrates And Habitat-Forming Species In The Tropical Eastern Pacific, Beth A. Polidoro, T. Brooks, Kent E. Carpenter, G. J. Edgar, S Henderson, J. Sanciangco, D. R. Robertson

Biological Sciences Faculty Publications

Marine conservation activities around the globe are largely undertaken in the absence of comprehensive species-specific information. To address this gap, complete regional species assemblages of major marine taxa are being progressively assessed against the Categories and Criteria of the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. The present study is the first analysis of entire major components of the biota of a large marine biogeographic region conducted in the Tropical Eastern Pacific (TEP). It is based on recently completed IUCN Red List assessments for all known species of bony and cartilaginous shorefishes, corals, mangroves, …


Protandric Simultaneous Hermaphroditism In Parhippolyte Misticia (Clark, 1989) (Caridea: Hippolytidae): Implications For The Evolution Of Mixed Sexual Systems In Shrimp, Hitoshi Onaga, G. Curt Fiedler, J. Antonio Baeza Jan 2012

Protandric Simultaneous Hermaphroditism In Parhippolyte Misticia (Clark, 1989) (Caridea: Hippolytidae): Implications For The Evolution Of Mixed Sexual Systems In Shrimp, Hitoshi Onaga, G. Curt Fiedler, J. Antonio Baeza

Biological Sciences Faculty Publications

The sexual system of the shrimp Parhippolyte misticia (Clark, 1989), inhabiting the rocky subtidal at Okinawa, Japan and Kimbe Bay, Papua New Guinea, was examined. Dissections suggested that the population consisted of male phase (MP) and functional simultaneous euhermaphrodite (EH) individuals. MPs have cincinulli and appendices masculinae on the first and second pair of pleopods, respectively, gonopores located at the coxae of the third pair of walking legs, and ovotestes with a well-developed male portion containing sperm, but an undeveloped female portion. EHs lacked appendices masculinae and cincinulli. However, they have male gonopores and ovotestes with well-developed ovaries containing mature …


Expansion Dating: Calibrating Molecular Clocks In Marine Species From Expansions Onto The Sunda Shelf Following The Last Glacial Maximum, Eric D. Crandall, Elizabeth J. Sbrocco, Timery S. Deboer, Paul H. Barber, Kent E. Carpenter Jan 2012

Expansion Dating: Calibrating Molecular Clocks In Marine Species From Expansions Onto The Sunda Shelf Following The Last Glacial Maximum, Eric D. Crandall, Elizabeth J. Sbrocco, Timery S. Deboer, Paul H. Barber, Kent E. Carpenter

Biological Sciences Faculty Publications

The rate of change in DNA is an important parameter for understanding molecular evolution and hence for inferences drawn from studies of phylogeography and phylogenetics. Most rate calibrations for mitochondrial coding regions in marine species have been made from divergence dating for fossils and vicariant events older than 1-2 My and are typically 0.5-2% per lineage per million years. Recently, calibrations made with ancient DNA (aDNA) from younger dates have yielded faster rates, suggesting that estimates of the molecular rate of change depend on the time of calibration, decaying from the instantaneous mutation rate to the phylogenetic substitution rate. aDNA …


Marine Invertebrate Life, Rachael Kemp, Howard Peters, Louise Allcock, Kent Carpenter, David Obura, Beth Polidoro, Nadia Richman Jan 2012

Marine Invertebrate Life, Rachael Kemp, Howard Peters, Louise Allcock, Kent Carpenter, David Obura, Beth Polidoro, Nadia Richman

Biological Sciences Faculty Publications

Marine invertebrates are key components of all marine ecosystems, and play critical roles in essential ecological processes, food provision for humans, and diverse and productive food webs. Despite their importance, the vast majority of marine invertebrates are very poorly known. Research has tended to focus on the larger, more conspicuous and economically important species. Humans have long exploited the margins of pelagic ecosystems, but over the past five decades, rapid technological advancement has allowed more routine access to deeper waters [1]. Increasing exploration into the oceans that cover 70% of the world's surface has led to rapid advancement of species …


Extinction Risk And Bottlenecks In The Conservation Of Charismatic Marine Species, Loren Mcclenachan, Andrew B. Cooper, Kent E. Carpenter, Nicholas K. Dulvy Jan 2012

Extinction Risk And Bottlenecks In The Conservation Of Charismatic Marine Species, Loren Mcclenachan, Andrew B. Cooper, Kent E. Carpenter, Nicholas K. Dulvy

Biological Sciences Faculty Publications

The oceans face a biodiversity crisis, but the degree and scale of extinction risk remains poorly characterized. Charismatic species are most likely to gar- ner greatest support for conservation and thus provide a best-case scenario of the status of marine biodiversity. We summarize extinction risk and diagnose impediments to successful conservation for 1,568 species in 16 families of marine animals in the movie Finding Nemo. Sixteen percent (12–34%) of those that have been evaluated are threatened, ranging from 9% (7–28%) of bony fishes to 100% (83–100%) of marine turtles. A lack of scientific knowledge impedes analysis of threat status …


Four Events Of Host Switching In Aspidoderidae (Nematoda) Involve Convergent Lineages Of Mammals, F. Agustín Jiménez-Ruiz, Scott Lyell Gardner, Graciela Navone, Guillermo Ortí Jan 2012

Four Events Of Host Switching In Aspidoderidae (Nematoda) Involve Convergent Lineages Of Mammals, F. Agustín Jiménez-Ruiz, Scott Lyell Gardner, Graciela Navone, Guillermo Ortí

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The Great American Interchange resulted in the mixing of faunistic groups with different origins and evolutionary trajectories that underwent rapid diversification in North and South America. As a result, groups of animals of recent arrival converged into similar habits and formed ecological guilds with some of the endemics. We present a reconstruction of the evolutionary events in Aspidoderidae, a family of nematodes that infect mammals that are part of this interchange, i.e., dasypodids, opossums, and sigmodontine, geomyid, and hystricognath rodents. By treating hosts as discrete states of character and using parsimony and Bayesian inferences to optimize these traits into the …


Leptodactylus Pentadactylus, Miriam M. Heyer, W. R. Heyer, Rafael O. De Sá Jan 2012

Leptodactylus Pentadactylus, Miriam M. Heyer, W. R. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus pentadactylus (Figure 1) are large, the head is about as wide as long, and the hind limbs are moderately long (Table 1; Heyer and Thompson [2000] provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are not visible externally or are moderately expanded as a single sac. Sexually active males usually do not have hypertrophied forearms (the largest male examined, 195 mm SVL, has very weakly hypertrophied forearms), only the largest males have a single small to moderate size black spine on each thumb. No males have chest spines. Dorsolateral folds are …


Evolution And The Expression Of Biases: Situational Value Changes The Endowment Effect In Chimpanzees, Owen D. Jones, Sarah F. Brosnan, Molly Gardner, Susan P. Lambeth, Steven J. Schapiro Jan 2012

Evolution And The Expression Of Biases: Situational Value Changes The Endowment Effect In Chimpanzees, Owen D. Jones, Sarah F. Brosnan, Molly Gardner, Susan P. Lambeth, Steven J. Schapiro

Vanderbilt Law School Faculty Publications

Cognitive and behavioral biases, which are widespread among humans, have recently been demonstrated in other primates, suggesting a common origin. Here we examine whether the expression of one shared bias, the endowment effect, varies as a function of context. We tested whether objects lacking inherent value elicited a stronger endowment effect (or preference for keeping the object) in a context in which the objects had immediate instrumental value for obtaining valuable resources (food). Chimpanzee subjects had opportunities to trade tools when food was not present, visible but unobtainable, and obtainable using the tools. We found that the endowment effect for …


Biophysics, Environmental Stochasticity, And The Evolution Of Thermal Safety Margins In Intertidal Limpets, W. Wesley Dowd, M. W. Denny Jan 2012

Biophysics, Environmental Stochasticity, And The Evolution Of Thermal Safety Margins In Intertidal Limpets, W. Wesley Dowd, M. W. Denny

Biology Faculty Works

As the air temperature of the Earth rises, ecological relationships within a community might shift, in part due to differences in the thermal physiology of species. Prediction of these shifts – an urgent task for ecologists – will be complicated if thermal tolerance itself can rapidly evolve. Here, we employ a mechanistic approach to predict the potential for rapid evolution of thermal tolerance in the intertidal limpet Lottia gigantea. Using biophysical principles to predict body temperature as a function of the state of the environment, and an environmental bootstrap procedure to predict how the environment fluctuates through time, we create …


Nitrogen Deposition Effects On Production And Decomposition Of Coarse Woody Debris, Bethany Jeanne Lyons Jan 2012

Nitrogen Deposition Effects On Production And Decomposition Of Coarse Woody Debris, Bethany Jeanne Lyons

Dissertations, Master's Theses and Master's Reports - Open

Atmospheric nitrogen deposition has the potential to impact forest productivity, microbial associations, nutrient cycling, decomposition and stand dynamics. However, among the least studied aspects of these processes are the production and decomposition of dead woody biomass, or coarse woody debris (CWD). Coarse woody debris is made up of dead woody material on the ground called down dead wood (DDW) and dead standing trees which are often referred to as snags. Observed reductions in decomposition of CWD have been linked to substrate quality and microbial communities. If the decomposition effect is ubiquitous among litter types, CWD density, C:N, and biomass are …


Chapter 4 - Aquaria, Janice M. Glime Jan 2012

Chapter 4 - Aquaria, Janice M. Glime

Bryophyte Ecology Volume 5: Uses

Explore the contents of Bryophyte Ecology, Volume 5, Chapter 4 - Aquaria by clicking the link above. For the Contents section of this ebook, as well as Volumes 1 through 5, please visit the Bryophyte Ecology Main Page.

Use CTRL+F to easily search within PDF files.

Ebook sponsored by Michigan Technological University and the International Association of Bryologists.


Influences Of Adjacent Land-Use On Avian Community Structure In Sub-Boreal Peatlands Of The Midwest, Lucas J. Wandrie Jan 2012

Influences Of Adjacent Land-Use On Avian Community Structure In Sub-Boreal Peatlands Of The Midwest, Lucas J. Wandrie

All Graduate Theses, Dissertations, and Other Capstone Projects

Surrounding land use influences avian community structure; moreover, anthropogenic manipulation of habitat can alter bird species richness and composition. In the first chapter of my thesis work, I conducted avian surveys at 20 sub-boreal peatlands in eastern Minnesota and western Wisconsin to detect correlations between land development and bird community structure. Peatlands are wetlands that accumulate decaying organic plant material (peat) and provide valuable and diverse habitats to a variety of flora and fauna. I measured urban and cropland development at three spatial scales (500 m, 1000 m, and 2500 m radii). Effects of development on avian communities also were …


A Meta-Analysis Of Seaweed Impacts On Seagrasses: Generalities And Knowledge Gaps, Mads Thomsen, Thomas Wernberg, Aschwin H. Engelen, Fernando Tuya, Mat A. Vanderklift, Marianne Holmer, Karen J. Mcglathery, Francisco Arenas, Jonne Kotta, Brian R. Silliman Jan 2012

A Meta-Analysis Of Seaweed Impacts On Seagrasses: Generalities And Knowledge Gaps, Mads Thomsen, Thomas Wernberg, Aschwin H. Engelen, Fernando Tuya, Mat A. Vanderklift, Marianne Holmer, Karen J. Mcglathery, Francisco Arenas, Jonne Kotta, Brian R. Silliman

Research outputs 2012

Seagrasses are important habitat-formers and ecosystem engineers that are under threat from bloom-forming seaweeds. These seaweeds have been suggested to outcompete the seagrasses, particularly when facilitated by eutrophication, causing regime shifts where green meadows and clear waters are replaced with unstable sediments, turbid waters, hypoxia, and poor habitat conditions for fishes and invertebrates. Understanding the situations under which seaweeds impact seagrasses on local patch scales can help proactive management and prevent losses at greater scales. Here, we provide a quantitative review of available published manipulative experiments (all conducted at the patch-scale), to test which attributes of seaweeds and seagrasses (e.g., …


On The Global Stability Of A Generalized Cholera Epidemiological Model, Yuanji Cheng, Jin Wang, Xiuxiang Yang Jan 2012

On The Global Stability Of A Generalized Cholera Epidemiological Model, Yuanji Cheng, Jin Wang, Xiuxiang Yang

Mathematics & Statistics Faculty Publications

In this paper, we conduct a careful global stability analysis for a generalized cholera epidemiological model originally proposed in [J. Wang and S. Liao, A generalized cholera model and epidemic/endemic analysis, J. Biol. Dyn. 6 (2012), pp. 568-589]. Cholera is a water-and food-borne infectious disease whose dynamics are complicated by the multiple interactions between the human host, the pathogen, and the environment. Using the geometric approach, we rigorously prove the endemic global stability for the cholera model in three-dimensional (when the pathogen component is a scalar) and four-dimensional (when the pathogen component is a vector) systems. This work unifies the …


Novel Lineages Of Prochlorococcus And Synechococcus In The Global Oceans, Sijun Huang, Steven W. Wilhelm, H. Rodger Harvey, Karen Taylor, Nianzhi Jiao, Feng Chen Jan 2012

Novel Lineages Of Prochlorococcus And Synechococcus In The Global Oceans, Sijun Huang, Steven W. Wilhelm, H. Rodger Harvey, Karen Taylor, Nianzhi Jiao, Feng Chen

OES Faculty Publications

Picocyanobacteria represented by Prochlorococcus and Synechococcus have an important role in oceanic carbon fixation and nutrient cycling. In this study, we compared the community composition of picocyanobacteria from diverse marine ecosystems ranging from estuary to open oceans, tropical to polar oceans and surface to deep water, based on the sequences of 16S-23S rRNA internal transcribed spacer (ITS). A total of 1339 ITS sequences recovered from 20 samples unveiled diverse and several previously unknown clades of Prochlorococcus and Synechococcus. Six high-light (HL)-adapted Prochlorococcus clades were identified, among which clade HLVI had not been described previously. Prochlorococcus clades HLIII, HLIV and …


Diversity, Distribution, And Expression Of Diazotroph Nifh Genes In Oxygen-Deficient Waters Of The Arabian Sea, Amal Jayakumar, Mamoon M. D. Al-Rshadat, Bess B. Ward, Margaret R. Mulholland Jan 2012

Diversity, Distribution, And Expression Of Diazotroph Nifh Genes In Oxygen-Deficient Waters Of The Arabian Sea, Amal Jayakumar, Mamoon M. D. Al-Rshadat, Bess B. Ward, Margaret R. Mulholland

OES Faculty Publications

The Arabian Sea oxygen minimum zone (OMZ), the largest suboxic region in the world's oceans, is responsible for up to half of the global mesopelagic fixed nitrogen ( N ) loss from the ocean via denitrification and anammox. Dinitrogen (N2) fixation is usually attributed to cyanobacteria in the surface ocean. Model prediction and physiological inhibition of N2 fixation by oxygen, however, suggest that N2 fixation should be enhanced near the oxygen-deficient zone (ODZ) of the Arabian Sea. N2 fixation and cyanobacterial nifH genes (the gene encoding dinitrogenase reductase) have been reported in surface waters overlying …


Development Of High-Yielding Sweetgum Plantation Systems For Bioenergy Production In The Southeastern United States, Donald J. Kaczmarek, Brian C. Wachelka, Jeff Wright, Victor C. Steel, Doug P. Aubrey, David R. Coyle, Mark D. Coleman Jan 2012

Development Of High-Yielding Sweetgum Plantation Systems For Bioenergy Production In The Southeastern United States, Donald J. Kaczmarek, Brian C. Wachelka, Jeff Wright, Victor C. Steel, Doug P. Aubrey, David R. Coyle, Mark D. Coleman

Biology: Faculty Presentations

No abstract provided.


Recent Changes In The Growth And Nutrient Limitation Of Benthic And Pelagic Algae In Arctic Tundra Ponds, Christina Hernandez Jan 2012

Recent Changes In The Growth And Nutrient Limitation Of Benthic And Pelagic Algae In Arctic Tundra Ponds, Christina Hernandez

Open Access Theses & Dissertations

Arctic ponds are a dominant feature in Barrow, Alaska. Ponds may function as carbon sinks during the growing season from production of photosynthetic organisms like algae; however, little work has been done on this topic. Environmental changes have been occurring in the Arctic stemming from climate change and human perturbations. The focus of this study was to assess a historically studied region for changes in algal primary production that may have been produced due to increases in temperature over the past 40 years and increased human development. Additionally, this study aimed to determine nutrient limitation of algal production in the …


Implications Of Decade Time Scale Arctic Plant Community Change On Ecosystem Function, Mark Jason Lara Jan 2012

Implications Of Decade Time Scale Arctic Plant Community Change On Ecosystem Function, Mark Jason Lara

Open Access Theses & Dissertations

Almost half the global soil organic carbon pool is found in northern high latitudes. The majority of this soil carbon is stored in a greenhouse inert state within permafrost. As pronounced warming of high northern latitudes ensues, there is a strong likelihood that this substantial soil organic carbon pool will be mobilized to the atmosphere where it is likely to positively enhance greenhouse warming. Modeling studies suggest this positive feedback could alter future climate states of the Arctic and the globe, and affect how humans may need to adapt to climate change. Accordingly, understanding the patterns and controls and the …


Recipes Of Resolve: Food And Meaning In Post-Diluvian New Orleans, Jessica Claire Menck Jan 2012

Recipes Of Resolve: Food And Meaning In Post-Diluvian New Orleans, Jessica Claire Menck

Antioch University Dissertations & Theses

In 2005 the city of New Orleans experienced catastrophic flooding as a result of the failure of the federal levee system following Hurricane Katrina. This was an immediate disaster that evolved into a longer-term crisis as the city, state, and national government struggled to respond to the event. This study focuses on one part of managing crisis: meaning making. Specifically, the study investigates meaning making within the food community of New Orleans, asking the questions: is food a way for individuals and groups to make meaning following critical change events such as the failure of the federal levee system in …


Systematics Of Leptopelis (Anura: Arthroleptidae) From The Itombwe Plateau, Eastern Democratic Republic Of The Congo, Francisco Portillo Jan 2012

Systematics Of Leptopelis (Anura: Arthroleptidae) From The Itombwe Plateau, Eastern Democratic Republic Of The Congo, Francisco Portillo

Open Access Theses & Dissertations

Leptopelis, a genus of Central African treefrogs, includes 51 species that live in tropical forests and savannas. Currently, only two species of Leptopelis are known from the poorly explored Itombwe Plateau in eastern Democratic Republic of the Congo (DRC). Itombwe is renowned among conservationists for its rich and endemic amphibian fauna, including: Xenopus itombwensis, Chrysobatrachus cupreonitens, Laurentophryne parkeri, Hyperolius leleupi and at least three species of Arthroleptis. Evolutionary relationships of Itombwe Leptopelis were examined by sequencing two mitochondrial genes (16S: 557 bp [base pairs], cyt b: 620 bp) and one nuclear gene (RAG1: 761 bp). Results recovered strong support for …


The Impact Of Decadal Land Cover Change On The Global Warming Potential Of Beringian Arctic Tundra, David Hwei-Len Lin Jan 2012

The Impact Of Decadal Land Cover Change On The Global Warming Potential Of Beringian Arctic Tundra, David Hwei-Len Lin

Open Access Theses & Dissertations

Arctic terrestrial ecosystems play an important role in the global carbon cycle. If arctic warming continues to rise as projected, large amounts of soil carbon stored in these ecosystems could be released to the atmosphere as carbon dioxide or methane and positively enhance greenhouse warming. Thus, improving understanding of the likely future state and fate of arctic soil carbon, and the carbon uptake potential of arctic terrestrial ecosystems are well recognized research priorities.

At the pan-arctic scale, decadal increases in NDVI (Normalized Difference Vegetation Index), an index of vegetation productivity, have been observed from satellite imagery, indicating a general greening …


Spatial Ecology Of The Trans-Pecos Rat Snake (Bogertophis Subocularis) In The Chihuahuan Desert Of Trans-Pecos Texas, Arturo Rocha Jan 2012

Spatial Ecology Of The Trans-Pecos Rat Snake (Bogertophis Subocularis) In The Chihuahuan Desert Of Trans-Pecos Texas, Arturo Rocha

Open Access Theses & Dissertations

The Trans-Pecos Rat Snake (Bogertophis subocularis) is a medium to large rat snake that occurs from south-central New Mexico, south-central Texas, down into the north-central and northeastern states of Mexico. There is paucity in the ecology of B. subocularis to date. Some North American colubrid snakes, such as Thamnophis sirtalis, are the most represented species in thermal ecology and life history studies in all reptiles. There is nothing known on the winter ecological aspects of this species, and very little information regarding its overall ecology. The goal of this study is to determine home range, movement patterns, habitats and utilization …


An Assessment Of Land Cover Change At The Indio Mountains Research Station, Rebecca Anne Escamilla Jan 2012

An Assessment Of Land Cover Change At The Indio Mountains Research Station, Rebecca Anne Escamilla

Open Access Theses & Dissertations

Land cover change is a significant contributor to environmental change on a global scale. In the arid regions of the southwest US, shrub encroachment is one of the most important forms of land cover change. Many factors contribute to shrub encroachment, which can impact structure and function. In the Chihuahuan Desert, mountain ecosystems are known as biodiversity hotspots and are especially susceptible to environmental change making them useful indicators of global change. The overarching goal of this dissertation is to improve i) understanding of land cover change in a Chihuahuan Desert mountain landscape, and ii) how knowledge of land cover …