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 11611 - 11640 of 19729

Full-Text Articles in Entire DC Network

Effects Of Human Recreational Activity On The Tameness Of Common Loons (Gavia Immer) In Northern Wisconsin, Seth Yund May 2015

Effects Of Human Recreational Activity On The Tameness Of Common Loons (Gavia Immer) In Northern Wisconsin, Seth Yund

Student Scholar Symposium Abstracts and Posters

The Common Loon (Gavia immer) is an aquatic diving bird that lives in freshwater habitats in Canada and the northern U.S.. Human activity on a loon’s resident lake may affect its fitness and behavior, yet few studies identify or quantify these effects. We modified existing techniques that measure escape distances in other species to measure tameness as the distance at which individual loons dove in response to human approach by canoe. Tameness was similar between pair members, suggesting that common lake conditions or the behavior of a mate might influence the behavior. Sex, size within sex, and human activity did …


Effects Of El Niño On Ecological Growth Along Californian And Peruvian Coasts, Alexandra Sidun May 2015

Effects Of El Niño On Ecological Growth Along Californian And Peruvian Coasts, Alexandra Sidun

Student Scholar Symposium Abstracts and Posters

This study examines the mechanisms of El Niño to further understand the ecological effects it may have along the Californian and Peruvian coasts. El Niño is the warm phase of the El Niño Southern Oscillation (ENSO). While it is a global phenomenon, these two locations were investigated for their nearly equal and opposite conditions during storm months. California, which is in an extreme state of drought, often receives heavy rainfall during El Niño and understanding its potential effects is crucial. El Niño causes upwellings along the CA coast and warm water from the region displaces the normally cool waters along …


Possible Precursor Events To Earthquakes And The Resulting Effects On Organic Material In The Surrounding Water Bodies, Kiyoko Nakatsui May 2015

Possible Precursor Events To Earthquakes And The Resulting Effects On Organic Material In The Surrounding Water Bodies, Kiyoko Nakatsui

Student Scholar Symposium Abstracts and Posters

Being located on the “Ring of Fire” Japan experiences many seismic events. Adding to this, it is located at the convergence of four fault lines where seismic activity will be even more frequent and severe. Although small tremors occurring in an area are indicators of an earthquake to come it only gives minutes of warning. Scientists are now trying to see if latent heat and gas release from fault lines can indicate an earthquake to come with hours or even days of warning. MODIS aqua and terra data will be analyzed in order to see if such precursors can be …


Puffs And Tufts: A Comparison Of Trichodesmium Colony Formations And Nutrient Availability Across The North Atlantic Ocean Using Remote Sensing Methods, Marc Rosenfield May 2015

Puffs And Tufts: A Comparison Of Trichodesmium Colony Formations And Nutrient Availability Across The North Atlantic Ocean Using Remote Sensing Methods, Marc Rosenfield

Student Scholar Symposium Abstracts and Posters

Trichodesmium, a genus of diazotrophic bacteria, has the capability and the population to produce a large percentage of the total oceanic N2-fixation. Though their population is known to be heavily dependent on two of the ocean’s largest limiting factors, phosphorus and iron concentrations, it is unknown what affect these factors have on the population. In this study two of the largest colony formations of Trichodesmium in the North Atlantic, tufts and puffs, are compared nutrient quality with respect to time and geographical location. Though very little nutrient in situ data was collected from the cruise, remote sensing data collected from …


Evaluation Of Temperature Anomalies And Ocean Productivity During The 2004 Sumatra-Andaman Earthquake, Cora Byers, Brenna Mcnabb May 2015

Evaluation Of Temperature Anomalies And Ocean Productivity During The 2004 Sumatra-Andaman Earthquake, Cora Byers, Brenna Mcnabb

Student Scholar Symposium Abstracts and Posters

The oceanic productivity of the Indian Ocean and temperature anomalies prior to the Sumatra-Andaman earthquake (MW =9.3) and tsunami (December 26th 2004) were studied. Data was obtained via NASA’s Giovanni program to determine the effect on phytoplankton (primary producers) and temperature changes over the region of the earthquake. Seasonal trends were visible in the concentrations of chlorophyll a, coccolithophores, cyanobacteria, chlorophytes, diatoms and absorption coefficient, in addition to storm trends.


Biological Degradation Of Acetaldehyde In Southern California Coastal Waters, Mary Senstad, Sovanndara Hok, Ori Barashy, Catherine D. Clark, Warren J. De Bruyn May 2015

Biological Degradation Of Acetaldehyde In Southern California Coastal Waters, Mary Senstad, Sovanndara Hok, Ori Barashy, Catherine D. Clark, Warren J. De Bruyn

Student Scholar Symposium Abstracts and Posters

Oxygenated hydrocarbons are ubiquitous in the atmosphere with levels ranging from low ppt (acetaldehyde) to low ppb (methanol). As an OH sink and an atmospheric HOx and ozone source, oxygenated hydrocarbons have a direct impact on the oxidative capacity of the atmosphere. The oceans are one of the largest sources of uncertainty in current atmospheric budget estimates of these species. A better understanding of the processes that produce and destroy these species in seawater would improve our understanding of the role of the oceans in cycling these species into or out of the atmosphere. We have measured the degradation rate …


Effects Of Ecologically Realistic Heating Profiles On Feeding In The Intertidal Hermit Crab, Pagurus Sameulis, Paige Davis May 2015

Effects Of Ecologically Realistic Heating Profiles On Feeding In The Intertidal Hermit Crab, Pagurus Sameulis, Paige Davis

Student Scholar Symposium Abstracts and Posters

The intertidal zone is an ideal habitat to investigate effects of global warming because species living in it are very close to their physiological limits. Initial studies of invertebrate physiological responses to heat stress have employed relatively abrupt increases in temperature. My research investigates effects of ecologically more realistic temperature profiles on feeding in the intertidal hermit crab, Pagurus sameulis. Recent work in the Wright lab showed that feeding in this species is inhibited by an abrupt increase in temperature. Because temperature change in the natural environment of Pagurus is much more gradual, I hypothesize that such a gradual temperature …


Assessing Water Quality In The Gulf Of Mexico Using Remote Sensing Data., Alliyah Thomas May 2015

Assessing Water Quality In The Gulf Of Mexico Using Remote Sensing Data., Alliyah Thomas

Student Scholar Symposium Abstracts and Posters

Hypoxia, or oxygen depletion, is a process that occurs in conjunction with eutrophication. In hypoxic conditions the dissolved oxygen levels in the water column sink to unlivable conditions for the marine organisms causing them to flee or die. Despite efforts of improvement, the annual summer Gulf of Mexico dead zone continues to be a serious threat to aquatic ecosystems. The 2012 smaller than usual dead zone was a false indicator of future improvement. The 2012 dead zone decrease was connected to the drought and inability of large amounts of runoff to flow into the gulf. Water quality analysis was done …


Social Communication Of Predator-Induced Changes In Drosophila Behavior And Germ Line Physiology, Balint Z. Kacsoh, Julianna Bozler, Mani Ramaswami, Giovanni Bosco May 2015

Social Communication Of Predator-Induced Changes In Drosophila Behavior And Germ Line Physiology, Balint Z. Kacsoh, Julianna Bozler, Mani Ramaswami, Giovanni Bosco

Dartmouth Scholarship

Behavioral adaptation to environmental threats and subsequent social transmission of adaptive behavior has evolutionary implications. In Drosophila, exposure to parasitoid wasps leads to a sharp decline in oviposition. We show that exposure to predator elicits both an acute and learned oviposition depression, mediated through the visual system. However, long-term persistence of oviposition depression after predator removal requires neuronal signaling functions, a functional mushroom body, and neurally driven apoptosis of oocytes through effector caspases. Strikingly, wasp-exposed flies (teachers) can transmit egg-retention behavior and trigger ovarian apoptosis in naive, unexposed flies (students). Acquisition and behavioral execution of this socially learned behavior …


Variation In Trembling Aspen And White Spruce Wood Quality Grown In Mixed And Single Species Stands In The Boreal Mixedwood Forest, Francis De Araujo, James F. Hart, Shawn D. Mansfield May 2015

Variation In Trembling Aspen And White Spruce Wood Quality Grown In Mixed And Single Species Stands In The Boreal Mixedwood Forest, Francis De Araujo, James F. Hart, Shawn D. Mansfield

Aspen Bibliography

The Canadian boreal forest is largely represented by mixed wood forests of white spruce (Picea glauca (Moench) Voss) and trembling aspen (Populus tremuloides Michx). In this study, a total of 300 trees originating from three sites composed of trembling aspen and white spruce with varying compositions were investigated for wood quality traits: one site was composed mainly of aspen, one mainly of spruce and a third was a mixed site. Four wood quality traits were examined: wood density, microfibril angle (MFA), fibre characteristics, and cell wall chemistry. Social classes were also determined for each site in an attempt …


Comparing Pseudo-Environmental And Horizontal Plus Pseudo-Environmental Transmission Of A Probiotic Janithinobacterium Lividum Between Green Frog Tadpoles, Stephen Simonetti May 2015

Comparing Pseudo-Environmental And Horizontal Plus Pseudo-Environmental Transmission Of A Probiotic Janithinobacterium Lividum Between Green Frog Tadpoles, Stephen Simonetti

Senior Honors Projects, 2010-2019

The gram-negative bacteria, Janthinobacterium lividum (J.liv) is able to kill the pathogenic fungus known as Batrachochytrium dendrobatidis (Bd), which is known to be causing massive amphibian decline worldwide. The purpose of this research was to identify the ability of the probiotic bacteria, Janthinobacterium lividum (J.liv), to be horizontally transmitted from individual to individual and/or pseudo-environmentally transmitted from individual to environment and back to individual between Lithobates clamitans (green frog) tadpoles. Based on previous findings I hypothesized that pseudo-environmental and horizontal transmission will occur in tadpoles. This would be important for helping stop the decline of amphibians because it would provide …


Comparative Analysis Of Anti-Bd Bacteria From Six Malagasy Frog Species Of Ranomafana National Park, Kelsey Savage May 2015

Comparative Analysis Of Anti-Bd Bacteria From Six Malagasy Frog Species Of Ranomafana National Park, Kelsey Savage

Senior Honors Projects, 2010-2019

As Malagasy amphibians are facing an impending extinction crisis from the lethal skin fungus Batrachochytrium dendrobatidis (Bd), it has become imperative to proactively mitigate the threat. Bd sporangia develop in the skin of infected amphibians and cause the skin to thicken, leading to ionic imbalance and eventual heart failure. It has been shown that certain bacterial species are able to inhibit Bd growth on amphibians by producing antifungal metabolites. Community-based probiotics are one approach used to combat chytridomycosis by inoculating an environment with Bd-inhibitory bacteria so that many amphibian species are treated at once. With this method, it is important …


Experimental Greenhouse And Field Trials On American Ginseng, Panax Quinquefolium: Implications For Restoration In Appalachia, Emily Thyroff May 2015

Experimental Greenhouse And Field Trials On American Ginseng, Panax Quinquefolium: Implications For Restoration In Appalachia, Emily Thyroff

Senior Honors Projects, 2010-2019

Panax quinquefolium, American ginseng, is one of the more valuable non-timber forest products, NTFPs, providing economic, cultural, and ecological ecosystem services in forests. Although ginseng has a broad distribution range, it is not abundant anywhere due to overharvesting and deer browse. This study included experimental field and greenhouse trials to determine optimal growing conditions given inconsistencies regarding aspect and soil. Three soil series and two aspects (represented by soil moisture in the greenhouse) were manipulated in a factorial design. We hypothesized that there would be significant differences in ginseng performance (germination, survival, leaf area, and height) due to soil and …


Insomniac Of The Soil: A Collection Of Poetry And Essays, Sarah E. Golibart May 2015

Insomniac Of The Soil: A Collection Of Poetry And Essays, Sarah E. Golibart

Senior Honors Projects, 2010-2019

“Insomniac of the Soil” is a homage to a landscape that has deeply informed Sarah Golibart's life and her artistic voice – the tidewater flatlands of Virginia’s Chesapeake Bay peninsula where her family lives and where Golibart has worked on farms since high school. Both her poems and essays are earthy, imagistic, and grounded – quite literally – in the soil as well as in a sensibility of ecological ethics and sustainability. “Insomniac of the Soil” is also a love song to the fervent and fallow cycles of the soil.


Fishing For A Sustainable Future: Aquaponics As A Method Of Food Production, Richard Ramsundar May 2015

Fishing For A Sustainable Future: Aquaponics As A Method Of Food Production, Richard Ramsundar

Student Theses 2015-Present

This thesis compares and explains the advantages aquaponics farming has over modern industrial intensive farming. Through a comparison natural capital usage, conservation, recycling and cost, the thesis advocates for the expansion of aquaponics usage in urban settings. The thesis also explains the history of intensive farming and aquaponics in America, the science of how aquaponics operates, the economic and environmental costs of modern intensive farming versus aquaponics farming, and the social implications of aquaponics. Lastly, I propose a policy that reallocates farm subsidies by modifying the Farm Bill. Then I propose policies that support creating a new standard of farm …


Distributional Expansion Of The Hispid Cotton Rat (Sigmodon Hispidus) Into Dawson County, Nebraska, Jennifer D. Frisch, Keith Geluso, Joseph T. Springer May 2015

Distributional Expansion Of The Hispid Cotton Rat (Sigmodon Hispidus) Into Dawson County, Nebraska, Jennifer D. Frisch, Keith Geluso, Joseph T. Springer

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

In the last century, the Hispid Cotton Rat (Sigmodon hispidus) has moved northward in central parts of the United States, reaching Nebraska in the late 1950s. Recent surveys demonstrate Hispid Cotton Rats inhabit counties across southern parts of Nebraska south of the Platte River. Herein, we report on captures of S. hispidus from a new county (Dawson County), its seasonal occurrence at our study site, and the first known record of the Hispid Cotton Rat north of channels of the Platte River. Our captures represent one of the northern-most records in Nebraska.


The Effect Of Controlled Burns On Abundance Of Woody Species At Buck Mountain, West Virginia, Barry E. Edgar May 2015

The Effect Of Controlled Burns On Abundance Of Woody Species At Buck Mountain, West Virginia, Barry E. Edgar

Masters Theses, 2010-2019

Each year, the U.S. Forest Service prescribes burns within the George Washington and Jefferson National Forest (GWJNF). Burns are prescribed in the growing (late April-October) and dormant season (November- mid-April). The goal of the burns is to reinstate the natural fire regime, returning forests to their original species composition. Currently in GWJNF, Appalachian pine-oak forests are experiencing an increase in fire-intolerant species, while Quercus species and Gaylussacia brachycera, an endangered shrub species, are declining. In the summer of 2014, a vegetation survey was conducted on Buck Mountain, West Virginia to determine if there was a significant difference between dormant and …


Using Capture-Mark-Recapture Techniques To Estimate Detection Probabilities & Fidelity Of Expression For The Critically Endangered James Spinymussel (Pleurobema Collina)., Alaina C. Esposito May 2015

Using Capture-Mark-Recapture Techniques To Estimate Detection Probabilities & Fidelity Of Expression For The Critically Endangered James Spinymussel (Pleurobema Collina)., Alaina C. Esposito

Masters Theses, 2010-2019

The critically endangered James Spinymussel (Pleurobema collina) is a species of freshwater mussel endemic to Virginia’s James and Dan River basins. In the last 20 years, P. collina has experienced a substantial decline in numbers and currently occupies approximately 10% of its original habitat; however, little information is known about this species to assist in conservation. A 230-meter reach of transitional habitat in Swift Run was selected for repeat observations to estimate detection probabilities using a Capture-Mark-Recapture framework. In June 2014, visual scouting began to locate and tag P. collina (including other mussels in the community) with PIT …


Teaching Evolution: A Students’ Perspective, Abdullah Allaoa, Tyniqua Hinton May 2015

Teaching Evolution: A Students’ Perspective, Abdullah Allaoa, Tyniqua Hinton

Publications and Research

Many may wonder “where do we come from?” Over time, scientists have pondered and tested the concept of evolution. Simply put, evolution is gradual change over time. A major tenet of evolution is natural selection, which includes three principles which are variation in population, differential reproduction due to competition, and heredity. These principles are supported by multiple lines of evidence, including biochemical, geographical, fossil, and anatomical evidence. By providing tangible, real-world examples of evolution, we hope to provide a clear understanding of this long-studied scientific breakthrough, while at the same time showing how animals (including us) are related to each …


Divergence Of Vertebrate And Insect Specific Toxin Genes Between Three Species Of Widow Spider, Shannon G. Kahn May 2015

Divergence Of Vertebrate And Insect Specific Toxin Genes Between Three Species Of Widow Spider, Shannon G. Kahn

Honors College Theses

The Brown widow spider, Latrodectus geometricus, is an introduced species to the southern United States (Brown 2008). The Brown widow is a member of the widow spider genus Latrodectus which includes the southern Black widow (L. mactans) and 29 other venomous species. All species of widow spiders produce venom which is used against both predator and prey. These venoms are composed of several different species-specific toxins, each encoded by a different gene (Graudins 2012). Previous research has shown that positive selection pressures affect the venom of snakes and snails, thus aiding in adaptive potential of the species …


Does Reproductive Investment Decrease Telomere Length In Menidia Menidia?, Jin Gao, Stephan B. Munch May 2015

Does Reproductive Investment Decrease Telomere Length In Menidia Menidia?, Jin Gao, Stephan B. Munch

Department of Biomedical Engineering Faculty Publications

Given finite resources, intense investment in one life history trait is expected to reduce investment in others. Although telomere length appears to be strongly tied to age in many taxa, telomere maintenance requires energy. We therefore hypothesize that telomere maintenance may trade off against other life history characters. We used natural variation in laboratory populations of Atlantic silversides (Menidia menidia) to study the relationship between growth, fecundity, life expectancy, and relative telomere length. In keeping with several other studies on fishes, we found no clear dependence of telomere length on age. However, we did find that more fecund …


Effects Of The Developmental Environment On Oxidative Damage And Antioxidants In Red-Eared Slider Turtle ( Trachemys Scripta Elegans ) Hatchlings, Lisa Allison Treidel May 2015

Effects Of The Developmental Environment On Oxidative Damage And Antioxidants In Red-Eared Slider Turtle ( Trachemys Scripta Elegans ) Hatchlings, Lisa Allison Treidel

Theses and Dissertations

Developmental environments influence many individual phenotypes. However, currently we have a limited understanding of how the developmental environment influences oxidative stress resistance phenotypes. Oxidative stress is defined as a physiological state during which the production of harmful free radicals exceeds the protective capabilities of antioxidants. Variations among adults in susceptibility to oxidative stress can have important consequences for life history strategies and fitness related traits. Our work was aimed at providing insight in to the role that the developmental environment plays on oxidative stress phenotypes in the model oviparous reptile the red-eared slider turtle (Trachemys scripta elegans). Here, we conducted …


A Case For An Ecological Approach And Against Language Commodification In Elt, Vinicius O. Souza May 2015

A Case For An Ecological Approach And Against Language Commodification In Elt, Vinicius O. Souza

MA TESOL Collection

This paper aims to provide an alternative approach to the English language education practiced in many developing countries which can help reverse their current low-proficiency status, as revealed by standard international examinations such as the PISA scores and others. The author argues that this can be best accomplished by adopting an ecological approach to teaching which promotes language learning as emergent and socially situated phenomena, two concepts largely neglected by current teaching methods. In fact, many of these countries have long been dominated by an extremely commodified and cognitivist ELT market, where business interests have taken precedence over pedagogical considerations. …


Phylogeography Of Darlingtonea Kentuckensis And Molecular Systematics Of Kentucky Cave Trechines, Olivia Frances Boyd May 2015

Phylogeography Of Darlingtonea Kentuckensis And Molecular Systematics Of Kentucky Cave Trechines, Olivia Frances Boyd

Masters Theses & Specialist Projects

The monotypic cave carabid genus Darlingtonea is widely distributed along the eastern band of the Mississippian/Pennyroyal plateau in Kentucky and northern Tennessee. DNA sequence data from the mitochondrial gene cytochrome oxidase subunit I (COI) was collected from one to four individuals from 27 populations, and patterns of phylogeography and population structure were inferred from COI haplotypes. A hierarchical analysis of molecular variance found low nucleotide diversity within populations and statistically significant variation among geographically-defined groups tested based on two a priori hypotheses of structure. Population structure among five distinct genetic clusters identifies approximate locations of barriers to gene flow among …


Fisheries Management Paper No 274 - Finfish Resources Of The Peel-Harvey Estuary - Harvest Strategy 2015-2020 (Version 1.0), Department Of Fisheries, Western Australia May 2015

Fisheries Management Paper No 274 - Finfish Resources Of The Peel-Harvey Estuary - Harvest Strategy 2015-2020 (Version 1.0), Department Of Fisheries, Western Australia

Fisheries Management Papers

WEST COAST ESTUARINE MANAGED FISHERY (AREA 2)

Harvest strategies for aquatic resources managed by the Western Australian Department of Fisheries (the Department) are formal documents prepared to support the decision-making processes required to ensure the management of these resources are consistent with the principles of Ecologically Sustainable Development (ESD). The objectives of ESD are reflected in the objects of the Fish Resources Management Act 1994 (FRMA), Section 3, and the draft Aquatic Resources Management Bill 2013 (ARMB), Clause 9, which will replace the FRMA once enacted.

The publication of these strategies is intended to make the decision-making considerations and processes …


Herbivore Impacts On The Invasive Marine Alga Grateloupia Turuturu, Emily Bishop, Carol Thornber May 2015

Herbivore Impacts On The Invasive Marine Alga Grateloupia Turuturu, Emily Bishop, Carol Thornber

Senior Honors Projects

Invasive species have the ability to outcompete natives, and can create a monoculture if not mitigated by herbivores or some other mechanism. Limited information exists on the ecology of the invasive macroalga Grateloupia turuturu and how it is impacted by herbivores. Using laboratory mesocosm experiments, we investigated the ability of two invasive herbivore species common in Rhode Island, the snail Littorina littorea and Asian shore crab Hemigrapsus sanguineus, to control Grateloupia populations. In the first trial, Grateloupia was provided to a single herbivore (either Littorina or Hemigrapsus) or both herbivores together. Grateloupia controls were in the same mesocosms …


Rareness Starts Early For Disturbance-Dependent Grassland Plant Species, Matthew Candeias May 2015

Rareness Starts Early For Disturbance-Dependent Grassland Plant Species, Matthew Candeias

Biology Theses

Ecological communities always contain a few common species and an abundance of rare species. Mechanisms determining commonness and rarity require experimental investigation. Given that most plant mortality occurs in seeds and seedlings, recruitment best predicts plant community assemblage and distributions. In northeastern North America, grassland plant species constitute a sizable portion of the native flora. Approximately 30% of western New York’s threatened and endangered flora are associated with grasslands, apparent leftovers from a post-glacial landscape. I investigated the mechanisms behind grassland species commonness and rarity by examining how habitat type, disturbance and biotic interactions limit seed recruitment for three rare …


Forest Sustainability In An Altered Landscape Requires Human Intervention, Adam C. Labatore May 2015

Forest Sustainability In An Altered Landscape Requires Human Intervention, Adam C. Labatore

Biology Theses

Recruitment success determines the abundance and composition of plant communities. Successful recruitment can be summarized as a simple dichotomy of establishment versus seed limitations. Establishment limitation occurs when plant populations are inhibited by habitat availability and quality, whereas seed limitation occurs when seeds fail to arrive in necessary densities. Recruitment failure undermines overstory sustainability if the existing trees cannot replace themselves. Preliminary analysis indicated tree recruitment failure at an urban nature preserve with too few tree seedlings to replace mature canopy trees. These data suggested that the urban forest was not sustainable. The overarching goal of the study was to …


The Evolution Of Body Size In The Order Siluriformes, D Cooper Campbell May 2015

The Evolution Of Body Size In The Order Siluriformes, D Cooper Campbell

Honors Theses

The evolution of body size has long been a topic of interest to biologists due to the close link between size and various aspects of an organism’s biology. Adult body size is influenced by the underlying tradeoff in energy allocation between maintenance, somatic growth and reproduction. I studied the evolution of a large group of globally distributed (primarily freshwater with some marine forms) fishes to test some basic hypotheses about the evolution of adult body size. Catfish (Siluriformes) are an excellent group for this type of research as they represent approximately 11% of fishes and species range in size from …


Management Of A Primordial Problem: Redox-Sensitive Transcriptional Regulation In Methanosarcina Acetivorans, Ryan Christopher Sheehan May 2015

Management Of A Primordial Problem: Redox-Sensitive Transcriptional Regulation In Methanosarcina Acetivorans, Ryan Christopher Sheehan

Graduate Theses and Dissertations

The primordial Earth which hosted the first forms of life was an environment free of oxygen. Early organisms utilized metabolisms dependent upon anaerobic conditions and incorporated systems to which oxygen is deleterious. As the content of oxygen in Earth's atmosphere increased, anaerobic organisms had to acquire methods to sense and combat oxygen and reactive oxygen species. Several mechanisms were advantageous to such anaerobic organisms which correlated transcriptional processes with the redox state of the cell so that energy may be conserved and oxygen stress recovery genes activated during periods of oxidative stress. Iron sulfur (Fe-S) cluster cofactors incorporated within RNA …