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

Life Sciences Commons™

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

Colby College

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 151 - 180 of 3263

Full-Text Articles in Life Sciences

A Postulate For Tiger Recovery: The Case Of The Caspian Tiger, Carlos A. Driscoll, I Chestin, H Jungius, Y Darman, E Dinerstein, J Seidensticker, J Sanderson, S Christie, S J. Luo, M Shrestha, Y Zhuravlev, O Uphyrkina, Y V. Jhala, S P. Yadav, D G. Pikunov, N Yamaguchi, D E. Wildt, J D. Smith, Marker, Philip J. Nyhus, R Tilson, D W. Macdonald, S J. O'Brien Jan 2012

A Postulate For Tiger Recovery: The Case Of The Caspian Tiger, Carlos A. Driscoll, I Chestin, H Jungius, Y Darman, E Dinerstein, J Seidensticker, J Sanderson, S Christie, S J. Luo, M Shrestha, Y Zhuravlev, O Uphyrkina, Y V. Jhala, S P. Yadav, D G. Pikunov, N Yamaguchi, D E. Wildt, J D. Smith, Marker, Philip J. Nyhus, R Tilson, D W. Macdonald, S J. O'Brien

Faculty Scholarship

Recent genetic analysis has shown that the extinct Caspian Tiger (P. t. virgata) and the living Amur Tigers (P. t. altaica) of the Russian Far East are actually taxonomically synonymous and that Caspian and Amur groups historically formed a single population, only becoming separated within the last 200 years by human agency. A major conservation implication of this finding is that tigers of Amur stock might be reintroduced, not only back into the Koreas and China as is now proposed, but also through vast areas of Central Asia where the Caspian tiger once lived. However, under the current tiger conservation …


The Development And Morphology Of Zebrafish After Embryonic Ethanol Exposure, Frances Lee Jan 2012

The Development And Morphology Of Zebrafish After Embryonic Ethanol Exposure, Frances Lee

Honors Theses

Maternal consumption of alcohol may subject the fetus to fetal alcohol syndrome or fetal alcohol spectrum disorders (FAS or FASD). FAS/D is a public health problem, and affected children are defined by varying degrees of irreversible mental retardation, physical defects, behavioral issues, and vision problems from prenatal alcohol exposure (Riley et al. 2011). Recent studies on FAS have looked towards animal models, such as zebrafish, Danio rerio, that exhibit homologous physical and behavioral effects of alcohol (Bilotta et al. 2004). I exposed zebrafish embryos to low doses of ethanol (0.5% v/v or 1% v/v) in either chronic (at least 8 …


The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds [Presentation], Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College Jan 2011

The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds [Presentation], Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)

No abstract provided.


The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College Jan 2011

The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)

During the fall of 2011, the Colby Environmental Assessment Team (CEAT) studied the Serpentine connecting East Pond and North Pond. East and North Ponds are members of the larger seven-lake system known as the Belgrade Lakes, located in central Maine. There are over 5,500 lakes in Maine that contribute $6.7 billion to the economy annually through activities including boating, fishing, swimming etc. Additionally, Maine’s lakes are sources of municipal and agricultural water, act as flood buffers, and host a wide range of plant, animal, and fish life. Lakes in Maine are a crucial part society and should be studied and …


Do Male Physiological Condition And Territory Quality Affect Female Choice In The Brown Anole, Anolis Sagrei?, Sarah P. Flanagan Jan 2011

Do Male Physiological Condition And Territory Quality Affect Female Choice In The Brown Anole, Anolis Sagrei?, Sarah P. Flanagan

Honors Theses

Female mate choice is an important component of sexual selection because traits that influence male mate preference, such as physiology, and proficiency in acquiring resources, are favored. In lizards, the importance of mate choice remains unclear as reported results from experiments are contradictory. In this study, I investigated whether male physiology and territory quality are important to female mate choice for male Brown Anoles, Anolis sagrei. I tested the hypotheses that female A. sagrei prefer males with greater physiological capacities, and prefer higher quality territories, regardless of male phenotype. To test these, male A. sagrei were first rated for …


The Impact Of Tricaine Methanesulfonate, 2-Phenoxyethanol, And Carvone-Methyl Salicylate On The Innate Immune Response Of Zebrafish (Danio Rerio), Charles R. Wulff Jan 2011

The Impact Of Tricaine Methanesulfonate, 2-Phenoxyethanol, And Carvone-Methyl Salicylate On The Innate Immune Response Of Zebrafish (Danio Rerio), Charles R. Wulff

Honors Theses

Anesthesia plays a vital role in the maintenance of aquaculture species, where it is used to minimize stress during complex handling tasks such as transport, assessment, and harvesting. However, anesthetics have been shown to suppress the innate immune response, which could impact immunity and increase risk of infection. Tricaine methanesulfonate (MS-222) and 2-Phenoxyethanol (2-PE) represent two of the most commonly used anesthetics in aquaculture, with R-(+)-carvone, in the form of carvone-methyl salicylate (CMS) has recently been proposed as an alternative anesthetic for food fish. These three anesthetics were used to assess the influence of anesthetics on the immune system of …


Buffernomics: Assessing Willingness To Pay For Lake Conservation On North Pond And East Pond, Sophie D. Sarkar Jan 2011

Buffernomics: Assessing Willingness To Pay For Lake Conservation On North Pond And East Pond, Sophie D. Sarkar

Honors Theses

Hedonic property valuations in Maine have estimated that a one-meter decrease in water clarity can reduce shoreline property values by 4 to 16%. To avoid a loss on their lakefront investment, shoreline property owners have a particularly large incentive to conserve lake water quality. Nevertheless, while some shoreline residents voluntarily install vegetated buffers and actively participate in lake stewardship, others continue to ignore shoreline zoning laws at the expense of lake health. In this thesis, I examine the dichotomy of active and indifferent shoreline residents by analyzing the motivations that distinguish residents who are willing to pay (WTP) for and …


Zooplankton Of The Belgrade Lakes: The Influence Of Top-Down And Bottom-Up Forces In Family Abundance, Kimberly M. Bittler Jan 2011

Zooplankton Of The Belgrade Lakes: The Influence Of Top-Down And Bottom-Up Forces In Family Abundance, Kimberly M. Bittler

Honors Theses

The purpose of this study was to assess the abundance and family diversity of zooplankton communities in the Belgrade Lakes, and to identify the broad scale and local variables that structure zooplankton communities in this region. The local effects of shoreline development and the presence of macrophyte patches were compared to larger scale variables, such as watershed wide residential development. Zooplankton are an intermediate link in the freshwater food web, and communities respond both to predation pressures as well as nutrient inputs. Shoreline development was expected to influence zooplankton densities by the increased nutrient inputs via erosion off developed sites …


Biomass Energy At Colby College, Rachel E. Baron Jan 2011

Biomass Energy At Colby College, Rachel E. Baron

Honors Theses

In light of growing concern regarding the effects of global climate change, Colby College signed the American College and University Presidents’ Climate Commitment (ACUPCC) in 2008. Through this pledge, Colby has committed to reducing carbon emissions in its Climate Action Plan (IPCC 2007; CCAP 2010). The College seeks to be carbon neutral by 2015 (CCAP 2010). This will be accomplished through a variety of mechanisms, one of which includes the construction of a biomass facility to replace most of the oil currently used for heating (CCAP 2010).

Anthropogenic global climate change has been documented by many scientists, but was widely …


The One That Carries You Away: Essays, Blair S. Braverman Jan 2011

The One That Carries You Away: Essays, Blair S. Braverman

Honors Theses

What is environmental writing? Phil Condon, author and professor at the University of Montana's Environmental Writing Institute, defines it as any piece of writing in which an important factor is nonhuman—be it animal, place, weather, et cetera. At the same time, he acknowledges that the primary limitation of this definition is its lack of limitations; because humans are constantly interacting with—and affected by—the nonhuman, virtually any piece of writing could be considered environmental. The Association for the Study of Literature and the Environment (ASLE), the nation's predominant organization for the academic study of environmental writing, defines itself through its focus …


Impacts Of Shoreline Development On The Littoral Zone Of Great Pond, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2010

Impacts Of Shoreline Development On The Littoral Zone Of Great Pond, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Great Pond (2012, 2010, 1998)

The Colby Environmental Assessment Team (CEAT) investigated the littoral zone of Great Pond in the Belgrade Lakes region of central Maine. Data collection occurred in September and October and analysis followed in October and November of 2010. Physical, biological, and chemical parameters were assessed to examine the impacts of shoreline development on the health of the littoral community. The littoral zone and adjacent riparian areas were sampled to allow comparison of aquatic and terrestrial parameters among different levels of shoreline development.


Where The Tiger Survives, Biodiversity Thrives, Philip J. Nyhus, Ronald Tilson Jan 2010

Where The Tiger Survives, Biodiversity Thrives, Philip J. Nyhus, Ronald Tilson

Faculty Scholarship

No abstract provided.


Quite A Year And New Life For Panthera Tigris: The St. Petersburg Declaration And The Future Of Wild Tigers, Philip J. Nyhus, Lisa Ann Tekancic Jan 2010

Quite A Year And New Life For Panthera Tigris: The St. Petersburg Declaration And The Future Of Wild Tigers, Philip J. Nyhus, Lisa Ann Tekancic

Faculty Scholarship

No abstract provided.


Family Ties: Mainstream Environmentalists' Understanding Of Radical Environmentalism In America, Zachary W. Ezor Jan 2010

Family Ties: Mainstream Environmentalists' Understanding Of Radical Environmentalism In America, Zachary W. Ezor

Honors Theses

Environmentalism in the United States manifests itself in numerous ways. While American environmentalists have been grouped into broad camps over the years, observers have struggled to accurately classify the different components of the movement. Lately, environmentalists have been characterized based on their chosen modus operandi. Environmentalists who employ typical interest group tactics of policy advocacy and accept the notion of political compromise can generally be called 'mainstream.' Alternatively, those environmentalists who employ non-conventional strategies like direct action and take a no-compromise stance on environmental issues are typically described as 'radical.' Despite these distinctions, both radical and mainstream environmentalists are parts …


Assessing Genetic Differentiation Among Populations Of The Invasive Plant Impatiens Glandulifera In Maine, Jordan R. Schoonover Jan 2010

Assessing Genetic Differentiation Among Populations Of The Invasive Plant Impatiens Glandulifera In Maine, Jordan R. Schoonover

Honors Theses

The annual herbaceous plant Impatiens glandulifera Royle is native to the Himalayas and is a significant invasive species in Europe. In the past century, it was introduced to the United States, where it has become established in 12 states. This study evaluated genetic differentiation among four Maine populations, to address a theory that posits hybridization of distinct lineages as a trigger for invasiveness. Regions of microsatellite repeats were evaluated at two polymorphic loci for 41 plants sampled from the four populations. A striking finding was that the observed heterozygosity was substantially higher than the heterozygosity expected from random combination of …


The Wheat Bzip Factor, Taabf1, Mediates Aba-Induced Gene Expression In Bombarded Barley Aleurone Layers, Benjamin R. Keyser Jan 2010

The Wheat Bzip Factor, Taabf1, Mediates Aba-Induced Gene Expression In Bombarded Barley Aleurone Layers, Benjamin R. Keyser

Honors Theses

The plant hormone Abscisic acid (ABA) plays a central role in maturation and germination in seeds, as well as mediating adaptive responses to abiotic environmental stresses. ABA induces the expression of many genes, including late-embryogenesis-abundant genes such as HVA1. To elucidate the ABA signaling pathway leading to HVA1 expression, we focus on the bZIP factor TaABF1. Analysis of the interplay between ABA and TaABF1 in the aleurone cells of imbibing cereal grains indicated that the two are not additive in their induction of the HVA1 promoter. A synthetic ABA analog, PBI-51, did not specifically inhibit the effect of exogenous ABA …


The Differential Roles Of D-Pax2 Variants In Regulating Drosophila Eye And Bristle Development, Colin J. O’Shea Jan 2010

The Differential Roles Of D-Pax2 Variants In Regulating Drosophila Eye And Bristle Development, Colin J. O’Shea

Honors Theses

The ability to appropriately interact with the environment is crucial to an organism’s survival. The establishment of functional sensory systems, such as the bristles and eyes in Drosophila, is a critical event during the development of the organism. The transcription factor D Pax2 is involved in the differentiation of the shaft and glial cells in the developing bristle (Kavaler et al., Dev, 126:2261-2272, 1999) and of the cone and primary pigment cells in the developing eye (Fu and Noll, Genes Dev, 11:389-405, 1997). How D-Pax2 contributes to distinct differentiative pathways in different cell types is not known. Recent work by …


The Role Of Taabf1 In Abscisic Acid-Mediated Suppression Of 𝒶-Amylase Gene Expression In Cereal Grains, Lauren J. Harris Jan 2010

The Role Of Taabf1 In Abscisic Acid-Mediated Suppression Of 𝒶-Amylase Gene Expression In Cereal Grains, Lauren J. Harris

Honors Theses

The phytohormones gibberellin (GA) and abscisic acid (ABA) regulate important developments events in germinating seeds. Specifically, GA induces the expression of hyrolase genes, like the α-amylase gene Amy32b, which mobilizes starch reserves to be used by the embryo, and ABA suppresses this induction. Recent advancements identified ABA and GA receptors and key components in the signaling pathways, however, the mechanism of crosstalk between the hormones remains largely unknown. To further elucidate the mechanism of ABA suppression of GA-induced genes, we focused on the transcription factor TaABF1, a member of the ABA response element binding factor family. TaABF1 has been shown …


Patterns Of Apoptotic Poly(Adp-Ribose) Polymerase Cleavage Induced By Laromustine And Its Analogs, Adam N. Paine Jan 2010

Patterns Of Apoptotic Poly(Adp-Ribose) Polymerase Cleavage Induced By Laromustine And Its Analogs, Adam N. Paine

Honors Theses

The anticancer prodrug Laromustine (VNP40101M) has produced promising remission rates in clinical trials among leukemic patients relative to currently available chemotherapeutics. Such improvements demand that the agent’s mechanism of action be elucidated. This study aimed to determine the role of poly(ADP-ribose) polymerase (PARP) in Laromustine-induced cell death. Previous studies indicated that the methyl isocyanate produced upon activation of Laromustine is largely responsible for its effective induction of apoptosis. Results reported herein strongly support the activation of a PARP-dependent apoptotic pathway by Laromustine’s carbamoylating and chlorethylating subspecies. Furthermore, it is evident that the Laromustine-induced PARP-dependent apoptosis is primarily attributable to methyl …


Reintroduction Of The Chinese Tiger, Philip J. Nyhus, Urs Breitenmoser, Ron Tilson Jan 2009

Reintroduction Of The Chinese Tiger, Philip J. Nyhus, Urs Breitenmoser, Ron Tilson

Faculty Scholarship

No abstract provided.


A Watershed Analysis Of Salmon Lake And Mcgrath Pond: Implications For Water Quality And Land Use Management, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College Jan 2009

A Watershed Analysis Of Salmon Lake And Mcgrath Pond: Implications For Water Quality And Land Use Management, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: Salmon Lake and McGrath Pond (2009, 1993)

In the summer and fall of 2009, the Colby Environmental Assessment Team (CEAT) studied the water quality of Salmon Lake and McGrath Pond, located in the Belgrade Lakes Region of Maine. The physical, chemical and biological characteristics of water quality were measured and analyzed to evaluate the current health of these lakes. Water quality data collected during the summer and fall of 2009 were compared with data from previous years to study the historic water quality trends. Land use patterns in the Salmon/McGrath watershed were also examined to investigate their impact on the lake water quality. The water quality trends …


The Effect Of Glutamate On Neurite Outgrowth In Fiddler Crab (Uca Pugilator) X-Organ Cells, Ruth B. Langton Jan 2009

The Effect Of Glutamate On Neurite Outgrowth In Fiddler Crab (Uca Pugilator) X-Organ Cells, Ruth B. Langton

Honors Theses

Glutamate is the primary excitatory neurotransmitter in the mammalian central nervous system. It is of particular interest because of its supposed role in the processes of learning and memory, and also because of its potential toxic effects that have been linked to neurodegenerative diseases, such as Alzheimer’s and Parkinson’s. Although glutamate is necessary for normal cell functioning, high levels of glutamate receptor activation can result in cell death, a phenomenon known as excitotoxicity. It has been suggested that glutamate also plays an important role in the insect and crustacean nervous systems, allowing for the examination of excitotoxicity in these organisms. …


The Effects Of Eating Behaviors And Exercise Patterns On The Processing Of Food And Exercise Related Stimuli, Carrie Potter Jan 2009

The Effects Of Eating Behaviors And Exercise Patterns On The Processing Of Food And Exercise Related Stimuli, Carrie Potter

Honors Theses

The effectiveness of Cognitive Behavioral Therapy (CBT) for eating disorders has established a link between cognitive processes and unhealthy eating behaviors. However, the relationship between individual differences in unhealthy eating behaviors that are not related to clinical eating disorders, such as overeating and restrained eating, and the processing of food related verbal stimuli remains undetermined. Furthermore, the cognitive processes that promote unhealthy and healthy exercise patterns remain virtually unexplored by previous research. The present study compared individual differences in attitudes and behaviors around eating and exercise to responses to food and exercise-related words using a Lexical Decision Task (LDT). Participants …


Foundations And Interpretations Of Quantum Mechanics, Cory Johnson May 2008

Foundations And Interpretations Of Quantum Mechanics, Cory Johnson

Honors Theses

The first famous thought experiment of Einstein gives rise to his theories of relativity, the bedrock of modern astrophysics and cosmology. His second famous thought experiment begins the investigation into the foundations of quantum mechanics. It leads to a paradox, inspiring various 'no-go' theorems proven by Bell, Kochen, and Specker. Physicists and philosophers worldwide become increasingly dissatisfied with the probabilistic complementarity interpretation (Born-Bohr) and eventually offer their own accounts of the theory. By the end of the 20th century two alternative approaches stand out as the best candidates: Both the hidden variables interpretation (de Broglie-Bohm) and the many worlds interpretation …


Effects Of Context Of Natural And Artifactual Objects On Categorization, Linsey Walker May 2008

Effects Of Context Of Natural And Artifactual Objects On Categorization, Linsey Walker

Honors Theses

Categorization of animals and vehicles in different contexts was investigated in three experiments using event related potentials (ERPs). The presence of a background and congruency of the background in relation to the object were both manipulated in order to determine the effects of context on visual processing. In Experiment 1, adults were presented with images of animals and vehicles in two conditions: situated in a congruent context (e.g. an animal in a field) and in the absence of a context (an animal in a white homogeneous background). In experiment 2, adults were presented with images of animals and vehicles in …


A Watershed Analysis Of Pattee Pond: Implications For Water Quality And Land Use Management, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2008

A Watershed Analysis Of Pattee Pond: Implications For Water Quality And Land Use Management, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Pattee Pond (2008, 1992)

The Colby Environmental Assessment Team (CEAT) investigated the impact of land use patterns on the water quality of Pattee Pond in Winslow, Maine, during the summer and fall of 2008. Physical, chemical, and biological characteristics of water quality were analyzed to evaluate the current health of the lake. Data collected were compared with previous studies conducted by the Maine Department of Environmental Protection (DEP) and CEAT to examine changes in water quality and land use over time. Trends in Pattee Pond water quality suggest an improvement since the 1970s. However, the lake is still experiencing algal blooms resulting from phosphorus …


Cytotoxicity Of Diepoxybutane And Epichlorohydrin In Relation To Stages Of The Cell Cycle, Megan L. Watts Jan 2008

Cytotoxicity Of Diepoxybutane And Epichlorohydrin In Relation To Stages Of The Cell Cycle, Megan L. Watts

Honors Theses

Work conducted in the Millard Biochemistry Research Laboratory examines the dual nature of molecules as carcinogens and anti-tumor agents through the molecular mechanisms of duplex DNA damage by bifunctional alkylating agents. Diepoxybutane (DEB) and epichlorohydrin (ECH) are polar molecules that form covalent DNA interstrand lesions by cross-linking the N7 position of deoxyguanosine residues. A recent experiment indicated that ECH preferentially targets nuclear DNA over mitochondrial DNA, whereas DEB shows similar rates of lesion formation for both loci. It was concluded that preferential targeting of nuclear DNA results from relatively poor uptake of ECH across the mitochondrial membrane. The objective of …


The Effect Of Orientation To Growing Season Sunlight On Stomatal Parameters Of Q. Rubra In The Belgrade Lakes Region, Central Maine, Rachel G. Daly Jan 2008

The Effect Of Orientation To Growing Season Sunlight On Stomatal Parameters Of Q. Rubra In The Belgrade Lakes Region, Central Maine, Rachel G. Daly

Honors Theses

Stomatal frequencies of fossil-plant species are used to estimate past pCO2 levels based on the physiological functions of living taxa. Numerous studies have shown that there is an inverse relationship between pCO2 and stomatal frequency parameters. As levels of pCO2 increase, the Stomatal Density (SD) and Stomatal Index (SI) decrease. However, pCO2 is not the only factor affecting SD and SI values, which are a product of leaf growth and expansion. Stomatal characteristics differ between genera, and studies also have shown that SD and light intensity have a positive correlation. The present study hypothesizes that SD and SI are not …


The Pollination Biology And Mating System Of A Peripheral Population Of Witheringia Solanacea (Solanaceae), Timothy Miller Jan 2008

The Pollination Biology And Mating System Of A Peripheral Population Of Witheringia Solanacea (Solanaceae), Timothy Miller

Honors Theses

Pollinator visitation rates over the life of a flower are determined by pollinator abundance and floral longevity. If flowers are not visited frequently enough, pollen limitation may occur, favoring the evolution of self-compatibility (SC). In plant species with varying SC levels, central populations often are self-incompatible (SI) and peripheral populations are SC. Witheringia solanacea (Solanaceae) is a species that follows this trend with the exception of one population in the Monteverde Cloud Forest Reserve, which is peripheral yet SI. I investigated this population using multiple techniques including floral bagging, pollinator observations, microsatellite analysis, and floral longevity manipulations. My results confirmed …


Effects Of Alcohol And Training On Exercise Performance And Muscle Recovery Biochemistry In The Brown Anole (Anolis Sagrei), Maryclaire Mcgovern Jan 2008

Effects Of Alcohol And Training On Exercise Performance And Muscle Recovery Biochemistry In The Brown Anole (Anolis Sagrei), Maryclaire Mcgovern

Honors Theses

Contrary to previous research, training may improve exercise performance in a lizard, the brown anole. A brief, two-week training period resulted in increased performance speed and distance before exhaustion in trained lizards. Trained lizards were also able to more effectively use leg glycogen stores, however each of these improvements were not found in lizards treated with alcohol. Liver glycogen concentrations were also lower in alcohol-treated lizards, and patterns of liver glycogen concentrations during recovery indicate some hepatic lactate gluconeogenesis.