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Humans have evolved in many ways. Just look at how life for mankind has changed over the past few decades. It is amazing how different life can be in just a short amount of time. While it is evident that we have impacts of the environment, it should be just

Humans have evolved in many ways. Just look at how life for mankind has changed over the past few decades. It is amazing how different life can be in just a short amount of time. While it is evident that we have impacts of the environment, it should be just as evident that we impact the animals around us. However, there are a few subtle ways in which we impact the evolution of life.
Through man-made structures, human interference, artificial lights at night, and electromagnetic fields we have caused animals and insects to evolve and fit these new environments. While we tail the world around us to convince ourselves, the animals also living in these environments need to adapt to survive. In this essay, I will discuss how the affects mentioned above have cause crows, moths, snails, bobcats, blackbirds, mosquitoes, elephants, diurnal animals, fireflies, dung beetles, birds and bats to evolve. The adaptations these organisms made were caused by the subtle ways in which we have impact the landscapes around us.
ContributorsFikse, Sydney D (Author) / Sterner, Beckett (Thesis director) / Pfeifer, Susanne (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Phenotypic evolution is an essential topic within the general field of evolution. Theoretically, the outcome of phenotypic evolution may be influenced by factors such as genetic background and the interaction of natural selection and genetic drift. To gain empirical evidence for testing the effects of those factors, we used eight

Phenotypic evolution is an essential topic within the general field of evolution. Theoretically, the outcome of phenotypic evolution may be influenced by factors such as genetic background and the interaction of natural selection and genetic drift. To gain empirical evidence for testing the effects of those factors, we used eight long-term evolved Escherichia coli populations as a model system. These populations differ in terms of genetic background (different mutation rates) as well as bottleneck size (small- and large-magnitude). Specifically, we used a plate reader to measure three growth-related traits: maximum growth rate (umax), carrying capacity (Kc), and lag time (Lt) for 40 clones within each population. For each trait we quantified the change in mean per generation, the change in variance per generation, and the correlation coefficient between pairs of traits. Interestingly, we found that the small and large bottleneck populations of one background displayed clear, distinguishing trends that were not present within the populations of the other background. This leads to the conclusion that the influence of selection and drift on a population’s phenotypic outcomes is itself influenced by the genetic background of that population. Additionally, we found a strong positive correlation between umax and Kc within each of the high-mutation populations that was not consistent with our neutral expectation. However, the other two pairs did not exhibit a similar pattern. Our results provide a novel understanding in the relationship between the evolution of E. coli growth-related phenotypes and the population-genetic environment.
ContributorsGonzales, Jadon (Co-author, Co-author) / Lynch, Michael (Thesis director) / Ho, Wei-Chin (Committee member) / Geiler-Samerotte, Kerry (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Cancer rates vary significantly across tissue type and location in humans, driven by clinically relevant distinctions in the risk factors that lead to different cancer types. Despite the importance of cancer location in human health, little is known about tissue-specific cancers in non-human animals. A comparison of cancer prevalence across

Cancer rates vary significantly across tissue type and location in humans, driven by clinically relevant distinctions in the risk factors that lead to different cancer types. Despite the importance of cancer location in human health, little is known about tissue-specific cancers in non-human animals. A comparison of cancer prevalence across the tree of life can give insight into how evolutionary history has shaped various mechanisms of cancer suppression. Here, we explore whether species-level life history strategies are associated with differences in mammary neoplasia rates across mammals. We propose that the same patterns of cancer prevalence that have been reported across species will be maintained at the tissue-specific level. We used a phylogenetic regression on 15 life history traits across 112 mammalian species to determine the correlation between a life history trait and how it relates to mammary neoplasia prevalence. A greater risk of mammary neoplasia was found in the characteristics associated with fast life history organisms and a lower risk of mammary neoplasia was found in the characteristics associated with slow life history organisms. With this analysis, a framework is provided for how different life history modalities can influence cancer vulnerability.
ContributorsMajhail, Komal Kaur (Co-author) / Majhail, Komal (Co-author) / Maley, Carlo (Thesis director) / Boddy, Amy (Committee member) / Compton, Zachary (Committee member) / College of Health Solutions (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description

The study of macaque monkeys harbors advancements in the field of biomedical research. It is imperative to understand the genetic composition of different species of macaques to assess their accuracy as non-human primate (NHP) models for disease detection and treatment assessments. We sought to characterize the hybridization and admixture of

The study of macaque monkeys harbors advancements in the field of biomedical research. It is imperative to understand the genetic composition of different species of macaques to assess their accuracy as non-human primate (NHP) models for disease detection and treatment assessments. We sought to characterize the hybridization and admixture of the Southeast Asian macaques using single nucleotide polymorphism markers and analyzing the populations on the mainland and the island. Using AMOVA tests and STRUCTURE analysis, we determined that there are three distinct populations: Macaca mulatta, M. fascicularis fascicularis, and M. f. aurea. Furthermore, the island species holds an isolated population of M. f. aurea that demonstrate high inbreeding and genetic uniqueness compared to the mainland species. Findings from this study confirm that NHP models may need to be modified or updated according to changing allelic frequencies and genetic drift.

ContributorsFalak, Asiya (Author) / Kanthaswamy, Sreetharan (Thesis director) / Oldt, Robert (Committee member) / Barrett, The Honors College (Contributor) / Computer Science and Engineering Program (Contributor) / School of Life Sciences (Contributor)
Created2022-05
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Description

Cancers of the reproductive tissues make up a significant portion of the cancer burden and mortality experienced by humans. Humans experience several proximal causative carcinogens that explain a portion of cancer risk, but an evolutionary viewpoint can provide a unique lens into the ultimate causes of reproductive cancer vulnerabilities. A

Cancers of the reproductive tissues make up a significant portion of the cancer burden and mortality experienced by humans. Humans experience several proximal causative carcinogens that explain a portion of cancer risk, but an evolutionary viewpoint can provide a unique lens into the ultimate causes of reproductive cancer vulnerabilities. A life history framework allows us to make predictions on cancer prevalence based on a species’ tempo of reproduction. Moreover, certain variations in the susceptibility and prevalence of cancer may emerge due to evolutionary trade-offs between reproduction and somatic maintenance. For example, such trade-offs could involve the demand for rapid proliferation of cells in reproductive tissues that arises with reproductive events. In this study, I compiled reproductive cancer prevalence for 158 mammalian species and modeled the predictive power of 13 life history traits on the patterns of cancer prevalence we observed, such as Peto’s Paradox or slow-fast life history strategies. We predicted that fast-life history strategists will exhibit higher neoplasia prevalence risk due to reproductive trade-offs. Furthering this analytical framework can aid in predicting cancer rates and stratifying cancer risk across the tree of life.

ContributorsDarapu, Harshini (Author) / Maley, Carlo (Thesis director) / Boddy, Amy (Committee member) / Compton, Zachary (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2022-05
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Description
Mutation rate is the rate of appearance for mutations to occur in a living organism. Studying and quantifying mutation rates and their evolution is important because mutations are the ultimate source of genetic variation and one of the reasons why evolution occurs. Much of the current research has investigated the

Mutation rate is the rate of appearance for mutations to occur in a living organism. Studying and quantifying mutation rates and their evolution is important because mutations are the ultimate source of genetic variation and one of the reasons why evolution occurs. Much of the current research has investigated the mutational rate increase. The evolution of reduced mutation rate, which can be favored by natural selection because the accumulation of too many mutations can be deleterious and result in death, is less studied. Therefore, this study will be focused on antimutators, which are mutations that result in a lowering of the mutation rate. Using Escherichia coli K-12 str. MG1655 as a model system, the effects and reasons for how MMR- background E. coli evolves lower mutation rates were studied. Here we show that the candidate antimutator in dnaE lowers the mutation rate in an experimentally evolved population of E. coli with MMR- background by using a mutation rate assay to demonstrate the difference between populations with and without the antimutator candidate. The results also suggest the importance of an antimutator for populational survival.
ContributorsGraham, Logan (Author) / Ho, Wei-Chin (Thesis director) / Lynch, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2022-05
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Description

Cells have mechanisms in place to maintain the specific lipid composition of distinct organelles including vesicular transport by the endomembrane system and non-vesicular lipid transport by lipid transport proteins. Oxysterol Binding Proteins (OSBPs) are a family of lipid transport proteins that transfer lipids at various membrane contact sites (MCSs). OSBPs

Cells have mechanisms in place to maintain the specific lipid composition of distinct organelles including vesicular transport by the endomembrane system and non-vesicular lipid transport by lipid transport proteins. Oxysterol Binding Proteins (OSBPs) are a family of lipid transport proteins that transfer lipids at various membrane contact sites (MCSs). OSBPs have been extensively investigated in human and yeast cells where twelve have been identified in Homo sapiens and seven in Saccharomyces cerevisiae. The evolutionary relationship between these well-characterized OSBPs is still unclear. Reconstructed OSBP phylogenies revealed that the ancestral Saccharomycotinan had four OSBPs, the ancestral Holomycotan had five OSBPs, the ancestral Holozoan had six OSBPs, the ancestral Opisthokont had three OSBPs, and the ancestral Eukaroyte had three OSBPs. Our analysis identified three clades of ancient OSBPs not present in animals or fungi.

ContributorsSingh, Rohan (Author) / Wideman, Jeremy (Thesis director) / Gile, Gillian (Committee member) / Barrett, The Honors College (Contributor) / School of Human Evolution & Social Change (Contributor) / School of Life Sciences (Contributor)
Created2022-05
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Pathogenic drug resistance is a major global health concern. Thus, there is great interest in modeling the behavior of resistant mutations–how quickly they will rise in frequency within a population, and whether they come with fitness tradeoffs that can form the basis of treatment strategies. These models often depend on

Pathogenic drug resistance is a major global health concern. Thus, there is great interest in modeling the behavior of resistant mutations–how quickly they will rise in frequency within a population, and whether they come with fitness tradeoffs that can form the basis of treatment strategies. These models often depend on precise measurements of the relative fitness advantage (s) for each mutation and the strength of the fitness tradeoff that each mutation suffers in other contexts. Precisely quantifying s helps us create better, more accurate models of how mutants act in different treatment strategies. For example, P. falciparum acquires antimalarial drug resistance through a series of mutations to a single gene. Prior work in yeast expressing this P. falciparum gene demonstrated that mutations come with tradeoffs. Computational work has demonstrated the possibility of a treatment strategy which enriches for a particular resistant mutation that then makes the population grow poorly once the drug is removed. This treatment strategy requires knowledge of s and how it changes when multiple mutants are competing across various drug concentrations. Here, we precisely quantified s in varying drug concentrations for five resistant mutants, each of which provide varying degrees of drug resistance to antimalarial drugs. DNA barcodes were used to label each strain, allowing the mutants to be pooled together for direct competition in different concentrations of drug. This will provide data that can make the models more accurate, potentially facilitating more effective drug treatments in the future.

ContributorsNewell, Daphne (Author) / Geiler-Samerotte, Kerry (Thesis director) / Schmidlin, Kara (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2022-05
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Description
Background: Cancer impacts the lives of millions of patients, families and caregivers annually
leading to chronic stress, a sense of powerlessness, and decreased autonomy. Social support may improve health empowerment and lead to increased perception of well-being.

Purpose: The purpose of this project was to evaluate the effectiveness of social support provided

Background: Cancer impacts the lives of millions of patients, families and caregivers annually
leading to chronic stress, a sense of powerlessness, and decreased autonomy. Social support may improve health empowerment and lead to increased perception of well-being.

Purpose: The purpose of this project was to evaluate the effectiveness of social support provided by a cancer support agency on health empowerment and perceived well-being in adults impacted by cancer.

Conceptual Framework: The Health Empowerment Theory maintains that perceived wellbeing is the desired outcome; mediated by health empowerment through social support, personal growth, and purposeful participation in active goal attainment.

Methods: Twelve adults impacted by cancer agreed to complete online questionnaires at
baseline and at 12 weeks after beginning participation in social support programs provided by a cancer support agency.
Instruments included: Patient Empowerment Scale, The Short Warwick-Edinburgh Mental Well-Being Scale (SWEMWBS), and The Office of National Statistics (ONS) Subjective Well-Being Questions.

Results: Four participants completed pre and post surveys. An increase was seen in
empowerment scores (pre M = 1.78, SD = 0.35 and post M = 3.05, SD = 0.42). There was no
increase in perceived well-being: SWEMWBS pre (M= 3.71, SD= 0.76), post (M= 3.57, SD=
0.65); ONS pre (M= 7.69, SD= 1.36), post (M= 6.59, SD= 1.52).

Implications: The data showed an increase in health empowerment scores after utilizing social support programs, lending support to the agency’s support strategies. It is recommended that the measures be included in surveys routinely conducted by the agency to continue to assess the impact of programming on health empowerment, and perceived well-being.
ContributorsO'Rourke, Suzanne (Author) / Velasquez, Donna (Thesis advisor)
Created2017-05-03
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Theories about the human origin in evolution and religion are fundamentally countering beliefs that are still debated to this day. This study continues to explore this relationship in the college population at a public university with the intention of targeting a diverse religious population. This research hopes to answer the

Theories about the human origin in evolution and religion are fundamentally countering beliefs that are still debated to this day. This study continues to explore this relationship in the college population at a public university with the intention of targeting a diverse religious population. This research hopes to answer the question: does having greater literacy in evolution lead to a noninterventionist perspective on evolution? The prediction is that evidence of increased evolution comprehension will influence students to have a more agnostic, or noninterventionist, view on evolution. An evolution class was given a survey that had two parts broken into demographic and evolution sections with one question that asks about compatibility between evolution and religion. This was given twice in a single semester to track the growth of evolution knowledge and any other differences. There were 265 students in the initial survey, but only 223 responses in the post-survey. The compatibility question had 8 statements that range from creationist to atheistic perspectives and was divided into two sides: interventionist (divine involvement) and noninterventionist (deity may be present but does not intervene). More than 70% of the class had a noninterventionist perspective on evolution despite the Christian categories being the second largest group students identified with after agnostic. The agnostic statement was the top choice followed by the atheistic answer on the noninterventionist side. Lastly, there was some growth of evolution knowledge for each religious category in the evolution section but is not significant for interpretation. Based on the collected data, it is not sufficient to answer the question and requires more data collection via a longitudinal study.

ContributorsLam, Monica (Author) / Kappes, Janelle (Thesis director) / Sterner, Beckett (Committee member) / Barrett, The Honors College (Contributor) / Watts College of Public Service & Community Solut (Contributor) / School of Life Sciences (Contributor)
Created2022-05