Honors Projects
Showing 281 - 290 of 564 Items
Hybridization dynamics of a newly discovered parrotfish swarm in the Tropical Eastern Pacific
Date: 2017-05-01
Creator: Robert Barron
Access: Open access
- Hybrid zones and their dynamics are important in the understanding of the genetic basis of reproductive isolation and speciation. This study seeks to investigate the hybridization dynamics of a Scarus hybrid swarm within the Tropical Eastern Pacific (TEP) that includes four phenotypically distinct species: S. perrico, S. ghobban, S. rubroviolaceus, and S. compressus. Genetic and population structure analyses of four nuclear loci and a mitochondrial locus revealed that one of the four species, S. compressus, was the result of two different hybrid crosses: S. perrico ✕ S. rubroviolaceus and S. perrico ✕ S. ghobban. A NewHybrids model indicated that most of the S. compressus samples were F1 hybrids, but 21% of the S. compressus sample was classified as “parentals” which could also be explained by the presence of either F2 hybrids or backcrosses with S. compressus phenotypes, given the relatively low power of the nuclear data set (4 loci) to resolve complex hybrid genotypes. Significant mito-nuclear discordance in all three non-hybrid species is consistent with an evolutionary effect of backcrossing between F1 hybrids and “pure” species. This study reveals a relative ease of hybridization between parrotfish taxa separated by an estimated 4.5 million years of isolation and opens the door to further studies on the potential effects of gene flow across old species boundaries and perhaps the formation of new species by hybrid speciation in a diverse clade of tropical reef fish. Elucidating the nature of potentially “deep” F2 crosses and backcrosses within the TEP Scarus hybrid system will allow us to better understand the effects of hybridization on evolution and speciation on both a micro- and macro-ecological scale.
Tracking photosynthetic seasonality at needle and forest scales in pines experiencing mild winters Access to this record is restricted to members of the Bowdoin community. Log in here to view.
- Restriction End Date: 2025-06-01
Date: 2022-01-01
Creator: Sara Elizabeth Nelson
Access: Access restricted to the Bowdoin Community
The sex specific effects of acute ketamine treatment on parvalbumin and anxiety and depression following early life adversity Access to this record is restricted to members of the Bowdoin community. Log in here to view.
- Restriction End Date: 2025-06-01
Date: 2022-01-01
Creator: Seneca N. Ellis
Access: Access restricted to the Bowdoin Community
Sorption of Cationic Heterocyclic Amines to Soils: Effects of Charge Delocalization and other Factors Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2023-01-01
Creator: Mariah McKenzie
Access: Access restricted to the Bowdoin Community
Is Faith the Ultimate Divider?: The Intersections Between Religion and Political Behavior in the United States
Date: 2023-01-01
Creator: Ryan Supple
Access: Open access
- This thesis examines the complex relationship between religiosity and voting behavior in the United States. In a country where religion has diminished in importance over time, it seems rather fascinating that it still plays such a large role in the inner-workings of American politics. Chapter One analyzes the varying ways in which scholars have approached emergent political trends between religious groups, particularly with regards to political parties, voting behavior, and government representation. Chapter Two extends this analysis to the American National Election Studies (ANES), a national survey distributed to random samples of Americans during election seasons. The information from the ANES facilitated a more in-depth analysis of how individuals with varying levels of affiliations have interacted with politics, such as ideologies, affiliations, and feelings towards religiously salient political issues. Lastly, Chapter 3 focuses on college-aged students, using both the UCLA's CIRP Freshman Survey and the Bowdoin College Polar Poll, to evaluate how America's educated youth are interacting with politics. These data allowed for a more proper investigation into how a historically unreligious portion of the population interact with religion today, and how this may affect America's religious climate in the future, as students eventually grow into educated professionals and further immerse themselves into politics. Ultimately, this paper suggests that a growing political polarity has coincided with polarization in religion, with two coalitions-- a religious and non religious one moving in opposite directions, thus amounting to further divisions and misunderstandings between the American public.
Reframing Mourning: Liberatory Grief in Post-Tragedy Chinese American Women’s Fiction
Date: 2024-01-01
Creator: Sophia Li
Access: Open access
- My project approaches discussions of Asian American melancholia and mourning with a specific focus on contemporary Chinese American women’s fiction. Scholars such as David Eng, Shinhee Han, and Anne Anlin Cheng have long spotlighted the prevalence of depression among Asian American populations, particularly those with immigrant backgrounds, and they variously adopt psychoanalytic approaches to understand Asian American mental health and intersectional identities. Looking beyond psychoanalytic models, my project focuses on the works of Yiyun Li, Jenny Zhang, and K-Ming Chang to explore diverse forms of post-tragedy positionality. I read the authors paratextually, not only to locate them within legacies of diasporic fiction and intersectional auto-writing but also to highlight their critically self-reflexive authorship. I study novels and characters depicting complex processes of mourning, ultimately proposing a reading that views them not only as resisting complete recovery but as forging pathways toward liberatory grief.
Poverty Ends with a 12 Year Old Girl: Empowerment and the Contradictions of International Development
Date: 2017-05-01
Creator: Meghan Elizabeth Bellerose
Access: Open access
- This thesis argues that international development programs focused on adolescent girls reproduce problematic and contradictory depictions of girls in the global South. Using Girl Effect marketing materials and interviews with INGO staff, I demonstrate that present-day international aid programs center on the neoliberal notion that an empowered adolescent girl holds the unique potential to end global poverty. Through empowerment programs, girls are encouraged to recognize their agency and take personal responsibility for improving the wellbeing of their communities. However, I argue that even as development leaders claim that an empowered adolescent girl is a source of indefatigable strength who can transform her community, they carry a deep conviction that such a feat is not possible without significant Western aid. Despite the empowerment rhetoric that The Girl Effect and related international initiatives espouse, their programs depict adolescent girls in the developing world as vulnerable and oppressed by poverty, local men, and their cultures. Thus, Western donors are called upon to save “Third World” adolescent girls. I argue that these contradictions in the language of international development contribute to the perception of girls in the global South as weak, inferior, and homogenous and lead to the establishment of programs that strengthen inequitable structures and sideline girls’ sexual rights.
Gendered Subjectivity in Refugee Resettlement Processes: From Somalia to Lewiston, ME
Date: 2018-01-01
Creator: Elena Gleed
Access: Open access
- Refugee Resettlement to the United States is a globalized and transnational process of making home. After Somali state collapse in 1991, more than a million displaced people fled to refugee camps across the Kenyan border. Today, over 12,000 Somali people now live in Lewiston, ME, an old mill town located along the Androscoggin River. As refugees are resettled by the United Nations High Commissioner for Refugees they enter a system created over fifty years ago in response to World War II. Using post-colonial and feminist scholarship, this project analyses the “female refugee” subject as she appears in the official discourse of resettlement processes. I trace the historical emergence of this subjectivity from an individual and work-based neoliberal American ethos to non-governmental organizations run by Somali women in Lewiston. Drawing from document analysis and ethnographic interviews, this paper explores the how Somali women are made to be “new American workers” in a process that combines western liberal feminism with ideas of integration and cultural orientation to the United States.
Mitochondrial adaptation in the green crab hybrid zone of the Gulf of Maine
Date: 2024-01-01
Creator: Jared Lynch
Access: Open access
- The mitochondrial genome has historically been relegated to a neutral genetic marker, but new evidence suggests mitochondrial DNA to be a target for adaptation to environmental stress. The invasive European green crab (Carcinus maenas) exemplifies this in the Gulf of Maine’s hybrid zone, where interbreeding populations exhibit thermal tolerances influenced by mitochondrial genotype. To better understand the mechanism behind this phenomenon, the effect of mitochondrial genotype on mitochondrial activity was tested by measuring mtDNA copy number (mtCN) and the activity of complex I, II, and IV of the electron transport system via high-resolution respirometry. Mitochondria isolated from frozen heart tissue were measured at three temperature points—5°C, 25°C, and 37°C—to represent thermal stresses and a control. It was predicted that cold-adapted haplogroups would exhibit both higher mtCN and increased activity for each complex, either across all temperatures or exclusively at 5°C compared to a warm-adapted haplogroup. Initial comparisons of mitochondria from fresh and frozen tissue at 25°C found lower activity for complex II and IV in frozen extracts, but they continued to be used for convenience. No differences were observed across haplogroups for mtCN or high-resolution respirometry, suggesting that mitochondrial activity does not underlie differences in thermal tolerance. However, temperature greatly influenced activity measurements with complex II and IV exhibiting the highest rates at 37°C while complex I exhibited optimal activity at 25°C. This study represents the first of its kind for C. maenas, providing a foundation for future experiments to continue exploring mitochondria in the context of adaptive evolution.
Salud Callejera: Mobilizing Cuidado at the Margins of Neoliberalism; Reimagining Care for People Experiencing Homelessness in Buenos Aires
Date: 2019-05-01
Creator: Brandon Morande
Access: Open access
- On any given night, thousands of individuals sleep on the streets of the Ciudad Autónoma de Buenos Aires. Without secure housing, people in situación de calle (experiencing homelessness) suffer elevated rates of physical trauma, transmissible and chronic diseases, and symptoms of depression. Nevertheless, two-thirds of this population do not receive annual health consultations, with the majority solely accessing the emergency department when their conditions severely worsen. This study finds that municipal services and, to a lesser extent, the public health system render individuals responsible for housing insecurity by adopting a neoliberal subjectivity of homo economicus, medicalizing poverty as a symptom of psychosocial illness potentially curable through economic and social rehabilitation. Those who do not conform with such pathologization or other employment-based demands confront heightened criminalization and exclusion from care services. As an alternative response, this project investigates the actions of civil society networks, which employ a contrary notion of homo politicus, reimagining care as a collective right and site of political mobilization. This thesis draws upon interviews with people experiencing or at risk of homelessness, members of civil society organizations, public health providers, and municipal social workers, as well as observations from street-outreach.