Fundamental domains for proper affine actions of Coxeter groups in three dimensions

We study proper actions of groups $G \cong \Z/2\Z \ast \Z/2\Z \ast \Z/2\Z$ on affine space of three real dimensions. Since $G$ is nonsolvable, work of Fried and Goldman implies that it preserves a Lorentzian metric. A subgroup $\Gamma < G$ of index two acts freely, and $\R^3/\Gamma$ is a Margulis spacetime associated to a hyperbolic surface $\Sigma$. When $\Sigma$ is convex cocompact, work of Danciger, Gu{\'e}ritaud, and Kassel shows that the action of $\Gamma$ admits a polyhedral fundamental domain bounded by crooked planes. We consider under what circumstances the action of $G$ also admits a crooked fundamental domain. We show that it is possible to construct actions of $G$ that fail to admit crooked fundamental domains exactly when the extended mapping class group of $\Sigma$ fails to act transitively on the top-dimensional simplices of the arc complex of $\Sigma$. We also provide explicit descriptions of the moduli space of $G$ actions that admit crooked fundamental domains.

SOCIAL STRUCTURE OF ASIAN ELEPHANTS (ELEPHAS MAXIMUS) IN SRI LANKA

Asian elephants (Elephas maximus) are critically endangered and live in fragmented populations spread across 13 countries. Yet in comparison to the African savannah elephant (Loxodonta africana), relatively little is known about the social structure of wild Asian elephants because the species is mostly found in low visibility habitat. A better understanding of Asian elephant social structure is critical to mitigate human-elephant conflicts that arise due to increasing human encroachments into elephant habitats. In this dissertation, I examined the social structure of Asian elephants at three sites: Yala, Udawalawe, and Minneriya National Parks in Sri Lanka, where the presence of large open areas and high elephant densities are conducive to behavioral observations. First, I found that the size of groups observed at georeferenced locations was affected by forage availability and distance to water, and the effects of these environmental factors on group size depended on site. Second, I discovered that while populations at different sites differed in the prevalence of weak associations among individuals, a core social structure of individuals sharing strong bonds and organized into highly independent clusters was present across sites. Finally, I showed that the core social structure preserved across sites was typically composed of adult females associating with each other and with other age-sex classes. In addition, I showed that females are social at all life stages, whereas males gradually transition from living in a group to a more solitary lifestyle. Taking into consideration these elements of Asian elephant social structure will help conservation biologists develop effective management strategies that account for both human needs and the socio-ecology of the elephants.

BLACK SURVIVAL POLITICS: ORGANIZED MOBILIZATION STRATEGIES IN AFRICAN AMERICAN COMMUNITIES TO END THE HIV/AIDS EPIDEMIC

The purpose of this study is to examine organizational patterns of African American activism in response the HIV/AIDS epidemic. Given their political, economic, and social disenfranchisement, African Americans have historically developed protest and survival strategies to respond to the devaluation of their lives, health, and well-being. While Black protest strategies are typically regarded as oppositional and transformative, Black survival strategies have generally been conceptualized as accepting inequality. In the case of HIV/AIDS, African American religious and non-religious organizations were less likely to deploy protest strategies to ensure the survival and well-being of groups most at risk for HIV/AIDS—such as African American gay men and substance abusers. This study employs a multiple qualitative case study analysis of four African American organizations that were among the early mobilizers to respond to HIV/AIDS in Washington D.C. These organizations include two secular or community-based organizations and two Black churches or faith-based organizations. Given the association of HIV/AIDS with sexual sin and social deviance, I postulated that Black community-based organizations would be more responsive to the HIV/AIDS-related needs and interests of African Americans than their religious counterparts. More specifically, I expected that Black churches would be more conservative (i.e. maintain paternalistic heteronormative sexual standards) than the community-based organizations. Yet findings indicate that the Black churches in this study were more similar than different than the community-based organizations in their strategic responses to HIV/AIDS. Both the community-based organizations and Black churches drew upon three main strategies in ways that politicalize the struggle for Black survival—or what I regard as Black survival politics. First, Black survival strategies for HIV/AIDS include coalition building at the intersection of multiple systems of inequality, as well as on the levels of identity and community. Second, Black survival politics include altering aspects of religious norms and practices related to sex and sexuality. Third, Black survival politics relies on the resources of the government to provide HIV/AIDS related programs and initiatives that are, in large part, based on the gains made from collective action.