Call number: LD2668 .T4 1952 O7 / Master of Science

Call number: LD2668 .T4 1963 B37 / Master of Science

Thesis (Ph.D.)--York University, 2004. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 110-131). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ99145

Thesis (M.S.)--University of North Carolina at Greensboro, 2006. / Title from PDF title page screen. Advisor: Matina Kalcounis-Rüppell, R. Mark Brigham; submitted to the Dept. of Biology. Includes bibliographical references (p. 60-68).

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Supervisor: Walter Wilczynski. Vita. Includes bibliographical references. Also available from UMI.

All animals must integrate internal and environmental information into an appropriate behavior that ultimately aims to increases fitness. In order to investigate the proximate and ultimate mechanisms underlying adaptive behavior, I examined the role of neuroendocrine molecules at three distinct levels of biological organization. At the level of the individual, I demonstrate that steroid hormone receptors play distinct roles in modulating adaptive behavior, physiology and brain gene expression in dominant and subordinate African cichlid fish. At the level of the social community, I investigate how the behavior and physiology of one individual can affect the behavior, physiology, and brain gene expression of other community members. I found striking covariance patterns that implicate identifiable neuroendocrine pathways as mediators of specific social signals, establishing an important model to investigate the molecular basis of how behavioral phenotypes spread through communities. Finally, I investigate how the neurochemistry of the five major vertebrate classes has changed in a way that covaries with sensory integration, life history, and mating strategy. To address this question, I have laid an important theoretical framework to study the evolution of behavior as well as establishing neuroanatomical brain homologies across vertebrate lineages. I show that variation in where neurochemicals (dopamine, steroids, neuropeptides) are produced in the brain varies across vertebrates while where signals are received (ie receptors) are conserved, providing a novel theory of social brain evolution. In summary, I use a multidisciplinary approach to study hormonal contributions to the proximate and ultimate mechanisms of social behavior on many levels of biological organization and have contributed important novel insights that have significantly increased our understanding of the evolution of behavior and its neural and molecular underpinnings. / text

Steroid hormones play an important role in modulating behavioral responses to various social stimuli. However, relatively little is known about how hormones respond to social stimuli and their modulation of subsequent behavior. Variation in the hormonal regulation of behavior across species has complicated the overall understanding of the hormone-behavior dynamic. In order to further elucidate the interplay of hormones and behavior in social situations, we exposed males of the monogamous convict cichlid Amatitliana nigrofasciata to three social stimuli: gravid female, intruder male and nonsocial neutral stimulus. We used a repeated exposure paradigm to create behavioral profiles and explore how sex steroid hormones respond to and regulate social behavior. Results show clear behavioral profiles in different social situations with 11-KT acting as the active androgen, increasing in response to social stimuli. Pharmacological manipulations using androgen and estrogen receptor agonists and antagonists exposed complex control over digging behavior based on social context, showed a unique decrease in aggressive behavior due to blocking the androgen receptors and a ubiquitous drug effect on vertical display. Results create well defined context-specific behavior profiles and extends our understanding of particular social behavior and how sex steroid hormones are involved in social situations and the behavioral response. / text

Not available / text

This thesis is comprised of a literature review on the topic of social participation in the elderly, and a study examining the association between primary transportation mode used and social participation in community-dwelling seniors. A review of the literature showed that social participation in the elderly is associated with survival, health-related quality of life, functional ability, emotional well-being, and cognitive skills, and is also influenced by personal and environmental factors. The study indicated that primary mode of transportation used by seniors living in the community is associated with social participation; those driving, walking or using public transport had overall greater social participation than passengers and those using adapted transport/taxi. These findings are of interest to rehabilitation professionals and researchers working in gerontology, as well as to policy makers, since facilitating the use of readily available transportation modes is primordial to maintaining social participation of seniors living in the community.

No description available.