Thesis (M.A.)--Georgia State University, 2007. / Title from file title page. Ian Fletcher, committee chair; Jared Poley, Hugh Hudson, committee members. Electronic text (110 [i.e. 105] p.) : digital, PDF file. Pages 18, 45, 76, 77 and 95 blank. Description based on contents viewed Jan. 16, 2008. Includes bibliographical references (p. 100-110).

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Microplitis croceipes (Hymenoptera: Braconidae) is an endoparasitoid and potential biological control agent of the tobacco budworm, Heliothis virescens (Lepidoptera: Noctuidae), an agricultural pest. The first objective of the following research was to amend current larval life history descriptions of M. croceipes. Larval head capsule width measurements were used to distinguish instar, and exuvium in abdominal cavities of post-egression hosts were indicative of a molt during parasitoid egression. Data revealed the larvae of M. croceipes pass through five instars, rather than three, as is indicated in the literature. The second objective was to investigate the suitability of potential artificial diets to be used in in vitro rearing of M. croceipes larvae. Three concentrations each of glucose, trehalose, and protein, as well as a combination diet (derived from initial diet trials) were tested. Growth, molting, and death were noted for each diet, and data indicated that diet had a significant effect for each performance measure (p = 0.0000, p < 0.0001, p < 0.0001, respectively). Data also indicated that trehalose and protein were more vital to larval parasitoid development (growth and molting) than was glucose, but no larvae were reared passed the second instar on an artificial diet. The final goals of the research were to evaluate the plausibility of rearing M. croceipes larvae to adulthood in vitro and to investigate post-egression host defensive behavior. Larvae were dissected from their hosts just prior to egression and placed in a cell culture plate in previously collected host hemolymph. Larvae were able to initiate pre-egression behavior in an in vitro environment, and a small percentage (6.67%) exhibited ecdysial splitting of the cuticle, however, no larvae were able to make the final molt in vitro. Post-egression hosts exhibited defensive behavior that may suggest they play a role in protecting pupating parasitoids. When the parasitoid exuvium was pulled from the egression wound in the host, hemolymph loss occurred and duration of the defensive behavior significantly decreased (p < 0.0001), indicating the exuvium acted to plug the egression wound, which prevented the host from bleeding to death and made it possible for the host to exhibit defensive behavior.

The typical intermediate morphology of hybrids may result in their failure to utilize the same niches as their parents. However, the fitness consequences of the potentially intermediate life-history traits of hybrids have been given less scientific attention. In this study I aimed to investigate how life-history divergence in parental species affects the relative fitness of nestling hybrids resulting from crosses between collared (Ficedula albicollis) and pied flycatchers (F. hypoleuca). Previous studies showed that collared flycatcher nestlings beg more intensively and grow faster under good conditions, but are less robust against the seasonal decline in food availability compared to pied flycatcher nestlings. This life-history divergence between the species allows regional coexistence. To investigate whether the life-history divergence in flycatchers influences the relative fitness of nestling hybrids, I cross-fostered hybrid nestlings in aviaries into the nests of conspecific pairs and compared their performance. I found that the hybrids displayed intermediate growth rates between collared and pied flycatchers across the season. There might therefore be environmental conditions when hybrids perform better than purebred offspring with respect to growth and survival.

This study uses a modified life history approach to gain deeper insights into the lived experiences of three teachers who became mothers while serving in Jamaica. This study was conceptualized as a result of my experiences as a teacher who became a mother. I was desirous of investigating if other teachers who became mothers in Jamaica experienced similar personal and professional transformation as a result of motherhood. The use of a life history approach necessitates an exploration of the wider historical, familial, socio-political, cultural, and economic factors influencing the lived experiences of participants and the meanings they give to their experiences. Dominant themes highlighted in the data include: the ideology that the overarching goal of education in Jamaica is for social mobility and an escape mechanism from poverty. Becoming a mother has resulted in participants taking greater levels of interest in the holistic development of students, rather than only emphasizing their academic development as they did prior to becoming mothers. Participants also developed more empathy for parents and closer collegial relationships when they became mothers. Participants’ relationships with administration were two-fold; on one hand they lobbied for improvements to their working conditions which may have a positive impact on their family life; while on the other hand, they also cared more about self-preservation in order to adequately meet the needs of their families. Motherhood also provided opportunities for participants to become more involved in various social groups in their communities. Various socio-political and economic challenges in Jamaica resulted in participants migrating to a Prairie city with their families. However, living in a multi-cultural society where they are racial minorities has presented its own challenges. Participants are negotiating the notion of home and being outsiders.

It has been acknowledged for some time that personal experience, relationship and emotional factors are important aspects of difficulties in learning to read and write; however there is still little research carried out in this area. This thesis explores the way in which eight adults make sense of their difficulties with reading and writing and identification of dyslexia; and their process of developing more positive self-perceptions and coping strategies. The study is guided by standpoint theory, with priority given to participants’ perceptions about difficulties in reading and writing rather than to academic and/or practitioner perspectives. Analysis of interviews is carried out through a life history methodology that identifies discourses of dyslexia in order to situate the way difficulties are understood and addressed. The discourses include four identified by Pollak (2005) and identification of six additional discourses of dyslexia that were present in both the literature review and at least half of the participant interviews. In the analysis, use of these discourses is mapped alongside the life story of each participant using the Model of Vocational Success (MVS) (Gerber et al. 1992) as a framework for classifying the development of positive self-perceptions and coping mechanisms. The participants’ life histories reveal that, without identification of dyslexia, difficulties with reading and writing are most often attributed by others such as teachers, peers and/or parents to low intelligence and/or lack of effort. Some participants rejected this understanding and others internalised it. Experience of ‘niche’ where the participant found themselves to be successful in a specific context best supported the development of positive self-perceptions and coping strategies before identification of dyslexia. Identification of dyslexia provided a means of making sense of difficulties, bolstered self-belief in intelligence, and initiated changes in support and personal motivation which, for the majority of participants, were notably beneficial. This PhD makes a number of unique contributions to knowledge about dyslexia, particularly through its prioritization of the voice of dyslexic people over professional voices. The identification of six additional discourses of dyslexia contributes to knowledge about the way difficulties with reading and writing can be understood and talked about, and exploration of how these discourses link to the MVS contributes knowledge about the advantages and disadvantages of these discourses to dyslexic people. The discourse ‘Hemispherist’ (Pollak 2005) was found to offer the most opportunity for dyslexic adults to develop positive self-perceptions and take constructive action to compensate for difficulties.

This study explores women’s experiences of sex with men. It is based on qualitative data collected from eighteen life history interviews. Such an approach provides means for examining women’s sexual experiences over time. The study finds that women give meaning to their sexual experiences through two main discursive representations: the passive, “proper” and sexually obliging girlfriend or wife, and the active and “sexually equal” woman. However, these representations do not capture the entirety of women’s sexual experiences. The life history analysis demonstrates that women are not simply inscribed by discourse. Rather, they are embodied beings actively engaged in pursuing sexual identities. Central to the process is a relationship between the practice of sex and self-reflexivity over time. Finally, the study demonstrates how the process of gaining sexual subjectivity is shaped by the material conditions of women’s lives. For instance, the praxeological circumstances of women’s class or race are powerful in recasting discourses of feminine sexuality, the meanings women ascribe to them, their access to broader sexual experiences, and the kinds of relationships they have with their male partners.

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Nearly 30 percent of the earth’s terrestrial surface is mountainous and despite representing a large proportion of the planet’s protected areas, the ecology of vertebrates in high elevation areas have received little attention from researchers and managers. I studied two subspecies of horned larks (Eremophila alpestris articola and E. a. strigata) that breed at high elevation and latitude in British Columbia, Canada and at low elevation and latitude in Washington, USA, respectively. I addressed the question of how the life history of alpine breeding songbirds differs from their low elevation conspecifics and showed that life history variation can be found among closely related groups. My results were consistent with other comparative demographic studies which suggest that alpine vertebrate populations tend to show survivor life history strategies when compared to their low elevation counterparts. In addition, population growth rates were stable for E. a. articola suggesting that this subspecies is well adapted to the challenges of breeding in alpine environments. E. a. strigata, however, is declining rapidly and the remaining breeding habitats in Washington do not support stable populations. I used demographic models to show that within reasonable ranges for each vital rate (fecundity, adult and juvenile survival), management actions that target a single rate independently are unlikely to result in stable or recovering populations and management actions that target multiple vital rates should be prioritized. Finally, to further investigate adaptations of E. a. articola to alpine environments I examined how they modify their incubation behavior in response to changes in ambient temperatures which were generally well outside the optimal temperature range for normal embryonic development. Females adjusted the amount of time spent incubating by varying the frequency rather than the duration of recesses. At low ambient temperatures they appeared to shift their investment toward the survival of their eggs by increasing the total time spent on the nest instead of taking longer or more frequent foraging bouts. Overall, the results of my study indicate that alpine populations of horned larks have life history traits and breeding behaviors that allow them to persist in these areas despite the challenging breeding conditions.

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