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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Are you a boy or a girl? Contesting the uncontested: intersex and genders

Kerry, Stephen Craig January 2005 (has links)
Research Doctorate - Doctor of Philosophy (PhD) / One question that is perhaps most familiar in contemporary western societies is “is it a boy or a girl?” This question goes uncontested unless a child is born with ambiguous genitalia. The medical responses to these births have recently undergone considerable attention and criticism from within the medical profession, from parents, but most loudly from the individuals themselves. In contemporary discourses these individuals are referred to by and large as intersex. The burgeoning intersex movement has coalesced around a shared lived experience of trauma brought about in no small way by the invasive procedures of medical management in its attempts to diagnose, treat and cure. These procedures leave intersex individuals with feelings of isolation and abuse and that they have been lied to and misinformed. A ‘culture of silence’ has been created whereby not only has the incidence of intersex been vastly underestimated, but also the psychological, social and physical ramifications have been omitted from medical, patient and broader social discourses. While intersex individuals cite their own experiences as evidence of these ramifications, the medical profession has been largely unresponsive. Aside from the demand for more information, counselling and a change in the medical management of intersex, there are broader ramifications of intersex within society, notably a conceptualisation of sex, gender and sexuality. While these aspects are secondary issues for the intersex movement its presence and its significance cannot be understated. This study takes note of the significant issues pertinent to the intersex movement and employs a comparative analysis of the lived experiences of Intersex Australians and Americans. Further, this project investigates the historical and cross-cultural evidence of intersex, the way in which medical discourses dominate twentieth and twenty-first century conceptualisations and how the intersex movement itself was formed in the last decade.
2

Mating behaviour, epibiotic growth, and the effect of salinity on grooming activity in the hermaphroditic shrimp Lysmata wurdemanni

Giri, Tuhin 30 September 2004 (has links)
Many species of caridean shrimp are protandrous hermaphrodites, maturing initially as males but developing into females as they age and grow. A unique sexual system was recently discovered in the peppermint shrimp, Lysmata wurdemanni. In this species, individuals are initially male, but become simultaneous functional hermaphrodites over time. As in most caridean shrimp, L. wurdemanni can mate as a male during the intermoult period, but can reproduce through female function for only a short period after moulting. Ecdysis does not occur en masse in this species, and thus the operational sex ratio found in populations of L. wurdemanni is extremely male-biased. Sexual selection theory suggests that these conditions will result in increased competition for access to mates. Evolutionary pressures should therefore have selected for mechanisms that permit individuals to quickly identify and locate potential mating partners. L. wurdemanni were exposed to chemical stimuli collected from recently moulted conspecifics of varying reproductive condition. Test animals were able to distinguish among the different conditions, and physically manipulated only the plastic nozzle used to pump solutions collected from shrimp with ovaries filled with vitellogenic oocytes. It was subsequently hypothesized that methyl farnesoate, a hormone associated with ovarian maturation in crustaceans, might be a key component of sex pheromones used by L. wurdemanni. However, a series of methyl farnesoate concentrations did not elicit responses, indicating this species does not use this hormone alone when determining reproductive condition. Reproductive behaviour in L. wurdemanni was observed to differ both before and after copulation, as well as with increasing population density. Intermoult individuals were more likely to approach, follow and remain in the vicinity of a near-moult shrimp before mating could occur, and under high density conditions. The near-moult shrimp approached conspecifics only under low density conditions, and performed rapid escape behaviours only after copulation had occurred. The unusual occurrence of epibiota upon L. wurdemanni was described, and the location, size and age of barnacles quantified. The effect of salinity upon grooming activities was tested. Results indicated that carapace grooming was depressed at low salinities, and could account for the considerable epibiota found in this region.
3

Separating the sexes : sexual conflict and how to resolve it

Cirulis, Aivars January 2016 (has links)
During the evolution of sex, different sexual conflicts arise. Sexual conflicts reduce fitness of the opposite sex. That is why several mechanisms have evolved to resolve them, which leads to rapid and unpredictable co-evolution of male and female traits involved in reproduction. This rapid co-evolution of male and female reproductive traits driven by sexual conflict can further lead to reproductive isolation resulting in speciation.             I used the hermaphroditic fungus Neurospora crassa, which has two mating types, as a model organism. Mating types are proxy to sex, because both are needed for sexual reproduction, but they are not limited to either sex role. However by using male pheromone knock-out lines, I created an evolutionary setup, where either mating type is forced to adapt to its restricted sex role. After 21 sexual generations of adaptive co-evolution, I tested if mating types had adapted to the assigned sex by measuring fitness (production of sexual spores called ascospores). I used three evolutionary setups (lines): Δccg4 lines, where mat A is female and mat a is adapted to the male role, Δmfa1 lines, where conversely mat A is adapted to the male role and mat a is female, and wild-type lines used as controls, where both mating types have maintained and adapted to both sex roles. And discovered one Δccg4 line, which indeed adapted to the newly assigned sex roles. At generation 15 and 21 I obtained mixed results for the presence of sexual conflict by correlating male and female fitness in hermaphroditic partner mat a in this line, however I found a sexual conflict also in the asexual growth, where male role is associated with increased, but female role with decreased mycelium growth rate. This work will further allow to study genomic mechanisms underlying this adaptation.
4

La figure de l'androgyne dans les romans de Tahar Ben Jelloun : L'enfant de sable et La nuit sacrée

El Bousouni, Abdelmounym January 2006 (has links) (PDF)
Le sujet du présent mémoire porte sur la figure de l'androgyne dans le diptyque de Tahar Ben Jelloun, L'enfant de sable et La nuit sacrée. La singularité de l'androgyne en question émane de sa configuration synchronique alliant les deux pôles sexuels, soit le masculin et le féminin, dans un même corps. L'énoncé narratif est construit autour de ce schème bisexuel qui alterne les deux paradigmes antithétiques de l'androgynie: le premier, profane, est articulé sur une conception négative marquée par la confusion entre les deux pôles sexuels. Ce cas de figure est représenté par Ahmed-Zahra. Le second présente une vision subliminale articulée sur la fusion harmonieuse entre l'élément féminin et l'élément masculin, inspirée par la mystique soufie qui prône une sorte d'eschatologie de l'amour. La relation Zahra-Le Consul est représentative de cette configuration. Au travers de cette double construction se profile une esthétique romanesque impulsée par l'intertexte mystique. De surcroît, la figure de l'androgyne, en tant que lieu du conflit entre les sexes qui l'habitent, offre à l'auteur l'occasion d'investir le champ de l'antagonisme social intersexuel marqué par la domination masculine. L'androgyne s'avère ainsi un corps spéculaire. Afin de rendre compte des enjeux esthétiques et idéologiques de la dite figure dans le diptyque de Ben Jelloun, le présent travail se divise en trois chapitres. Dans le premier chapitre, il sera question de l'androgynie comme représentation mythique. On exposera la dimension sacrée du mythe de l'androgyne dans les cultures dites archaïques puis dans l'antiquité. On étudiera également la dimension universelle et archétypique du mythe. Enfin, on exposera le double rapport antithétique que les anciens établissent entre androgyne sacré et androgyne profane. Dans le second chapitre, on analysera le passage du mythe en question dans la philosophie, inauguré par Le Banquet de Platon. On s'arrêtera également au passage de l'androgyne du mythe platonicien à l'herméneutique mystique et de cette dernière à la littérature occidentale et ce, à la moitié du XIXe siècle. A partir de la combinaison entre l'androgyne platonicien et l'Adam biblique, Michel Tournier, dont on analysera brièvement le roman, Le Roi des Aulnes, forge la figure syncrétique de l'Adam phorique, figure androgynique par excellence que tente de réactualiser le personnage principal, Abel Tiffauges. Dans le troisième chapitre, on analysera toutes les données théoriques autour de l'androgynie et leur application au diptyque de Ben Jelloun. On verra que le roman embrasse les deux aspects de l'expérience androgynique, soit l'androgyne sacré et l'androgyne profane. De plus on approchera le diptyque à la lumière du référent mystique qui impulse une esthétique scripturaire articulée sur le thème de la quête. Enfin, au travers de la figure de l'androgyne se dessine un discours de la stigmatisation qui met en procès le despotisme masculin. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Androgyne, Archétype, Mythe, Soufisme, Corps, Ben Jelloun, L'enfant de sable, La nuit sacrée, Littérature marocaine.
5

A Psychological Investigation of Seven Hermaphroditic Children

Kranz, Peter Lewis 01 May 1969 (has links)
An in-depth personality and intellectual evaluation of a group of hermaphroditic children residing in the state of Oklahoma was undertaken in this study. The following techniques were utilized in order to extensively study the impact of this anomaly on the families of these children: psychological tests, parental interviews by a social worker, and diagnostic play interviews conducted by the investigator. It was the purpose of this study to examine the psychological impact of sexual ambiguity on the child and his parents. There were no significant differences between the two groups on any of the tests given. This may be attributed to the small sample size. Certain trends seemed apparent but they could also have been effected by the limited sample. These trends were: The play activities and interests of the children appeared to be age appropriate in relation to their socio-economic background. There was, however, a tendency on the part of the older children to prefer activities which were more masculine than feminine in nature. Few close heterosexual relationships were mentioned by the subjects. Four of the children stated that they would like to make nursing a career. The three older children seemed more aware of their medical condition than the younger subjects and were aware that they were different in some ways from the normal population. The three older subjects seemed more affected by the anomaly than the younger ones and were more sensitive to it and to relationships with others. As a group there seemed to be nothing unusual in their typical daily routine except for the medication which had to be taken regularly. The children seemed to be self-conscious and reluctant in describing themselves to the investigator particularly as it pertained to their medical anomaly. An optimistic philosophy of life was expressed by the subjects in which emphasis was placed upon religious values, a desire to help others, and an ambition to live the golden rule. In the children's explanations of how they would like to be different, reference was made to their medical condition. In no case did the birth of a hermaphroditic child into a family inhibit future conceptions and subsequent births. All families but one felt that they needed greater medical understanding and guidance with regard to the anomaly as well as with proper management of the condition once it had been diagnosed. It was felt by four groups of parents that desirable sex change should occur in the child as early as possible, preferably before three years of age. All families tended to keep the sexual anomaly issue closed and limited to their immediate family. It appeared that socio-economic factors made little difference in the parents' general concern for their child and its adequate adjustment to the environment. Accessible and comprehensible medical information about hermaphroditism is almost unavailable to those desiring it because of the current infrequency of incidence and variations in condition.
6

Fantasizing Hermaphroditism: Two-Sexed Metaphors in Nineteenth-Century American Literature and Culture

Lewis-Turner, Jessica Lindsay January 2017 (has links)
In nineteenth-century medicine, it was generally agreed that “true hermaphroditism,” or the equal combination of male and female sexual characteristics in one body, was impossible in humans. Yet true hermaphroditism remained a significant presence in both fictional and non-fictional texts. Much of the scholarly literature is on the history of hermaphroditism as a history of intersexuality. Fantasizing Hermaphroditism: Two-Sexed Metaphors in Nineteenth-Century American Literature and Culture is a study of both hermaphroditism and the hermaphrodite as a fantasy. My approach is a combination of historicization and close reading. The chapters are in chronological order, and each chapter is centered on a single text. Chapter 1 addresses Julia Ward Howe’s fictional manuscript, The Hermaphrodite; Chapter 2, S.H. Harris’ case narrative on “A Case of Doubtful Sex”; Chapter 3, James Kiernan’s theoretical treatise on “Responsibility in Sexual Perversion”; and Chapter 4, a memoir by an author who went by the names Ralph Werther and Earl Lind, titled Autobiography of an Androgyne. I begin with the broader cultural moment of the text’s writing, and then explore the text’s language and structure in greater depth. This range of texts demonstrates that the hermaphrodite was a fantasy for nineteenth century authors, described as an impossibility but inspiring very real fear and pleasure. The language that they—and we—use in fantasies about the unreal hermaphrodite can help us to unpack these anxieties and desires around marriage, the body, race, and the definition of the individual. / English
7

Establishing the mangrove killifish, Kryptolebias marmoratus, as a model species for developmental biology

Mourabit, Sulayman January 2012 (has links)
The mangrove killifish, Kryptolebias marmoratus, has the potential of becoming a strong model organism for a range of biological disciplines thanks to its ability to self-fertilise, a process only known to occur in invertebrate animals until its discovery. Selfing, a natural occurrence in this species, has lead to the formation of clonal lineages composed of highly homozygous individuals. The aim of this thesis was to further establish K. marmoratus in the field of developmental biology by providing an information infrastructure to help advance research on this peculiar animal and further promote its place in the pantheon of model organisms. To do so, I first set out to standardise K. marmoratus embryology by providing defined developmental stages with clear visual representations of key embryonic structures. This staging series is an essential tool that will ensure repeatability and consistency within and across different laboratories. Secondly, I examined several techniques for embryonic manipulation and for imaging that can be used in an array of experimental designs. Using these techniques I demonstrated microinjection of embryos by monitoring the yolk syncytial layer and its nuclei, and time-lapse analyses of the yolk surface during embryonic development. Finally, I applied the knowledge gained from my first two studies and examined Bmp signalling in K. marmoratus embryos and its influence on body patterning. By inhibiting this pathway, I found a new phenotype characterised by an extremely short and split body axis. These data highlighted the importance of studying known signalling pathways in unknown organisms as species-specific differences may improve our understanding of fundamental developmental processes. This thesis demonstrates that with its easily obtainable and manipulated embryos, K. marmoratus can be used for embryological research in the same light as other model organisms such as zebrafish or medaka. The rising amount of information on mangrove killifish will help further take advantage of this unique and intriguing species, and supports the use of this hermaphroditic vertebrate as a strong comparative model in developmental biology.
8

Age, Growth, and Reproduction of Calamus proridens the Littlehead Porgy, from the Northeast Gulf of Mexico

Tyler-Jedlund, Amanda J 29 May 2009 (has links)
A total of 1814 Calamus proridens ranging from 76 mm - 361mm fork length (FL) were collected and processed along the central and northwest coasts of Florida between 2000 and 2007 to determine size, sex, age, and reproductive condition. Females ranged from 76-297 mm FL (mean FL=156 mm, n=1420), males ranged from 141-361 mm FL (mean FL=244 mm, n=297), and transitionals ranged from 131-307 mm FL (mean FL=207 mm, n=42). Sex ratios sorted by length class, age, and overall were significantly different from the 1:1 ratio for gonochoristic species (P is less than 0.0001). Sagittal otoliths (sectioned and whole) from 1438 C. proridens were used to determine age. Marginal increment analysis suggested that a single annulus is formed each year in the spring. Ages ranged from 0 to 10 years with 88% of the fish being between 0 and 4 years. Females ranged in age between 0 and 6 years, while males ranged between 1 and 10 years. Growth was rapid in the first two years and then began to slow down. The von Bertalanffy growth model fitted to all observed data was L(t)=306[1-e-0.254(t+1.69)]. The data were further broken down into central and southern strata and the von Bertalanffy growth model showed that fish in the central region grow larger than those in the southern region. Histological analysis confirmed that C. proridens are protogynous hermaphrodites with delimited type gonads. Estimates indicated that 50% of the females in the sample had transitioned into males by age 4 and a FL of 231 mm. Calamus proridens mature at a small size; 50% of the samples were mature by 132 mm and within the first year. The samples obtained indicated that the peak spawning season is in the spring. The presence of hydrated oocytes and post ovulatory follicles in the same ovary suggests that they are multiple spawners.
9

Reproduction in the Hermaphrodite Aeolidiella glauca - A Tale of Two Sexes

Karlsson, Anna January 2001 (has links)
<p>This thesis focuses on reproduction in a simultaneous hermaphrodite with internal fertilization; the nudibranch <i>Aeolidiella glauca</i>. Unlike most other nudibranchs, where copulation is the rule, <i>A</i>. <i>glauca</i> was found to transfer sperm via external spermatophores that were attached to the partner's back. Despite elaborate courtship the actual spermatophore transfer, which always involved two animals only, was of short duration. In most matings (88%) spermatophores were reciprocally exchanged. </p><p><i>A. glauca</i> was further found to be very promiscuous. During mating and sperm transfer the receiver exerts considerable control over sperm, and manipulative behaviours designed to increase the donor's reproductive success are thus likely to have evolved. An example of such manipulative behaviour may be <i>A. glauca's</i><b> </b>unique spermatophore avoidance behaviour. I found that slugs carrying a sign of previous mating activity, i.e. a spermatophore, were discriminated against in a situation where mate choice was possible. The presence of spermatophores was further found to reduce slugs' ability to interrupt matings, and displace other slugs. Body size, however, had no direct effect on displacement in <i>A. glauca</i> as small slugs interrupted matings as successfully as large ones. Furthermore, pair formation and mating were found to be random with respect to size. This was true also for pairs formed in the field. </p><p>In addition to mate choice hermaphrodites may increase their reproductive success by differential sex allocation. I tested whether differing mate encounter rates had any effects on allocation to male and female function in <i>A. glauca</i>. Slugs with more mating opportunities mated more, and had higher proportional spermatophore production that others. As predicted they also laid significantly fewer eggs than slugs presented with partners less often.</p>
10

Reproduction in the Hermaphrodite Aeolidiella glauca - A Tale of Two Sexes

Karlsson, Anna January 2001 (has links)
This thesis focuses on reproduction in a simultaneous hermaphrodite with internal fertilization; the nudibranch Aeolidiella glauca. Unlike most other nudibranchs, where copulation is the rule, A. glauca was found to transfer sperm via external spermatophores that were attached to the partner's back. Despite elaborate courtship the actual spermatophore transfer, which always involved two animals only, was of short duration. In most matings (88%) spermatophores were reciprocally exchanged. A. glauca was further found to be very promiscuous. During mating and sperm transfer the receiver exerts considerable control over sperm, and manipulative behaviours designed to increase the donor's reproductive success are thus likely to have evolved. An example of such manipulative behaviour may be A. glauca's<b> </b>unique spermatophore avoidance behaviour. I found that slugs carrying a sign of previous mating activity, i.e. a spermatophore, were discriminated against in a situation where mate choice was possible. The presence of spermatophores was further found to reduce slugs' ability to interrupt matings, and displace other slugs. Body size, however, had no direct effect on displacement in A. glauca as small slugs interrupted matings as successfully as large ones. Furthermore, pair formation and mating were found to be random with respect to size. This was true also for pairs formed in the field. In addition to mate choice hermaphrodites may increase their reproductive success by differential sex allocation. I tested whether differing mate encounter rates had any effects on allocation to male and female function in A. glauca. Slugs with more mating opportunities mated more, and had higher proportional spermatophore production that others. As predicted they also laid significantly fewer eggs than slugs presented with partners less often.

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