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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

Polygyny and childhood immunisation in Ethiopia: is there an association?

Sibiya, Johan Mduduzi January 2016 (has links)
Master's degree research report submitted to the Faculty of Humanities, in partial fulfilment of the requirements for the MA degree in Demography and Population Studies, 2016. / BACKGROUND: Childhood vaccination has proved to be one of the most successful and cost-effective health interventions in the world. However, one in eleven children in Ethiopia die before their fifth birthday, mostly as a result of vaccine preventable diseases and childhood immunisation coverage remains very low by any standard in the country. Little is known about the linkage between family structure and child health-seeking behaviour in Ethiopia where polygyny is common. This study examines the association between the type family structure with a particular interest in polygynous family structure and childhood immunisation among children aged 12 to 60 months in Ethiopia. METHODOLOGY: Data from the 2011 Ethiopia Demographic and Health Survey, containing a sample of 3 188 children aged 12-60 months were analysed and the vaccination history of children in relation to selected mother and child characteristics were examined. Bivariate tests as well as binary logistic regression models were used to examine the levels of childhood immunisation and the association between family structure and immunisation in Ethiopia. RESULTS: The data analysis revealed that 27% of Ethiopian children were immunised, 17.4% of children from polygynous households, and 27% of children in single-parent and monogamous households were immunised. Overall family structure was not found to be significantly associated with childhood immunisation. Geographical region, poverty status, mother’s age, parity, antenatal care and mother’s place of delivery were found to be significant determinants of child immunisation in Ethiopia. CONCLUSION: Complete immunisation coverage among children aged 12-60 months remains very low by any standard in Ethiopia. Findings show that although a polygynous family structure is not a significant determinant of childhood immunisation it has a positive effect on it. Improved awareness of child immunisation services among mothers would greatly increase immunisation coverage. / GR 2017
2

Female intrasexual reproductive competition in the facultatively polygynous song sparrow

Kleiber, Danika Lynn 11 1900 (has links)
Reproductive competition among females is an under-studied aspect of behavioural ecology. In species where males provide non-sharable resources that enhance individual and offspring fitness, such as feeding young, intrasexual conflict among females should be expected. My thesis examined reproductive competition among female song sparrows by estimating the reproductive costs of losing male care and behavioural strategies females employed to avoid the loss of male care. I used a long-term study of song sparrows, a facultatively polygynous passerine, on Mandarte Island, British Columbia Canada, to examine the potential reproductive and survival costs that polygyny might have on females. I found that polygynous females without male care experienced lower nest and lifetime reproductive success than polygynous females with male care. In contrast, female status within polygynous groups had no impact on overwinter survival. Three strategies that females might use to avoid polygyny or ensure access to male parental care while in polygyny include 1) intrasexual aggression to deter secondary females from settling, 2) infanticide of primary female’s nest by secondary females to improve nesting status or 3) nest timing to either increase the comparative worth of the nest through synchrony, or eliminate competition for male care through asynchrony. Using a mount presentation experiment I found that resident females reacted as predicted if intrasexual aggressive behaviour was used to deter secondary female settlement and ensure male parental care. Over 18 years when polygyny occurred in the population, I found evidence that the presence of secondary females was correlated with a rise in the nest failure rate of primary females, but I found no evidence that polygynous females used nest timing strategies to influence access to male care. Overall, my results suggest that female song sparrows use aggressive behaviours to reduce secondary female settlement, and within polygynous groups secondary females may use infanticide to advance their status. Despite the existence of female strategies to circumvent the loss of fitness due to polygynous mating, polygyny still occurred regularly in the population. This observation suggests that the strategies described above are often not effective, or that their costs outweigh the potential gains to individual fitness.
3

Female intrasexual reproductive competition in the facultatively polygynous song sparrow

Kleiber, Danika Lynn 11 1900 (has links)
Reproductive competition among females is an under-studied aspect of behavioural ecology. In species where males provide non-sharable resources that enhance individual and offspring fitness, such as feeding young, intrasexual conflict among females should be expected. My thesis examined reproductive competition among female song sparrows by estimating the reproductive costs of losing male care and behavioural strategies females employed to avoid the loss of male care. I used a long-term study of song sparrows, a facultatively polygynous passerine, on Mandarte Island, British Columbia Canada, to examine the potential reproductive and survival costs that polygyny might have on females. I found that polygynous females without male care experienced lower nest and lifetime reproductive success than polygynous females with male care. In contrast, female status within polygynous groups had no impact on overwinter survival. Three strategies that females might use to avoid polygyny or ensure access to male parental care while in polygyny include 1) intrasexual aggression to deter secondary females from settling, 2) infanticide of primary female’s nest by secondary females to improve nesting status or 3) nest timing to either increase the comparative worth of the nest through synchrony, or eliminate competition for male care through asynchrony. Using a mount presentation experiment I found that resident females reacted as predicted if intrasexual aggressive behaviour was used to deter secondary female settlement and ensure male parental care. Over 18 years when polygyny occurred in the population, I found evidence that the presence of secondary females was correlated with a rise in the nest failure rate of primary females, but I found no evidence that polygynous females used nest timing strategies to influence access to male care. Overall, my results suggest that female song sparrows use aggressive behaviours to reduce secondary female settlement, and within polygynous groups secondary females may use infanticide to advance their status. Despite the existence of female strategies to circumvent the loss of fitness due to polygynous mating, polygyny still occurred regularly in the population. This observation suggests that the strategies described above are often not effective, or that their costs outweigh the potential gains to individual fitness.
4

Female intrasexual reproductive competition in the facultatively polygynous song sparrow

Kleiber, Danika Lynn 11 1900 (has links)
Reproductive competition among females is an under-studied aspect of behavioural ecology. In species where males provide non-sharable resources that enhance individual and offspring fitness, such as feeding young, intrasexual conflict among females should be expected. My thesis examined reproductive competition among female song sparrows by estimating the reproductive costs of losing male care and behavioural strategies females employed to avoid the loss of male care. I used a long-term study of song sparrows, a facultatively polygynous passerine, on Mandarte Island, British Columbia Canada, to examine the potential reproductive and survival costs that polygyny might have on females. I found that polygynous females without male care experienced lower nest and lifetime reproductive success than polygynous females with male care. In contrast, female status within polygynous groups had no impact on overwinter survival. Three strategies that females might use to avoid polygyny or ensure access to male parental care while in polygyny include 1) intrasexual aggression to deter secondary females from settling, 2) infanticide of primary female’s nest by secondary females to improve nesting status or 3) nest timing to either increase the comparative worth of the nest through synchrony, or eliminate competition for male care through asynchrony. Using a mount presentation experiment I found that resident females reacted as predicted if intrasexual aggressive behaviour was used to deter secondary female settlement and ensure male parental care. Over 18 years when polygyny occurred in the population, I found evidence that the presence of secondary females was correlated with a rise in the nest failure rate of primary females, but I found no evidence that polygynous females used nest timing strategies to influence access to male care. Overall, my results suggest that female song sparrows use aggressive behaviours to reduce secondary female settlement, and within polygynous groups secondary females may use infanticide to advance their status. Despite the existence of female strategies to circumvent the loss of fitness due to polygynous mating, polygyny still occurred regularly in the population. This observation suggests that the strategies described above are often not effective, or that their costs outweigh the potential gains to individual fitness. / Forestry, Faculty of / Graduate
5

Are United States Anti-Polygamy Laws Efficient?

Wirtshafter, Jasper F. 13 May 2016 (has links)
No description available.
6

The use of personal names in respect of the living-dead within traditional polygynous families in Kwamambulu, Kranskop.

Ngidi, Evangeline Bonisiwe. January 2012 (has links)
The thesis underpinning this dissertation is based on the Zulu people’s belief in the living-dead and the fact that the latter control the lives of their living descendants. The living descendants use names to express their dissatisfaction with one another. The families perform rituals to appease the living-dead. The living-dead are perceived as guardian angels who are closer to God. They are believed to be able to reward good behavior and reprimand those who are not behaving in an acceptable manner. Names, as Bhengu (1975:52) states, connect people to their living-dead. It is therefore important that this relationship with the living-dead is maintained. Friction is always going to be a problem in polygynous families. Avoiding confrontation is important to people who want to appease their living-dead, who control their lives. Personal names act as a deterrent to angering the living-dead. In a situation where getting even is not an option, opting for a name to voice your disapproval is the easy way out. Names become communication channels between members of the family and the community at large. This study is done from an ethnographic perspective with an attempt to fully describe a variety of aspects of a cultural group to enhance understanding of the people being studied. Spradley (1980:3) states that “The essential core of ethnography is the concern with the meaning of actions and events to the people we seek to understand”. This understanding may be seen as the basis of the method; through ethnographic study, the researcher comes to comprehend, through detailed observation, the existences of peoples and their cultures. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
7

Reproductive Characteristics, Multiple Paternity and Mating System in a Central Florida Population of the Gopher Tortoise, <em>Gopherus polyphemus</em>

Colson-Moon, Jamie Colleen 10 July 2003 (has links)
I studied the reproductive characteristics and mating systems of a central Florida population of gopher tortoises (Gopherus polyphemus). Using x-radiography, females were monitored for stage in egg-shelling and clutch size. Eggs began to appear on x-ray photographs in the first week of May in both 2001 and 2002; however, fully shelled eggs were not found before the end of May. In total 55% of the females x-rayed were gravid. Clutch sizes ranged from 4-12 with a mean of 7.29, with a mean clutch mass of 40.9 g. Clutch size increased with an increase in mean carapace length and mean plastron length. Mean clutch mass also increased with mean carapace length of females. Hatchlings began to emerge in late August, with incubation times ranging from 83 to 96 days. 50% of the eggs hatched, with 16.2% of the eggs showing no signs of development when opened. Hatchling mass averaged 30.7 g and was positively correlated with egg mass. DNA was extracted from blood samples obtained from females and their offspring, and from the sexually mature males in the population. Nine microsatellite loci were amplified and genotypes constructed for each individual. There is evidence for promiscuous mating in gopher tortoises. Multiple paternity was detected in two of the seven clutches (28.6 %). In the clutches with multiple fathers, fertilization was highly skewed to one male, with primary male fertilizing over 70% of the clutch. Females with multiple-sired clutches were significantly smaller than females with single-sired clutches. Among the clutches assayed only one male fertilized more than one clutch, indicating that insemination of females is evenly spread among males of similar sizes. However, males assigned as fathers were significantly larger than other sampled males which may mean that larger males have an advantage in fertilization of clutches. Conservation efforts should consider the impact of the mating system on reproduction in a population, and the possible impact of the relocation of larger males on recipient populations.
8

Evolutions des stratégies reproductrices au sein du genre Plagiolepis (Hymenoptera: Formicidae)

Thurin, Nicolas 18 June 2010 (has links)
Selon la théorie de la sélection de la parentèle, les individus peuvent transmettre des copies de leurs gènes à la génération suivante sans accéder eux-mêmes à la reproduction, mais en aidant des apparentés à augmenter leur propre succès reproductif. Ce concept reste aujourd'hui l'explication la plus probable pour justifier l'évolution de l’altruisme de reproduction dans le règne animal. Les coefficients de corrélations génétiques entre les membres d’un groupe ont une importance capitale, puisqu'ils influencent directement les bénéfices génétiques indirects associés au comportement altruiste. Trois principaux facteurs sont cependant connus pour influencer profondément l'architecture des sociétés: (i) le nombre de reines présentes dans un nid (polygynie), (ii) le nombre d'accouplements des reines (polyandrie), et (iii) l’accouplement entre apparentés (consanguinité). Nous avons étudié les stratégies de reproduction de cinq espèces de fourmis du genre Plagiolepis. Nous avons d’abord déterminé l’origine endogène des signaux de reconnaissance responsables de la fermeture des sociétés (I). Nous avons également identifié les causes proximales de la forte consanguinité observée chez P. pygmaea : une éviction par les ouvrières des mâles étrangers tentant de s’introduire dans leur société et une préférence des femelles vierges à s’accoupler avec des mâles apparentés (II). A l’aide de marqueurs génétiques, nous avons estimé le degré de polygynie, le taux de polyandrie des reines, et le niveau de consanguinité pour quatre espèces libres : P. pygmaea, P. taurica, P. schmitzii et P. maura (III; IV). Enfin, nous avons testé l’hypothèse d’une réversion du nombre d’accouplements vers la monandrie chez les espèces parasites, au travers de P. xene. (V).
9

Polygyny and gender : narratives of professional Zulu women in peri-urban areas of contemporary KwaZulu-Natal.

Mkhize, Zamambo Valentine. January 2011 (has links)
Polygyny has been defended by some men in terms of ‘tradition and culture’ but a cursory observation suggests that it is currently being embraced even amongst women. It seems that some women are willing to allow a husband to take a second wife and even in arranged marriages some women seem content to enter into a polygynous union because they will be answering the call of duty. This study seeks to explore why even some middle-class educated women enter polygynous marriages. The study is different than the previous studies conducted because it focused on women who were educated and had employment that made them financially independent. Previous studies focused on poor rural women who had no better option but to marry into polygynous marriages for a better life because in the past it was only wealthy men who could afford to support more than one family and unfortunately that is not the case in today’s society, now it is just any man who wants to ‘elevate his manhood’ by having more than one wife but who he cannot support. The findings showed women entered such unions for numerous reasons such as love, family and societal pressures as well as desperation to have a higher social standing in the community than a single woman. / Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2011.
10

Causes and Consequences of Queen-Number Variation in the California Harvester Ant Pogonomyrmex californicus.

January 2011 (has links)
abstract: Social insect colonies exhibit striking diversity in social organization. Included in this overwhelming variation in structure are differences in colony queen number. The number of queens per colony varies both intra- and interspecifically and has major impacts on the social dynamics of a colony and the fitness of its members. To understand the evolutionary transition from single to multi-queen colonies, I examined a species which exhibits variation both in mode of colony founding and in the queen number of mature colonies. The California harvester ant Pogonomyrmex californicus exhibits both variation in the number of queens that begin a colony (metrosis) and in the number of queens in adult colonies (gyny). Throughout most of its range, colonies begin with one queen (haplometrosis) but in some populations multiple queens cooperate to initiate colonies (pleometrosis). I present results that confirm co-foundresses are unrelated. I also map the geographic occurrence of pleometrotic populations and show that the phenomenon appears to be localized in southern California and Northern Baja California. Additionally, I provide genetic evidence that pleometrosis leads to primary polygyny (polygyny developing from pleometrosis) a phenomenon which has received little attention and is poorly understood. Phylogenetic and haplotype analyses utilizing mitochondrial markers reveal that populations of both behavioral types in California are closely related and have low mitochondrial diversity. Nuclear markers however, indicate strong barriers to gene flow between focal populations. I also show that intrinsic differences in queen behavior lead to the two types of populations observed. Even though populations exhibit strong tendencies on average toward haplo- or pleometrosis, within population variation exists among queens for behaviors relevant to metrosis and gyny. These results are important in understanding the dynamics and evolutionary history of a distinct form of cooperation among unrelated social insects. They also help to understand the dynamics of intraspecific variation and the conflicting forces of local adaptation and gene flow. / Dissertation/Thesis / Ph.D. Biology 2011

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