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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

Nutritional and social environmental effects on parental care

Hopwood, Paul Edward January 2014 (has links)
Parental care is likely to evolve when benefits of care are greater than costs. Provision of parental care may buffer vulnerable offspring against unpredictable or hazardous environments permitting parents to breed in situations too hostile for unassisted juvenile survival. The nature of environmental unpredictability faced by parents and their offspring (e.g., availability of nutritional resources, breeding resources and/or the strength of competition) provides the ecological context in which costs and benefits of parental traits are defined. Therefore investigations about how the environment might shape parental traits ought not only to be conducted in the laboratory but also in a natural setting where unanticipated parameters may have profound effects on theoretical predictions. I conducted a series of manipulative experiments and observational studies in the laboratory and in the field using burying beetles, Nicrophorus vespilloides, to examine the effects of environmental variation on parental competitive ability, reproductive productivity, longevity and the expression of parental sex-role differences and alternative reproductive tactics. In these beetles a relative size advantage confers success in contests for scarce and vital breeding resources so a central prediction was that reproductive success would be positively correlated with body size. In contrast I found that reproductive performance was favoured over contest success when nutritional resources were delayed temporarily during a developmental window. Larger beetles do win contests for breeding-resources but the benefits of being large depend on the quality of the social environment experienced (i.e., the relative size of an opponent). In a naturalistic setting, smaller males avoided direct contests because they attracted proportionately more females and as a result their breeding associations were more often monogamous. This has potential benefits for females because they avoid female-female contests and brood parasitism. Variation in the nutritional environment provided by parents (the carcass size on which offspring are reared) directly influences body size creating a dynamism between the nutritional and social environments experienced by these beetles depending on their size, which has ramifications for their individual success and maintenance of alternative strategies in the population as a whole.
2

avpr1a microsatellite length does not affect parental care in male prairie voles (Microtus ochrogaster)

Kelley, Rebecca A. 02 May 2011 (has links)
No description available.
3

Female choice and paternal care in the fifteen-spined stickleback, Spinachia spinachia

Östlund-Nilsson, Sara January 2000 (has links)
<p>In the fifteen-spined stickleback, <i>Spinachia spinachia</i>, males provide females with direct benefits by fanning, cleaning and guarding the offspring. Males announce their parental skills through intense body shakes during courtship. Females preferred to mate with more intensely shaking males. As a result, females got better fathers for their offspring, as such males achieved a higher hatching success. Not only did male behavioural cues attract females, but males also used their nests as extrabodily ornaments. The nest is held together with shiny secretional threads consisting of a glycoprotein. Females chose to spawn in nests with more secretional threads. A likely reason for this is that the threads are metabolically costly for the male to produce and the amount of secretion indicates a male's nutritional status, which is of great importance as parental duties are energetically costly. Moreover, females preferred nests built high up in the vegetation, as such nests were safer from egg predators. Competition with other males for females favoured males building higher nests than did their neighbours, probably because females preferred high nests. Male-male interactions, such as sneaking and egg stealing, caused decreased paternity among males in nature as assessed by a microsatellite analysis. Males adjusted their paternal effort according to their previous investment in the brood, but not according to paternity. Thus, female choice is based on multiple cues and results in better paternal care. Males invest in courtship, male-male competition, nest construction and paternal care, the outcome determining their success in mate attraction.</p>
4

Female choice and paternal care in the fifteen-spined stickleback, Spinachia spinachia

Östlund-Nilsson, Sara January 2000 (has links)
In the fifteen-spined stickleback, Spinachia spinachia, males provide females with direct benefits by fanning, cleaning and guarding the offspring. Males announce their parental skills through intense body shakes during courtship. Females preferred to mate with more intensely shaking males. As a result, females got better fathers for their offspring, as such males achieved a higher hatching success. Not only did male behavioural cues attract females, but males also used their nests as extrabodily ornaments. The nest is held together with shiny secretional threads consisting of a glycoprotein. Females chose to spawn in nests with more secretional threads. A likely reason for this is that the threads are metabolically costly for the male to produce and the amount of secretion indicates a male's nutritional status, which is of great importance as parental duties are energetically costly. Moreover, females preferred nests built high up in the vegetation, as such nests were safer from egg predators. Competition with other males for females favoured males building higher nests than did their neighbours, probably because females preferred high nests. Male-male interactions, such as sneaking and egg stealing, caused decreased paternity among males in nature as assessed by a microsatellite analysis. Males adjusted their paternal effort according to their previous investment in the brood, but not according to paternity. Thus, female choice is based on multiple cues and results in better paternal care. Males invest in courtship, male-male competition, nest construction and paternal care, the outcome determining their success in mate attraction.
5

Rodičovské chování a jeho vztah k sociálnímu a reprodukčnímu systému u hrabošů \kur{(Microtus, Arvicolinae)} / Parental behaviour and its relationship to social and reproductive system in voles \kur{(Microtus, Arvicolinae)}

ELIÁŠOVÁ, Michaela January 2010 (has links)
I examined parental behaviour of three vole species, the brandt{\crq}s vole (Microtus brandti), the common vole (M. arvalis) and the levant vole (M. guentheri) in laboratory conditions. Monogamous and highly social Brandt{\crq}s voles displayed high levels of parental and paternal care. However, mostly promiscuous and solitary common voles also exhibited an intensive parental care. In contrast, polygynous and social levant voles displayed very low levels of parental care. Males of both latter species engaged in parental activities but spent less time in contact with pups then females. These findings suggest that intensive parental care may be connected rather with the high growth rate a slower postnatal development of the species than with social or reproductive system.
6

Sexual selection in <i>Pomatoschistus</i> – nests, sperm competition, and paternal care

Svensson, Ola January 2004 (has links)
<p>Sexual selection arises through variation in reproductive success. This thesis investigates different aspects important in sexual selection, namely nest building, sperm competition, paternity and paternal care, and their mutual interrelationships. In the studied species, the sand goby (<i>Pomatoschistus minutus</i>) and the common goby (<i>Pomatoschistus microps</i>), sperm competition did arise when small males, so called sneakers, sneaked into other males nests and released sperm. They seemed to use female behaviour as their prime cue for a sneaking opportunity. However, also nest-holders, both with and without eggs, were found to fertilize eggs in the nests of other males.</p><p>Clearly, nest-holding males tried to prevent other males from spreading their sperm in their nests, since they showed aggression towards such males. A nest building experiment indicated that the small nest-openings found in the sneaker male treatment were sexually selected through protection against sneaking or by female choice. Yet, no behavioural or genetical support for the hypothesis that the nest functions as a physical or visual defence, or that sneaker males prefer to sneak upon nests with wide nest-openings, were found in the other studies. Still, individual nest-holding males showed a higher mucus preparation effort inside the nest in the presence of a sneaker male than when alone. In close relatives, such mucus contains sperm, suggesting an importance in sperm competition. However, the mucus may also have pheromone and anti-bacterial functions and may constitute a mating effort, as found in other gobies. Both a behavioural and a mate choice experiment suggested that the males were not less eager to spawn in the presence of a sneaker male.</p><p>Sneak intrusion did not affect nest defence, fanning or filial cannibalism, nor had paternity an effect on filial cannibalism. This and various life history aspects, together with the fact that the parasitic male only fertilized a fraction of the clutches, would predict females to ignore sneaker males. This was also the case, as the presence of sneaker males was found not to affect female spawning decision. Still, several females spawned in two nests, which coincided with parasitic spawnings, suggesting a cost of disturbance for the females and thus a substantial cost to the nest-holding males in terms of lost mating success. However, females paid attention to other traits in their choice of mate since spawning was associated with sand volume of the nest, but not with nest-opening width. Also, female (but not male) courtship was correlated with partial clutch filial cannibalism, indicating that females are able to anticipate future male cannibalism.</p><p>In a partial correlation of nest opening, sand volume, male courtship display, displacement fanning and male size, a large number of traits were correlated both positively and negatively with regard to how we may expect them to be appreciated by females. For instance, males which fan well also build large nests or display intensely (but not both). Together with all the other results of this thesis, this shows the entangled selection pressures working on breeding animals, as well as the different male and female tactics employed to maximize their reproduction.</p>
7

Sexual selection in Pomatoschistus – nests, sperm competition, and paternal care

Svensson, Ola January 2004 (has links)
Sexual selection arises through variation in reproductive success. This thesis investigates different aspects important in sexual selection, namely nest building, sperm competition, paternity and paternal care, and their mutual interrelationships. In the studied species, the sand goby (Pomatoschistus minutus) and the common goby (Pomatoschistus microps), sperm competition did arise when small males, so called sneakers, sneaked into other males nests and released sperm. They seemed to use female behaviour as their prime cue for a sneaking opportunity. However, also nest-holders, both with and without eggs, were found to fertilize eggs in the nests of other males. Clearly, nest-holding males tried to prevent other males from spreading their sperm in their nests, since they showed aggression towards such males. A nest building experiment indicated that the small nest-openings found in the sneaker male treatment were sexually selected through protection against sneaking or by female choice. Yet, no behavioural or genetical support for the hypothesis that the nest functions as a physical or visual defence, or that sneaker males prefer to sneak upon nests with wide nest-openings, were found in the other studies. Still, individual nest-holding males showed a higher mucus preparation effort inside the nest in the presence of a sneaker male than when alone. In close relatives, such mucus contains sperm, suggesting an importance in sperm competition. However, the mucus may also have pheromone and anti-bacterial functions and may constitute a mating effort, as found in other gobies. Both a behavioural and a mate choice experiment suggested that the males were not less eager to spawn in the presence of a sneaker male. Sneak intrusion did not affect nest defence, fanning or filial cannibalism, nor had paternity an effect on filial cannibalism. This and various life history aspects, together with the fact that the parasitic male only fertilized a fraction of the clutches, would predict females to ignore sneaker males. This was also the case, as the presence of sneaker males was found not to affect female spawning decision. Still, several females spawned in two nests, which coincided with parasitic spawnings, suggesting a cost of disturbance for the females and thus a substantial cost to the nest-holding males in terms of lost mating success. However, females paid attention to other traits in their choice of mate since spawning was associated with sand volume of the nest, but not with nest-opening width. Also, female (but not male) courtship was correlated with partial clutch filial cannibalism, indicating that females are able to anticipate future male cannibalism. In a partial correlation of nest opening, sand volume, male courtship display, displacement fanning and male size, a large number of traits were correlated both positively and negatively with regard to how we may expect them to be appreciated by females. For instance, males which fan well also build large nests or display intensely (but not both). Together with all the other results of this thesis, this shows the entangled selection pressures working on breeding animals, as well as the different male and female tactics employed to maximize their reproduction.
8

Male Combat, Paternal Care, and the Evolution of Male Biased Sexual Size Dimorphism in the Emei Moustache Toad (Leptobrachium boringii)

Hudson, Cameron 06 September 2012 (has links)
I describe the natural history and reproductive behaviours of the Emei Moustache Toad (Leptobrachium boringii), testing the hypotheses that the species exhibits resource defense polygyny, and that combat, and paternal care lead to the evolution of male-biased sexual size dimorphism. In this study I document combat behaviour and paternal care for the first time in this species. Between February and March of 2011 and 2012, 26 female and 55 male L. boringii from Mount Emei UNESCO World Heritage Site, Sichuan, China, were observed throughout the breeding season. Prior to the breeding season, males grow 10-16 keratinized maxillary spines, which fall off once the season has ended. Throughout this time, males construct and defend aquatic nests where they produce advertisement calls to attract females. In a natural setting, I documented 14 cases involving a total of 22 males where males used their moustaches for aggressive interaction, and nest take over was observed on seven occasions. Despite my predictions, neither male body size nor body condition significantly affects the outcome of an aggressive interaction, though this may be representative of a low sample size. Males were also observed to possess injuries resulting from combat. Combat trials conducted in artificial nests demonstrated heightened aggression from resident males towards intruders. Genetic analysis using microsatellite markers revealed several cases of multiple paternity, both within nest and within clutch, indicating that some alternative male reproductive strategy, such as satellite behaviour is occurring. Larger males were observed to mate more frequently, and in multiple nests, suggesting that females are selecting for larger males, or that larger males are more capable of defending high quality territories. Males showed evidence of paternal care behaviours by remaining with the nests once females had left, moving throughout the nest cleaning, touching the eggs, and blowing bubbles into the centre of the doughnut-shaped egg masses. From this study I conclude that the male biased sexual size dimorphism in L. boringii is likely the result of both combat and paternal care behaviours creating a selection pressure on male body size.
9

Psychologické aspekty rodičovské péče o děti s poruchami autistického spektra / Psychological aspects of parental care for children with autism spectrum disorders

Felcmanová, Kateřina January 2017 (has links)
The thesis concerns the topic of parental care for children with autism spectrum disorder. In the theoretical part there are described the main areas in which the autistic spectrum disorders manifest and the description of particular disorders. Next chapter describes this issue from point of view of parental care, it describes the difficulty of the situation, the impact on the lives of parents and whole families, factors affecting the adaptation to the situation and its overall management. The qualitative study was chosen for the research. The sample is composed of 11 mothers of children with autism spectrum disorder. Data for study was collected by half-structured interviews and supplemented by Logo-test. The results of study describe the impact of care for a child with autism spectrum disorder to the lives of parents, emotions in different situations, stressing and supporting aspects of the situation, scarce factors and external factors which the most affect the situation of parents. It seems that the situation causes numerous of changes in the lives of parents and affects their values and attitude to life. Difficulty of the situation is perceived in the area of time managment, psychological, physical and financial area. In the same time there are strong supporting factors, mainly family and...
10

An investigation into the impact of childhood abuse and care-giver invalidation on psychological inflexibility in clinical and subclinical eating disorders

Tucknott, Maria January 2014 (has links)
As a whole, eating disorders have been characterised as having the following key features: a persistent over concern with body size and shape; and weight control behaviours such as fasting, exercise, and self-induced vomiting. However, there tends to be a blurred line between those that do and do not meet diagnostic thresholds as the level of psychological distress is comparably similar. This study examined whether psychological inflexibility (from an Acceptance and Commitment Therapy perspective) was associated with eating disorders and whether it mediated the relationship between childhood abuse and invalidation and eating disorders. This was considered to be important because high rates of abuse have consistently been found in this population, yet not everyone goes on to develop an eating disorder. In addition, the role of emotional abuse has been largely neglected. A clinical sample of 190 participants with a clinical or subclinical eating disorder were recruited from eating disorder charities and support forums; they completed a range of questionnaires measuring experiences of abuse and maternal/paternal emotional invalidation in childhood, current levels of cognitive fusion and experiential avoidance and current levels of eating pathology. The sample was split into three groups based on their Eating Disorder Risk Composite scores: elevated, typical and low clinical range. It was found that those in the elevated clinical range (most severe eating pathology) had the poorest emotional processing and significantly higher levels of psychological inflexibility, thought-shape-fusion, depression and anxiety than those in the low clinical range (least severe eating pathology). In terms of predicting current levels of eating pathology, three variables emerged as significant predictors: emotional processing, thought-shape fusion and depression. In terms of predicting current levels of psychological inflexibility, five variables emerged as significant predictors: childhood emotional abuse, emotional processing, thought-shape-fusion, depression and anxiety. The results add novel findings to the literature regarding the role of early experiences on the development of psychological inflexibility, and the role of psychological inflexibility in the maintenance of eating pathology and psychological distress. Clinical implications of these findings in relation to assessment, formulation, intervention and prevention are discussed.

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