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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.
61

Testing For Indirect Benefits Of Polyandry In The Florida Green Turtle

Long, Christopher 01 January 2013 (has links)
Behavioral studies in the green turtle (Chelonia mydas) have indicated that promiscuous mating is commonplace. Though it has been shown that there is much variation in the rate of polyandry (females mating with multiple males), the drivers behind polyandry in this species are unknown. It has been speculated, but never demonstrated, that indirect benefits (fitness benefits resulting from offspring genetic diversity) play a role. However, previous tests of this hypothesis have limited scope of inference due to lack of environmental control. In this thesis, I attempted to study the indirect benefits of polyandry in Archie Carr National Wildlife Refuge (ACNWR) green turtles, limiting environmental variation by selecting nests over two week periods in a small subset of the ACNWR. Through the use of highly polymorphic microsatellite markers, I show that 85.7% of ACNWR green turtle females mate with multiple males, the highest rate yet reported for green turtles. I was successful in limiting environmental variation; however, I was unable to make comparisons among nests with one or multiple fathers because of a limited sample size of single father nests. Regardless, my thesis provides preliminary evidence (number of males per nest) that the density of males off Florida’s beaches may be relatively high, which is expected to be a driver behind the evolution of polyandry and likely plays a large role both in this population and the prevalence of multiple paternity in green turtles as a whole
62

Genetic determinants of raccoon social behavior in a highly urbanized environment

Hauver, Stephanie Anne 24 June 2008 (has links)
No description available.
63

Extra-pair paternity within the female-defense polygyny of the lizard, Anolis carolinensis: Evidence of alternative mating strategies

Passek, Kelly Marie 15 July 2002 (has links)
Mate competition is a prominent component of sexual selection theory. Typically, males attempt to mate with the most females possible and females attempt to mate with the highest quality males possible. In the polygynous female-defense mating system of Anolis carolinensis, males compete directly for females through territorial behavior. Inter-male competition is intense due to an average polygyny ratio of 1 male to 3 females despite a 1:1 adult sex ratio. Through high levels of territorial behavior (e.g., 100 displays/h, 27 m patrol distances/h, 70% of day in defense-related activities), males attempt to exclude other males from resident females who, in turn, both store sperm and ovulate a single-egg clutch at weekly intervals over a 4-month breeding season. Paternity of hatchlings in 16 naturally occurring breeding groups was analyzed to determine the extent to which the territorial resident male was able to prevent other males from fathering offspring of his resident females. Lizards residing in or neighboring a resident male's territory were collected and RAPD-PCR was used to determine the paternity of hatchlings. Of the 48 hatchlings from 26 females, resident territorial males fathered 52% of hatchlings; 15% were fathered by a male whose territory bordered that of the resident male and 21% were fathered by a smaller male living covertly within the resident male's territory. Paternity for the remaining 12% of hatchlings belonged to an unsampled male. Given that females mated with multiple males, laboratory-based controlled matings were conducted where females were sequentially paired with two males and RAPD-PCR was used to analyze which of the two males fathered the subsequent hatchlings to determine the mechanism of sperm precedence. Regardless of mating order, only one male of the pair fertilized the eggs. Male A. carolinensis have reproductive strategies present in addition to defending resident females and female A. carolinensis have options in addition to simply mating with the resident male. While sperm precedence is present in this species, it is not based on mating order, but may involve both the number of sperm deposited in the female's tract as well as the quality of those sperm. / Ph. D.
64

Epaulet Color and Sexual Selection in the Red-Winged Blackbird: A Field Experiment

Yasukawa, Ken, Enstrom, David A., Parker, Patricia G., Jones, Thomas C. 01 November 2009 (has links)
The epaulets of male Red-winged Blackbirds (Agelaius phoeniceus) function in both intersexual and intrasexual contexts, but there is little evidence that they covary with reproductive success in this well-studied species. We used path analysis of male/territory traits, mating success, and reproductive success of unmanipulated males to estimate current directional selection. Territory size had a positive effect on number of within-pair mates. Number of extra-pair mates had a positive effect on number of extra-pair fledglings, and number of within-pair and extra-pair fledglings had positive effects on total number of fledglings. We also reddened epaulets of free-living territorial males to determine whether manipulated and control males differ in territorial behavior, mating success, or reproductive success. Compared with control males, males with reddened epaulets incurred elevated rates of trespassing and territorial challenges, lost their territories more often, and were unable to produce extra-pair offspring. Despite these differences, however, the realized reproductive success of experimental and control males did not differ significantly, perhaps because males with reddened epaulets devoted more time to anti-predator vigilance and were more aggressive toward a simulated predator than were control males. An apparent lack of current sexual selection on epaulet color may be a form of counter-balancing sexual selection in which male aggression against redder epaulets opposes female preference for redder epaulets, or it might be the result of males compensating for lost extra-pair fertilizations by increasing their parental care.
65

ANÁLISES COMPARATIVAS DAS PROBABILIDADES DE PATERNIDADE OBTIDAS A PARTIR DE DIFERENTES BANCOS DE DADOS POPULACIONAIS DO BRASIL.

Almeida, Jonas Garcia de 26 March 2015 (has links)
Submitted by admin tede (tede@pucgoias.edu.br) on 2016-08-18T13:03:27Z No. of bitstreams: 1 Jonas Garcia de Almeida.pdf: 3226956 bytes, checksum: 9d13dc0a531d222433b4267892b08ac2 (MD5) / Made available in DSpace on 2016-08-18T13:03:27Z (GMT). No. of bitstreams: 1 Jonas Garcia de Almeida.pdf: 3226956 bytes, checksum: 9d13dc0a531d222433b4267892b08ac2 (MD5) Previous issue date: 2015-03-26 / For human identification purposes in Forence area, the United States created the database (DB) of DNA Index System Combined (CODIS), containing 13 loci: CSF1PO, FGA, TH01, TPOX, VWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51 and D21S11. Then the DBs of the markers of the Y-STR X-STRs haplotypes were created. Comparison of the obtained data was conducted from allele frequencies (AF), paternity index (PI) by marker and paternity probabilities (PPs) obtained from nine BD population, one of those national (BR), using 241 cases containing the PP 99.99 using 13 loci STRs (CODIS) and 2 more STRs markers of Penta D- and E, granted by the BDs of Núcleo de Pesquisas Replicon, of the Pontifícia Universidade Católica de Goiás (PUC - GO) and LaGene, Laboratório Central de Saúde Pública (SES - GO). 241 cases were analyzed in Trio (alleged father, son and progenitor) and Duo (alleged father and son) situations, using 13 STRs markers (CODIS) by Bayes theorem and the Likelihood Ratio (LR). The results were submitted to the Kruskal-Wallis, chi-square, Spearman correlation and Fishers exact tests and SPSS software (2010). Static analysis of RV cases containing the Trio resulted in 1,148 results PPs 99.99% and 21 results PPs <99.99%, and in a position to Duo 1686 results with PPs 99.99% and 483 results PPs <99.99%. The analysis of the IP average of each marker showed the D21S11 of STRs markers and FGA with the highest power of inclusion and TH01 and D3S1358 with the lowest power of inclusion. The PPs did not show significantly different, containing mostly positive correlation, of moderate to strong, between 8 BDs compared to the BR population databases. This study demonstrated the statistics interference that each allele frequencies DB can have in PP calculations using only 13 loci of genetic, thus making it more significant in cases Duo situation. According to the information available in databases of gene frequencies of the different geographical regions of Brazil, it became possible to conclude that the allele frequencies obtained and the IPs per marker and PPs obtained, suggest strong similarities to those found in the national database. / Para fins de identificação humana na área forense os Estados Unidos criou o Banco de Dados (BD) do Sistema de Índice de DNA Combinado (CODIS), contendo 13 loci: CSF1PO, FGA, TH01, TPOX, VWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51 e D21S11. Foi realizado no presente estudo, a comparação dos dados obtidos das frequências alélicas (FA), índices de paternidade (IP) por marcador e probabilidades de paternidade (PPs) obtidas a partir de 9 BD populacionais, sendo 1 nacional (BR), utilizando 241 casos contendo a PP 99,99 com o uso de 13 loci STRs (CODIS) e mais 2 marcadores STRs do Penta-D e E, cedidos pelos BDs do Núcleo de Pesquisa Replicon, da Pontifícia Universidade Católica de Goiás (PUC-GO) e do LaGene, Laboratório Central de Saúde Pública (SES-GO). Os 241 casos foram analisados nas situações de Trio (suposto pai, filho e genitora) e Duo (suposto pai e filho) usando 13 marcadores STRs (CODIS) através do teorema de Bayes e pela Razão de Verossimilhança (RV). Os resultados foram submetidos aos testes de Kruskal-Wallis, Qui-quadrado, Correlação de Spearman e Exato de Fisher usando o software SPSS (2010). As análises estáticas da RV dos casos contendo o Trio resultaram em 1.148 resultados com PPs 99,99% e 21 resultados com PPs < 99,99%, e em situação de Duo 1.686 resultados com PPs 99,99% e 483 resultados com PPs < 99,99%. As análises das médias dos IPs de cada marcador demonstraram os marcadores STRs do D21S11 e FGA com os maiores poder de inclusão e TH01 juntamente com o D3S1358 os menores poderes de inclusão. As PPs não apresentaram diferenças estatísticas significativas contendo em sua maioria correlações positivas de moderadas a fortes entre os 8 BDs comparados ao BDs populacional do BR. Este estudo demonstrou as interferências estatísticas que cada BDs de frequências alélicas pode exercer nos cálculos de PP quando se utiliza apenas 13 loci para confirmação de vínculo genético, tornando-se assim mais significativas nos casos em situação de Duo. De acordo as informações disponíveis nos BDs de frequências alélicas das diferentes regiões geográficas do Brasil, tornou-se possível concluir, que as frequências alélicas obtidas, bem como os IPs por marcador e as PPs obtidas, sugerem fortes similaridades às encontradas no banco de dados nacional.
66

Um novo modelo para cálculo de probabilidade de paternidade - concepção e implementação / A Novel Model for Paternity Probability Calculation - Design and Implementation

Nakano, Fábio 09 November 2006 (has links)
Nesta tese são apresentados um novo modelo estatístico para cálculo de probabilidade de paternidade e sua implementação em software. O modelo proposto utiliza o genótipo como informação básica, em contraste com outros modelos que usam alelos. Por esta diferença, o modelo proposto resulta mais abrangente, mas que, sob certas restrições, reproduz os resultados dos modelos que usam alelos. Este modelo foi implementado em um software que recebe descrições da genealogia e dos marcadores em uma linguagem dedicada a isso e constrói uma rede bayesiana para cada marcador. O usuário pode definir livremente a genealogia e os marcadores. O cálculo da probabilidade de paternidade é feito, sobre as redes construídas, por um software para inferência em redes bayesianas e a probabilidade de paternidade combinada considerando todos os marcadores é calculada, resultando em um \"índice de paternidade. / This thesis presents a novel statistical model for calculation of the probability of paternity and its implementation as a software. The proposed model uses genotype as basic information. Other models use alleles as basic information. As a result the proposed model is broader, in the sense that, under certain constraints the results from the other models are reproduced. The software implementation receives pedigree and markers data, in a specifically designed language, as input and builds one bayesian network for each marker. The user can freely define any pedigree and any marker. Paternity probabilities for each locus are calculated, from the built networks, by a software for inference on Bayesian Networks and these probabilities are combined into a single \"paternity index\".
67

The Genetic and Social Mating System of a White-Backed Population of the Australian Magpie (Gymnorhina tibicen tyrannica)

Durrant, Kate, n/a January 2004 (has links)
The Australian magpie (Gymnorhina tibicen) is a large, sedentary, omnivorous passerine. In some populations, individuals live in groups, and some of these groups breed cooperatively. The white-backed magpie (G. t. tyrannica) from the south-eastern corner of the continent, has had relatively little study, and few details are known of its mating system, social structure, and method of parental care. I conducted an observational study on a population of white-backed magpies, recording details of their demography, dispersal, breeding system, and parental care. In conjunction, I conducted a genetic analysis of the population, to determine if the genetic mating system matched the observed social system, to detect instances of extra-group mating, and to sex juvenile birds. Extra-pair paternity (EPP) is a common feature of the mating systems of many birds. The rate of EPP may vary between species, races and populations. I made a comparison of extra-group paternity (EGP) rates between two races of the Australian magpie, to determine if similar mating systems were being employed. The two populations had similar social structure, but differed in group size and dispersal. I predicted that dispersal differences would have a profound effect on the rate of EGP between the populations, as the population with the lower rate of dispersal and higher chance of breeding with a close relative would engage in EGPs more frequently. Eight microsatellite loci were used to determine parentage in the white-backed Australian magpie. The rate of EGP was found to be 44%. Dispersal rates were estimated from observational data. Over half of the juvenile magpie cohort from the previous breeding season leave the territorial group. These results contrast sharply with the results found by other researchers in a population of western Australian magpies (G t. dorsalis). In this population, 82% EGP is recorded and dispersal of juveniles is close to nil. The results indicate that dispersal rate is a potentially important predictor of rates of extra-group fertilisations between populations of this species, and suggest that females maximise their reproductive output by avoiding breeding with close kin. The reproductive success of a male bird is often correlated with measurable traits that predict his intrinsic quality. Females are thought to select mates based on their quality to gain their 'good genes'. Male Australian magpies of the white-backed race were trapped in two breeding seasons. Measurements were taken of morphometric and other characteristics in order to discover whether particular traits of males were associated with: a) number of fledglings produced in the territory per season; b) percentage of offspring sired in the territory; and c) whether females select males for their 'good genes'. The only variable that was correlated with number of territorial offspring was feather lice load. Males with high numbers of lice were less likely to produce territorial fledglings in one season and across both seasons. Males of inferior quality may be subject to increased conspecific territorial intrusions, leading to more time spent on defence, more failed breeding attempts, less time allocated to grooming and thus high parasite loads. Males that produced many territorial fledglings were more likely to gain genetic paternity of at least some of them, although again this was significant for only one season. Also, across both seasons, a high number of females in the group was correlated with increased paternity within the group. The general lack of correlation between the variables and level of genetic paternity may be due to females engaging in extra-group mating primarily to avoid breeding with a close relative rather than to choose a quality male. In this scenario, males would not have to be 'high quality', but merely genetically different to the female's social mate. Extra-group paternity (EGP) can affect paternal effort. It may also influence the helping effort of auxiliary birds in cooperatively breeding species. If helping is driven by kin selection, helpers should decline to provision unrelated young. Relatedness becomes difficult to assess however, when females mate outside the group. Alternative rewards may then become important in helper decisions. In my study population of Australian magpies, 38% of fledglings were sired by males outside the territorial group. In a second population (G. t. dorsalis), 82% of fledglings were sired by extra-group males. I observed within-group male and helper feeding effort over three breeding seasons in the first population and obtained data recorded over a single season in the second population. In both populations, males provisioned young regardless of relatedness, as did helpers. Males provisioned less than the nesting female on average. Paternal effort did not reduce with an increase in the rate of EGP between populations. In the population with intermediate levels of EGP, the white-backed magpies, I observed helpers in about half of the sampled territories that produced fledglings. Helpers did not increase the production of young. In the population with high levels of EGP, western magpies, I detected helping behaviour in proportionally more territories. It appears that Australian magpie helpers provide help in order to pay 'rent' and remain on the natal territory. I discuss these results in light of the differences between the two races of magpie and the major theories regarding male parenting decisions and helper activity. Finally, I examine the relatively high rates of EGP's in the Australian magpie from a phylogenetic perspective. Although inbreeding avoidance is strongly supported by this study as the major reason EGP is so common in magpie populations, there may be an element of phylogenetic inertia that maintains the frequency of this behavioural trait. I comment upon the use of single-population estimates of species EGP rates in comparative analyses, given the intraspecific variation discovered between Australian magpie populations. Future directions for the study of mate choice in the Australian magpie are outlined with a proposal to study variation at the major histocompatibility complex between mated pairs.
68

Das deutsche und italienische internationale Kindschaftsrecht im Rechtsvergleich : favor filii oder favor filiationis? /

Heyde, Irene von der. January 2004 (has links) (PDF)
Univ., Diss.--Hamburg, 2003. / Literaturverz. S. 215 - 226.
69

Um novo modelo para cálculo de probabilidade de paternidade - concepção e implementação / A Novel Model for Paternity Probability Calculation - Design and Implementation

Fábio Nakano 09 November 2006 (has links)
Nesta tese são apresentados um novo modelo estatístico para cálculo de probabilidade de paternidade e sua implementação em software. O modelo proposto utiliza o genótipo como informação básica, em contraste com outros modelos que usam alelos. Por esta diferença, o modelo proposto resulta mais abrangente, mas que, sob certas restrições, reproduz os resultados dos modelos que usam alelos. Este modelo foi implementado em um software que recebe descrições da genealogia e dos marcadores em uma linguagem dedicada a isso e constrói uma rede bayesiana para cada marcador. O usuário pode definir livremente a genealogia e os marcadores. O cálculo da probabilidade de paternidade é feito, sobre as redes construídas, por um software para inferência em redes bayesianas e a probabilidade de paternidade combinada considerando todos os marcadores é calculada, resultando em um \"índice de paternidade. / This thesis presents a novel statistical model for calculation of the probability of paternity and its implementation as a software. The proposed model uses genotype as basic information. Other models use alleles as basic information. As a result the proposed model is broader, in the sense that, under certain constraints the results from the other models are reproduced. The software implementation receives pedigree and markers data, in a specifically designed language, as input and builds one bayesian network for each marker. The user can freely define any pedigree and any marker. Paternity probabilities for each locus are calculated, from the built networks, by a software for inference on Bayesian Networks and these probabilities are combined into a single \"paternity index\".
70

Alternativní reprodukční strategie a pohlavní výběr u vlaštovky obecné Hirundo rustica / Alternative reproductive strategies and sexual selection in barn swallow Hirundo rustica

Michálková, Romana January 2021 (has links)
Molecular techniques have revealed that avian mating system is more diverse and complex than previously thought. Both males and females can use alternative reproductive tactics to increase their fitness. Here, we have determined the prevalence of conspecific brood parasitism (CBP, 22% of nests), quasi-parasitism (QP, 6.5% of nests) and extra-pair paternity (EPP, 51.2% of nests) in European subspecies of barn swallow (Hirundo rustica rustica). In contrast to EPP and CBP, QP is rare and has been described in only a few bird species. Our data indicate nonrandom QP patterns, suggesting that this tactic can be considered a third alternative reproductive strategy, alongside CBP and EPP. Sexual ornaments are usually assumed to evolve as condition-dependent signals of individual quality. In this context, a positive correlation between the expression of ornamental traits and survival, is expected. Evolutionary theory predicts that females seek extra-pair fertilizations from high-quality (more ornamented) males and EPP has consequently been proposed as a principal protagonist in the evolution of male secondary sexual traits, however empirical evidence in support of the assertion is relatively scarce. Despite decades of research into the role of EPP in sexual selection, the potential fitness advantages for...

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