204 resultados para Paternity


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A changing climate is expected to have profound effects on many aspects of ectotherm biology. We report on a decade-long study of free-ranging sand lizards (Lacerta agilis), exposed to an increasing mean mating season temperature and with known operational sex ratios. We assessed year-to-year variation in sexual selection on body size and postcopulatory sperm competition and cryptic female choice. Higher temperature was not linked to strength of sexual selection on body mass, but operational sex ratio (more males) did increase the strength of sexual selection on body size. Elevated temperature increased mating rate and number of sires per clutch with positive effects on offspring fitness. In years when the “quality” of a female's partners was more variable (in standard errors of a male sexual ornament), clutches showed less multiple paternity. This agrees with prior laboratory trials in which females exercised stronger cryptic female choice when male quality varied more. An increased number of sires contributing to within-clutch paternity decreased the risk of having malformed offspring. Ultimately, such variation may contribute to highly dynamic and shifting selection mosaics in the wild, with potential implications for the evolutionary ecology of mating systems and population responses to rapidly changing environmental conditions.

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 The health benefits of diets containing rich sources of long-chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA) are well documented and include reductions in the risk of several diseases typical of Western societies. The dietary intake of n-3 LC-PUFA has also been linked to fertility, and there is abundant evidence that a range of ejaculate traits linked to fertility in humans, livestock and other animals depend on an adequate intake of n-3 LC-PUFA from dietary sources. However, relatively few studies have explored how n-3 LC-PUFA influence reproductive fitness, particularly in the context of sexual selection. Here, we show that experimental reduction in the level of n-3 LC-PUFA in the diet of guppies (Poecilia reticulata) depresses a male’s share of paternity when sperm compete for fertilization, confirming that the currently observed trend for reduced n-3 LC-PUFA in western diets has important implications for individual reproductive fitness.

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The existence of animal personality is well-established across a wide range of species, with the majority of evidence for this being obtained from individuals held in captivity. However, there has been little work assessing the influence of commonly-measured personality traits on fitness, which is pertinent when the genetic basis of personality is considered. We measured whether the reproductive behaviour and success of zebra finches in a captive mixed-sex aviary environment was influenced by an aspect of their personality, their exploratory behaviour in a single-sex social aviary. We found that more exploratory males made a greater number of breeding attempts and raised more nestlings than less exploratory males. These results were not confounded by extra-pair paternity, which was not related to personality, or by the individuals that did not initiate any reproductive attempts at all. Our work provides evidence that attributes of personality may influence the degree to which individuals cope with, and thrive in a captive environment and this should be accounted for in both experimental design and the interpretation of results. Furthermore, this suggests that there may be selection on these traits as part of the domestication process.

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For dioecious animals, reproductive success typically involves an exchange between the sexes of signals that provide information about mate location and quality. Typically, the elaborate, secondary sexual ornaments of males signal their quality, while females may signal their location and receptivity. In theory, the receptor structures that receive the latter signals may also become elaborate or enlarged in a way that ultimately functions to enhance mating success through improved mate location. The large, elaborate antennae of many male moths are one such sensory structure, and eye size may also be important in diurnal moths. Investment in these traits may be costly, resulting in trade-offs among different traits associated with mate location. For polyandrous species, such trade-offs may also include traits associated with paternity success, such as larger testes. Conversely, we would not expect this to be the case for monandrous species, where sperm competition is unlikely. We investigated these ideas by evaluating the relationship between investment in sensory structures (antennae, eye), testis, and a putative warning signal (orange hindwing patch) in field-caught males of the monandrous diurnal painted apple moth Teia anartoides (Lepidoptera: Lymantriidae) in southeastern Australia. As predicted for a monandrous species, we found no evidence that male moths with larger sensory structures had reduced investment in testis size. However, contrary to expectation, investment in sensory structures was correlated: males with relatively larger antennae also had relatively larger eyes. Intriguingly, also, the size of male orange hindwing patches was positively correlated with testis size.

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Polyandry is an important component of both sexual selection and kin structuring within cooperatively breeding species. A female may have multiple partners within a single reproductive attempt (simultaneous polyandry) or across multiple broods within and/or across years (sequential polyandry). Both types of polyandry confer a range of costs and benefits to individuals and alter the genetic structure of social groups over time. To date, many molecular studies of cooperative breeders have examined the evolution of cooperative breeding in relation to simultaneous polyandry. However, cooperatively breeding vertebrates are iteroparous, and thus sequential polyandry is also likely, but more rarely considered in this context. We examined sequential polyandry in a cooperatively breeding bird that has a low level of within-brood polyandry. Over a 5-year period (2006–2010), we monitored individual mating relationships using molecular markers in a population of individually marked apostlebirds (Struthidea cinerea). Divorce occurred between reproductive seasons in 17 % (8/48) of pairs and appeared to be female-driven. The level of sequential polyandry was also driven by the disappearance of males after breeding, and over 90 % of females, for whom we had suitable data, bred with multiple males over the period of study. This sequential polyandry significantly altered the relatedness of group members to the offspring in the nest. However, in about half of the cases, the second male was related (first- or second-order relative) to the first male of a sequentially polyandrous female and this alleviated the reduction in relatedness caused by polyandry. Our findings suggest that even in species with high within-brood parentage certainty, helper-offspring relatedness values can quickly erode through sequential polyandry.

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O objetivo desta monografia é a análise do direito de família, mais especificamente do instituto da paternidade socioafeitva e seu reflexo em situações atuais como a adoção à brasileira. A metodologia deste trabalho foi baseada na revisão de pesquisas bibliográficas, doutrinárias, legislativas e jurisprudenciais. A análise discorre, primeiramente, acerca do conceito da paternidade socioafetiva e da maneira como que os vínculos sociais e afetivos têm sido avaliados como predominante em relação ao vínculo de consanguinidade, considerando o melhor interesse do menor. Posteriormente foi abordado o tema adoção, a “adoção à brasileira”, e como a mesma, tipificada como crime no Código Penal Brasileiro, pode ser solucionada pelo instituto da filiação socioafetiva. Por fim foram revisadas as apreciações de como os tribunais brasileiros adéquam o procedimento de adoção na nova realidade familiar brasileira, tendo em vista a falta de previsão legal, o que leva para os juízes a decisão acerca deste tema. Paralelamente são apresentados exemplos das decisões tomadas caracterizando jurisprudências no tema.

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Human population have a significant number of polymorphic loci, whose use and applications range from construction of linkage maps, to study the evolution of populations, through the determination of paternity, forensic medicine and migration. Currently, STRs (Short Tanden Repeats) markers are considered the major markers for human identification, mainly due to its abundance and high variability because of the fact that they are easily amplifiable by PCR (Polymerase Chain Reaction), work with low amounts of DNA and be capable of automation processes involving fluorescence detection. The creation of regional databases containing allele frequencies of population provide subsidies to increase the reliability of the results of determining the genetic link. This paper aims to obtain a database of allele frequencies of 15 polymorphic molecular loci (D8S1179, D21S11, D7S820, CSF1PO, D19S433, vWA, TPOX, D18S51, D3S1358, TH01, D13S317, D16S539, D2S1338, D5S818 e FGA) in a population classifies as born in the State of Rio Grande do Norte, Brazil, totaling 1100 unrelated individuals. To evaluate the frequency, DNA samples were submitted to PCR amplification, followed by capilarry electrophoresis genetic sequencer. The frequencies identified in this study were compared with brazilian population in general and other states in Brazil. Except for the loci D21S11, D19S433 and D2D1338, the genotypes found were in Hardy-Weinberg equilibrium and no significant differences among the frequencies were found in the populations studied. The most informative loci was D2S1338 and D18S51, and the less informative is the locus TPOX

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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We describe the isolation and characterization of ten microsatellite loci from the red-winged tinamou (Rhynchotus rufescens) and also evaluated the cross-amplification of these loci and other ten loci previously developed for the great tinamou (Tinamus major) in other tinamous. Genetic variability was assessed using 24 individuals. Six loci were polymorphic with moderate to high number of alleles per locus (2-12 alleles) and showed expected heterozygosity (HE) ranging from 0.267 to 0.860. All loci conformed to the Hardy-Weinberg expectation and linkage disequilibrium was not significant for any pair of loci. This battery of polymorphic loci showed high paternity exclusion probability (0.986) and low genetic identity probability (4.95 x 10(-5)), proving to be helpful for parentage tests and population analyses in the red-winged tinamou. The cross-amplification was moderate where of the 160 locus/taxon combinations, 46 (28.75%) successfully amplified.

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O objeto deste estudo é a figura concreta de um pai, presente em sua corporalidade e afetividade, que se depara com a demanda subjetiva, advinda da exigência de revisão de seu papel no mundo contemporâneo. Buscamos encontrar a paternidade que acolhe e convive com o processo de transformações em marcha: o pai que transita entre valores novos e arcaicos. O acesso a este conhecimento se deu através do método clínico de pesquisa, com apoio da psicanálise. Sem submeter os participantes ao tratamento psicanalítico, aplica seus conceitos na interpretação de fenômeno que tem dimensão subjetiva e também, social. Adotamos a entrevista como principal instrumento e a análise qualitativa enquanto estratégia, por permitir relevância à fala do entrevistado e dela extrair o dado significativo para nossas indagações.

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Locus of control is a construct that seeks to explain people's perceptions about the source of control of events, if the subject's own - internal - or belonging to some element outside of oneself - external. The location of individual s locus of control will suffer influence of their developmental period. During adolescence, individuals turn to the construction of their identity, and the structuring of sexual identity is a relevant part of this process, since the roles of males and females are the most important from the socio-cultural point of view. One of the roles that adolescents can take is the mother or father. We chose to head the adolescents who are not mothers and fathers, and question them about their concepts of parenthood. It is hypothesized that adolescents with internal locus of control will probably develop concepts of maternity and paternity in which they attach to themselves the responsibility for children. The aim of this study was to relate the locus of control s predominant dimension in adolescence and the way that these young people conceptualize parenthood. This is an exploratory analytical cross-sectional study accomplished with 400 adolescents from the classes of the sixth to ninth grade of high school at public schools in Natal / RN. We used as protocols: structured questionnaire involving sociodemographic questions and questions about the concept of parenthood, and the Multifactorial Scale of Locus of Control. Data were analyzed using descriptive and inferential statistics, with the aid of statistical package SPSS 18.0. The results regarding questions about the concept of maternity and paternity were analyzed using the analysis program often ALCESTE 4.7. The results showed that for boys and girls, maternity and paternity were characterized by the acquisition and assumption of responsibilities of adulthood. This concept is supported by the locus of control s classification of individuals, since most of the subjects of this study was characterized as individuals who tend to take responsibility for their life's events. For young people from lower classes (as the subjects of this research), the project of autonomy and social mobility is realized by the constitution of his own family and the ability to sustain it

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Six microsatellite loci were used to quantify the mating system of two small fragmented populations (Selviria - SEL and Aparecida do Tabuado APT, Mato Grosso do Sul State) and isolated trees in pastures, of the bat-pollinated tropical tree Hymenaea stignocarpa, growing in the Center-west region of Brazil. In SEL population, seeds were collected from 11 mother-trees; in APT, from three trees and, in the case of isolated trees, from six individuals growing at least 500 m apart in pastures. To investigate if there are differences on mating system between trees in populations and isolated trees, trees from populations were pooled as a group and, likewise, the isolated trees were pooled to another group. The outcrossing rate was higher in the populations ((t) over cap (m)=0.873) than in isolated trees ((t) over cap (m)=0.857), but the difference was not significant. Significant and high differences between multi-locus and single-locus outcrossing rate were detected in populations ((t) over cap (m)-(t) over cap (s)=0.301, P<0.05) and isolated trees (<(t)over cap>(m)-(t) over cap (s) = 0.276, P < 0.05), suggesting mating between relatives. Higher paternity correlation was observed in trees from population (<(r)over cap>(p)=0.636) than in isolated trees ((r) over cap (p)=0.377), indicating the occurrence of some correlated matings and that part of offspring are full-sibs. It was not observed increased in self-fertilization rate in isolated trees in pastures. In general terms, the unique observed difference in mating system between populations and isolate trees was the high rate of correlated matings in trees from populations, due probably to the small distance among coespecifics and the pollinator behavior, visiting near trees.