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Evaluation of an average numerator relationship matrix model and a Bayesian hierarchical model for growth traits in Nellore cattle with uncertain paternity

Shiotsuki, L.; Cardoso, F. F.; Silva, J. A. Il. V.; Rosa, G. J. M.; Albuquerque, Lucia Galvão de
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 89-95
ENG
Relevância na Pesquisa
36.69%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Processo FAPESP: 06/58896-6; The objective of this work was to compare a model based on the use of an average numerator relationship matrix (ANRM) and a hierarchical animal model (HIER) to indicate the most appropriate statistical procedure to better estimate the genetic value of Nellore animals that have unknown paternity. The data set contained records of 62,212 Nellore animals. The pedigree file contained a total of 75,088 animals. Two approaches were adopted for the treatment of uncertain paternity. In the model based on the use of the ANRM probabilities were attributed to each of the possible parents of the animals with uncertain paternity. The other method adopted in the present study, i.e., the HIER, considers uncertainty in the assignment of paternity of animals participating in the multiple-sire (MS) system. Within this context, a priori probabilities are assigned to each possible sire of animals with uncertain paternity, which are altered according to information present in the data for the generation of posterior probabilities. Univariate analyses were carried out under Bayesian approach via Markov Chain Monte Carlo (MCMC) methods...

Diversidade genética, ancestralidade individual e miscigenação nas raças bovinas no Brasil com base em Microssatélites e Haplótipos de DNA Mitocandrial : subsídios para a conservação

Egito, Andréa Alves do
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Tese
POR
Relevância na Pesquisa
16.11%
Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Biologia Celular, 2007.; O Brasil possui o maior rebanho bovino comercial do mundo e as raças criadas no País podem ser classificadas, de acordo com sua origem, em comerciais e exóticas. As raças exóticas, importadas nos últimos 100 anos, taurinas e zebuínas, compõem atualmente o conjunto populacional de maior influência e manejo intensivo. As raças localmente adaptadas, originadas do gado introduzido pelos colonizadores europeus derivam-se da seleção e dos eventos naturais ocorridos na formação de uma raça. Embora exista um conhecimento histórico a respeito das raças crioulas brasileiras muito pouco se sabe de sua composição genética. Como o progresso da pecuária está relacionado com a variabilidade genética, sua perda poderá restringir as opções, não previstas, para os trabalhos de melhoramento animal. Estudos sobre a diversidade e variabilidade genética da espécie bovina poderão auxiliar decisões a respeito de quais populações devem ser conservadas, quando os recursos são escassos, evitando a duplicação de esforços na manutenção de amostras. Podem ainda assegurar a manutenção da variabilidade genética...

Paternity assessment in free ranging wild boar (Sus scrofa) - Are littermates full-sibs?

Delgado, R.; Fernández-Llario, P.; Azevedo, M.; Beja-Pereira, A.; Santos, P.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica Formato: 179251 bytes; application/pdf
ENG
Relevância na Pesquisa
26.69%
Multiple paternity within litters occurs in various groups of mammals exhibiting different mating systems. Using seven genetic markers (i.e., microsatellites) we investigated the paternity of littermates in free ranging wild boar (Sus scrofa) in a Mediterranean habitat. Using the software CERVUS 2.0 we estimated the probability of detecting multiple paternity across all loci (D), the probability of paternity (W) and a statistic ∆ that allows the assignment of paternity to the most likely male with strict and relaxed levels of confidence. Multiple paternity was inferred for one of the nine analysed litters at the 80% confidence level. This suggests that a single male may control the access to receptive adult females and it shows that multiple paternity is not very common in the studied free ranging wild boar population. Despite the possible occurrence of sperm competition and/or female cryptic choice, mate guarding seems to play a significant role in sexual selection. To better understand the wild boar’s mating strategies further studies analysing the reproductive success of both sexes and under different environmental conditions should be conducted.

Paternity and relatedness in wild chimpanzee communities

Vigilant, Linda; Hofreiter, Michael; Siedel, Heike; Boesch, Christophe
Fonte: The National Academy of Sciences Publicador: The National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
36.63%
The genetic structure of three contiguous wild chimpanzee communities in West Africa was examined to determine the extent to which the community, the mixed-sex social unit of chimpanzees, represents a closed reproductive unit. An analysis of paternity for 41 offspring resulted in 34 cases of paternity assignment to an adult male belonging to the same community. Among the 14 offspring for which all potential within-community fathers have been tested, one likely case of extra-group paternity (EGP) has been identified, suggesting an incidence of EGP of 7%. This more extensive analysis contradicts a previous genetic study of the Taï chimpanzees that inferred 50% extra-group fathers. We suggest, based on direct comparison of results for 33 individuals at 1 microsatellite locus and direct comparison of paternity assignments for 11 offspring, that the error rate in the previous study was too high to produce accurate genotypes and assignments of paternity and hence caused the false inference of a high rate of EGP. Thus, the community is the primary but not exclusive unit for reproduction in wild chimpanzees, and females do not typically reproduce with outside males. Despite the inferred low level of gene flow from extra-community males, relatedness levels among the community males are not significantly higher than among community females...

Genetic Analysis of Male Reproductive Contributions in Chamaelirium Luteum (L.) Gray (Liliaceae)

Smouse, P. E.; Meagher, T. R.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/1994 EN
Relevância na Pesquisa
16.78%
Genealogical analysis is a powerful tool for analysis of reproductive performance in both natural and captive populations, but assignment of paternity has always been a stumbling block for this sort of work. Statistical methods for determining paternity have undergone several phases of development, ranging from straightforward genetic exclusion to assignment of paternity based on genetic likelihood criteria. In the present study, we present a genetic likelihood-based iterative procedure for fractional allocation of paternity within a progeny pool and apply this method to a population of Chamaelirium luteum, a dioecious member of the Liliaceae. Results from this analysis clearly demonstrate that different males make unequal contributions to the overall progeny pool, with many males contributing essentially nothing to the next generation. Furthermore, the distribution of paternal success among males shows a highly significant departure from (Poisson) randomness. The results from the present analysis were compared with earlier results obtained from the same data set, using likelihood-based categorical paternity assignments. The general biological pattern revealed by the two analyses is the same, but the estimates of reproductive success are only modestly (though significantly) correlated. The iterative procedure makes more complete use of the data and generates a more sharply resolved distribution of male reproductive success.

Statistical approaches to paternity analysis in natural populations and applications to the North Atlantic humpback whale.

Nielsen, R; Mattila, D K; Clapham, P J; Palsbøll, P J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/2001 EN
Relevância na Pesquisa
36.6%
We present a new method for paternity analysis in natural populations that is based on genotypic data that can take the sampling fraction of putative parents into account. The method allows paternity assignment to be performed in a decision theoretic framework. Simulations are performed to evaluate the utility and robustness of the method and to assess how many loci are necessary for reliable paternity inference. In addition we present a method for testing hypotheses regarding relative reproductive success of different ecologically or behaviorally defined groups as well as a new method for estimating the current population size of males from genotypic data. This method is an extension of the fractional paternity method to the case where only a proportion of all putative fathers have been sampled. It can also be applied to provide abundance estimates of the number of breeding males from genetic data. Throughout, the methods were applied to genotypic data collected from North Atlantic humpback whales (Megaptera novaeangliae) to test if the males that appear dominant during the mating season have a higher reproductive success than the subdominant males.

Weak Polygyny in California Sea Lions and the Potential for Alternative Mating Tactics

Flatz, Ramona; González-Suárez, Manuela; Young, Julie K.; Hernández-Camacho, Claudia J.; Immel, Aaron J.; Gerber, Leah R.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 14/03/2012 EN
Relevância na Pesquisa
16.35%
Female aggregation and male territoriality are considered to be hallmarks of polygynous mating systems. The development of genetic parentage assignment has called into question the accuracy of behavioral traits in predicting true mating systems. In this study we use 14 microsatellite markers to explore the mating system of one of the most behaviorally polygynous species, the California sea lion (Zalophus californianus). We sampled a total of 158 female-pup pairs and 99 territorial males across two breeding rookeries (San Jorge and Los Islotes) in the Gulf of California, Mexico. Fathers could be identified for 30% of pups sampled at San Jorge across three breeding seasons and 15% of sampled pups at Los Islotes across two breeding seasons. Analysis of paternal relatedness between the pups for which no fathers were identified (sampled over four breeding seasons at San Jorge and two at Los Islotes) revealed that few pups were likely to share a father. Thirty-one percent of the sampled males on San Jorge and 15% of the sampled males on Los Islotes were assigned at least one paternity. With one exception, no male was identified as the father of more than two pups. Furthermore, at Los Islotes rookery there were significantly fewer pups assigned paternity than expected given the pool of sampled males (p<0.0001). Overall...

How Attractive Is the Girl Next Door? An Assessment of Spatial Mate Acquisition and Paternity in the Solitary Cape Dune Mole-Rat, Bathyergus suillus

Bray, Timothy C.; Bloomer, Paulette; O’Riain, M. Justin; Bennett, Nigel C.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 29/06/2012 EN
Relevância na Pesquisa
26.55%
Behavioural observations of reproduction and mate choice in wild fossorial rodents are extremely limited and consequently indirect methods are typically used to infer mating strategies. We use a combination of morphological, reproductive, spatial, and genetic data to investigate the reproductive strategy of a solitary endemic species, the Cape dune mole-rat Bathyergus suillus. These data provide the first account on the population dynamics of this species. Marked sexual dimorphism was apparent with males being both significantly larger and heavier than females. Of all females sampled 36% had previously reproduced and 12% were pregnant at the time of capture. Post-partum sex ratio was found to be significantly skewed in favour of females. The paternity of fifteen litters (n = 37) was calculated, with sires assigned to progeny using both categorical and full probability methods, and including a distance function. The maximum distance between progeny and a putative sire was determined as 2149 m with males moving between sub-populations. We suggest that above-ground movement should not be ignored in the consideration of mate acquisition behaviour of subterranean mammals. Estimated levels of multiple paternity were shown to be potentially as high as 26%...

Body Size Correlates with Fertilization Success but not Gonad Size in Grass Goby Territorial Males

Pujolar, Jose Martin; Locatello, Lisa; Zane, Lorenzo; Mazzoldi, Carlotta
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 04/10/2012 EN
Relevância na Pesquisa
16.11%
In fish species with alternative male mating tactics, sperm competition typically occurs when small males that are unsuccessful in direct contests steal fertilization opportunities from large dominant males. In the grass goby Zosterisessor ophiocephalus, large territorial males defend and court females from nest sites, while small sneaker males obtain matings by sneaking into nests. Parentage assignment of 688 eggs from 8 different nests sampled in the 2003–2004 breeding season revealed a high level of sperm competition. Fertilization success of territorial males was very high but in all nests sneakers also contributed to the progeny. In territorial males, fertilization success correlated positively with male body size. Gonadal investment was explored in a sample of 126 grass gobies collected during the period 1995–1996 in the same area (61 territorial males and 65 sneakers). Correlation between body weight and testis weight was positive and significant for sneaker males, while correlation was virtually equal to zero in territorial males. That body size in territorial males is correlated with fertilization success but not gonad size suggests that males allocate much more energy into growth and relatively little into sperm production once the needed size to become territorial is attained. The increased paternity of larger territorial males might be due to a more effective defense of the nest in comparison with smaller territorial males.

Genetic Evidence Confirms Polygamous Mating System in a Crustacean Parasite with Multiple Hosts

Jossart, Quentin; Wattier, Rémi A.; Kastally, Chedly; Aron, Serge; David, Bruno; De Ridder, Chantal; Rigaud, Thierry
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 07/03/2014 EN
Relevância na Pesquisa
16.11%
Mating systems are diverse in animals, notably in crustaceans, but can be inferred from a limited set of parameters. Baeza and Thiel (2007) proposed a model predicting mating systems of symbiotic crustaceans with three host characteristics and the risk of predation. These authors proposed five mating systems, ranging from monogamy to polygynandry (where multiple mating occurs for both genders). Using microsatellite loci, we tested the putatively mating system of the ectoparasite crab Dissodactylus primitivus. We determined the mating frequencies of males and females, parentage assignment (COLONY & GERUD software) as well as the contents of female spermathecae. Our results are globally consistent with the model of Baeza and Thiel and showed, together with previous aquarium experiments, that this ectoparasite evolved a polygamous mating system where males and females move between hosts for mate search. Parentage analyses revealed that polyandry is frequent and concerns more than 60% of clutches, with clutches being fertilized by up to 6 different fathers. Polygyny is supported by the detection of eight males having sired two different broods. We also detected a significant paternity skew in 92% of the multipaternal broods. Moreover, this skew is probably higher than the estimation from the brood because additional alleles were detected in most of spermathecae. This high skew could be explained by several factors as sperm competition or cryptic female choice. Our genetic data...

A High Throughput Single Nucleotide Polymorphism Multiplex Assay for Parentage Assignment in New Zealand Sheep

Clarke, Shannon M.; Henry, Hannah M.; Dodds, Ken G.; Jowett, Timothy W. D.; Manley, Tim R.; Anderson, Rayna M.; McEwan, John C.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 16/04/2014 EN
Relevância na Pesquisa
26.82%
Accurate pedigree information is critical to animal breeding systems to ensure the highest rate of genetic gain and management of inbreeding. The abundance of available genomic data, together with development of high throughput genotyping platforms, means that single nucleotide polymorphisms (SNPs) are now the DNA marker of choice for genomic selection studies. Furthermore the superior qualities of SNPs compared to microsatellite markers allows for standardization between laboratories; a property that is crucial for developing an international set of markers for traceability studies. The objective of this study was to develop a high throughput SNP assay for use in the New Zealand sheep industry that gives accurate pedigree assignment and will allow a reduction in breeder input over lambing. This required two phases of development- firstly, a method of extracting quality DNA from ear-punch tissue performed in a high throughput cost efficient manner and secondly a SNP assay that has the ability to assign paternity to progeny resulting from mob mating. A likelihood based approach to infer paternity was used where sires with the highest LOD score (log of the ratio of the likelihood given parentage to likelihood given non-parentage) are assigned. An 84 “parentage SNP panel” was developed that assigned...

Estimating quantitative genetic parameters in wild populations: a comparison of pedigree and genomic approaches

Bérénos, Camillo; Ellis, Philip A; Pilkington, Jill G; Pemberton, Josephine M
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
16.11%
The estimation of quantitative genetic parameters in wild populations is generally limited by the accuracy and completeness of the available pedigree information. Using relatedness at genomewide markers can potentially remove this limitation and lead to less biased and more precise estimates. We estimated heritability, maternal genetic effects and genetic correlations for body size traits in an unmanaged long-term study population of Soay sheep on St Kilda using three increasingly complete and accurate estimates of relatedness: (i) Pedigree 1, using observation-derived maternal links and microsatellite-derived paternal links; (ii) Pedigree 2, using SNP-derived assignment of both maternity and paternity; and (iii) whole-genome relatedness at 37 037 autosomal SNPs. In initial analyses, heritability estimates were strikingly similar for all three methods, while standard errors were systematically lower in analyses based on Pedigree 2 and genomic relatedness. Genetic correlations were generally strong, differed little between the three estimates of relatedness and the standard errors declined only very slightly with improved relatedness information. When partitioning maternal effects into separate genetic and environmental components, maternal genetic effects found in juvenile traits increased substantially across the three relatedness estimates. Heritability declined compared to parallel models where only a maternal environment effect was fitted...

Microsatellite parentage analysis of a semi-wild population of southern white rhinoceros (Ceratotherium simum simum): pedigree construction and variance in male mating success

Auld, Hailie
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
16.11%
The southern white rhinoceros (Ceratotherium simum simum) is considered a conservation success story after having been rehabilitated from only 20 individuals to over 20,000 today. Despite this success, this subspecies is characterized by low genetic variability. Recovering genetic diversity is key but difficult in small populations and for a species where little is known about population dynamics. This study used microsatellite parentage analysis to determine the mating system dynamic of a free-ranging, semi-wild population of southern white rhinoceros in South Africa with two cohorts of breeding males. Using two parentage methods, as well as known mother-calf relationships to increase the robustness of paternity assignments, 66% of the offspring were matched to a putative father. Analysis revealed that mating was skewed towards one male in the first cohort siring 37.5% of the offspring; this male was more related to the breeding females. This suggests a non-genetic characteristic influencing mate choice. Difficulties in assignment were attributed to high relatedness (r=0.245) among the second set of males and low genetic variation. This study argues that understanding the mating system is an important and immediately realizable goal for successful management of this species.

High levels of genetic contamination in remnant populations of Acacia saligna from a genetically divergent planted stand

Millar, M.; Byrne, M.; Nuberg, I.; Sedgley, M.
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
36.73%
It is essential to understand the patterns of pollen dispersal in remnant vegetation occupying highly disturbed landscapes in order to provide sustainable management options and to inform restoration programs. Direct and indirect methods of paternity analysis were used to detect genetic contamination via inter-subspecific pollen dispersal from a planted stand of nonlocal Acacia saligna ssp. saligna (ms) into remnant roadside patches of local A. saligna ssp. lindleyi (ms). Genetic contamination was detected in 25.5% (indirect paternity assignment) to 32% (direct paternity assignment) of ssp. lindleyi progeny and occurred over a distance of 1.6 km. The results support studies that suggest genetic continuity is maintained by high levels of pollen dispersal in temperate entomophilous species. The results also indicate that patchily distributed remnant populations may be exposed to substantial amounts of genetic contamination from large-scale restoration with native taxa in the highly fragmented agricultural landscape of southern Western Australia. Management practices to reduce the risk of genetic contamination are considered.; Melissa A. Millar, Margaret Byrne, Ian K. Nuberg and Margaret Sedgley

Comparison of Women's Policies in Six International Navies

Eitelberg, Mark J.; Aten, Kathryn J.; Smith, Michael K.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Relatório
Relevância na Pesquisa
16.11%
Approved for public release; distribution in unlimited.; Approved for public release; distribution in unlimited.; The present study compares policies, programs, and practices relating to women in six international navies. Navies from the following nations are included: the United States, Australia, Brazil, Canada, Sweden, and the United Kingdom. Information is drawn from answers by representatives of the six international navies to a detailed questionnaire fielded from May through September 2014. The questionnaire covers eight topic areas: General Information; Maternity/Paternity Issues; Deployments; Assignment; Marriage; Career Path & Development; Navy Policy Development; and Other Information. Additionally, project researchers organized and advised three Master’s thesis projects at the Naval Postgraduate School; these are reported separately. Questionnaire responses are catalogued and compared in 23 tables. Results reveal a similar emphasis on family, the flexible workplace, and various initiatives to encourage the recruiting and retention of highly-qualified women. Selected “best practices” are also identified. A preliminary factors model is introduced for future use in identifying and comparing international policies and practices. Recommendations for further research include expanding the study to include more international navies...

The evolutionary biology of pollination: studies in a genus of australian sexually deceptive orchids

Whitehead, Michael Robert
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD); Doctor of Philosophy (PhD)
EN_AU
Relevância na Pesquisa
36.55%
There are few other structures in nature from which evolution has generated such wide diversity as the flower or inflorescence, and this diversity is commonly attributed to the influence of their animal visitors. By outsourcing their mate choice to pollinators, plants have left themselves - and especially their flowers - subject to the selective forces imposed by the behaviour, cognition and perception of the pollinators that serve them. The orchids provide some of the most remarkable and extreme examples of adaptations to specific animal pollinators. Perhaps one of the most peculiar of these strategies is sexual deception, whereby male insects are lured to the flower by mimicry of the female sex pheromone. This seemingly unlikely strategy has evolved multiple times independently on different continents in different parts of the orchid phylogeny which raises the question of what adaptive advantages might underlie such a strategy. This multidisciplinary thesis studies gene flow and pollinator behaviour in two sympatric sexually deceptive orchids in the genus Chiloglottis. The two species attract their specific wasp pollinators through emission of distinct species - specific semiochemicals. Since floral volatiles play a pre-eminent role in pollinator attraction...

The dilemma of female mate selection in the brown bear, a species with sexually selected infanticide

Bellemain, Eva; Zedrosser, Andreas; Manel, Stéphanie; Waits, Lisette P; Taberlet, Pierre; Swenson, Jon E
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.11%
Because of differential investment in gametes between sexes, females tend to be the more selective sex. Based on this concept, we investigate mate selection in a large carnivore: the brown bear (Ursus arctos). We hypothesize that, in this species with sexually selected infanticide (SSI), females may be faced with a dilemma: either select a high-quality partner based on phenotypic criteria, as suggested by theories of mate choice, or rather mate with future potentially infanticidal males as a counter-strategy to SSI. We evaluated which male characteristics were important in paternity assignment. Among males available in the vicinity of the females, the largest, most heterozygous and less inbred and also the geographically closest males were more often the fathers of the female's next litter. We suggest that female brown bears may select the closest males as a counter-strategy to infanticide and exercise a post-copulatory cryptic choice, based on physical attributes, such as a large body size, reflecting male genetic quality. However, male–male competition either in the form of fighting before copulation or during the post-copulatory phase, in the form of sperm competition, cannot entirely be ruled out.

Extrapair Paternity and Maternity in the Three-Toed Woodpecker, Picoides tridactylus: Insights from Microsatellite-Based Parentage Analysis

Li, Meng-Hua; Välimäki, Kaisa; Piha, Markus; Pakkala, Timo; Merilä, Juha
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 18/11/2009 EN
Relevância na Pesquisa
26.47%
Molecular techniques have revealed that avian mating systems are more diverse and complex than previously thought. We used microsatellite markers to determine genetic parentage, the prevalence of extrapair paternity and quasi-parasitism (i.e. situations where a male's extrapair mate lay in his nest) in a socially monogamous population of three-toed woodpeckers (Picoides tridactylus) in southern Finland. A total of 129 adults and nestlings, representing 5–9 families annually from 2004–2007, were genotyped at up to ten microsatellite loci. The results of genetic assignment tests confirmed that monogamous parentage characterized the majority (84.6%, 22/26) of broods, and that most (93.8%, 75/80) nestlings were the offspring of their social parents. Two of 80 nestlings (2.5%) in two of 26 broods (7.7%) were sired by extrapair males and quasi-parasitism occurred in 3.8% (3/80) of nestlings and 7.7% (2/26) of broods. Hence, the levels of extrapair parentage were low, possibly because both genetic polygyny and polyandry are constrained by the high paternal effort required for parental care. The co-occurrence of low levels of extrapair paternity and quasi-parasitism are discussed in light of ecological and behavioural factors characterizing the species biology.

Aspetti del sistema nuziale del Punteruolo rosso delle palme (Rhynchophorus ferrugineus): un approccio molecolare e bioinformatico.

BELVEDERE, SILVIA
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
IT
Relevância na Pesquisa
26.11%
Il Punteruolo rosso delle palme, Rhynchophorus ferrugineus, Olivier (Curculionoidea, Dryophtoridae), è un coleottero originario del Sud-Est asiatico e della Melanesia invasivo in Medio Oriente ed in quasi tutti i paesi del bacino del Mediterraneo, compresa l'Italia. Il fitofago arreca ingenti danni a numerose specie di Arecaceae, tra cui molte palme di interesse economico. Le attuali azioni di controllo integrato, adottate per contenerne l'espansione, si sono rivelate finora insufficienti anche perché manca una approfondita conoscenza del sistema nuziale dell'insetto, ed il suo grande successo riproduttivo è proprio una delle cause principali del enorme potenziale invasivo di questa specie dannosa. Obiettivo generale del progetto di dottorato è stato dunque lo studio di aspetti del mating system del Punteruolo rosso legati ad eventuali comportamenti poliandrici e fenomeni di selezione sessuale post-copulatoria. Sono stati eseguiti a questo scopo dei test di paternità, per mezzo di analisi genetiche e bioinformatiche, sulla prole di esperimenti di incrocio effettuati in laboratorio, in modo da verificare ipotesi alternative riguardanti il sistema nuziale della specie. Date le scarse informazioni genetiche disponibili su R. ferrugineus...

Complex mating system and dispersal patterns in a social lizard, Egernia whitii

Chapple, David; Keogh, J Scott
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
16.53%
In contrast to the polygynous mating systems typically displayed by most reptilian taxa, long-term genetic monogamy appears to be widespread within a lineage of group-living Australian scincid lizards, the Egernia group. We have recently shown that White's skink, Egernia whitii, lives in small but temporally stable social aggregations. Here, we examine the mating system, spatial organization, and dispersal patterns of E. whitii using behavioural field studies and data from four microsatellite loci. Parentage analysis of E. whitii litters revealed that its mating system is characterized by both polygyny and monogamy. Polygyny was the predominant mating system but within-season social and genetic monogamy was common (36-45% of breeding pairs). The incidence of between-season monogamy in E. whitii was rare compared to that reported for its congeners. Low levels of multiple paternity (12% of litters) and extra-group paternity (16%) were detected. Social groups are generally comprised of closely related individuals, but breeding pairs were not more closely related compared to other potential mates. Spatial autocorrelation analyses revealed significant positive local genetic structure over 50 m, which was consistent for all age-sex classes. There was no clear and consistent evidence for sex-biased dispersal...