775 resultados para Passerine Migrant


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O trabalho se propoe a retratar a realidade da criança migrante na região de destino, mais especificamente no contexto escolar. Tomando por base observações realizadas numa escola do Municipio de Nova Iguaçu, são sugeridas modificações nos curriculos plenos com vistas a um melhor atendimento ao aluno migrante, enquanto sujeito ao processo educativo formal . A criança que migra para a Baixada Fluminense, geralmente, detem um código restrito e depara-se, na escola, com outro semelhante ao seu, utilizado pelo aluno não migrante e com um código elaborado veiculado por aquela instituiçao. Embora se considere o código linguistico um obstáculo de difícil transposição, ao fim de algum tempo, o aluno migrante consegue "imitar" o dos colegas que, tal como ele, integram a população de baixa renda. Já o código difundido pela escola é de dificil absorção pelos seus alunos que nao vivenciam experiências e condutas das classes dominantes que ele procura expressar e caracterizar. No processo de ajustamento e acomodação da criança à sociedade de classes, cabe ao curriculo escolar estabelecer relações de poder e controle expressas nos principios de classificação e emolduramento. A fim de propiciar uma educação voltada para a mudança, os curriculos plenos, muito embora desempenham um papel secundário, devem ser organizados com a participação de representantes de diferentes segmentos da escola buscando preservar valores e traços culturais distintos e estruturados a partir de uma reflexão sobre a realidade.

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This study aimed to provide an insight on the ecology of the bottlenose dolphin population in Madeira archipelago. To achieve this, population structure; group dynamics, site-fidelity, residency and movement patterns within and out of the study area; survival and abundance estimates and spatial and temporal distribution and habitat preferences related to physiographic parameters using data collected between 2001-2011, were investigated. Photo-identification data analysis revealed strong evidences that bottlenose dolphins seen in the archipelago of Madeira belong to an open population with regular recruitment of new animals to the area. This population exhibited a typical fission-fusion society, in which short-term acquaintances prevail, with only a few long-lasting associations. Photo-identification methods demonstrated that there is a large variability in residency pattern, with resident, transient and migrant individuals. Only a small number of dolphins were found to be resident (4.3%). Social network diagram as well as SLAR analysis supported the existence of a mixed population of residents, migrants and transients. Mark-recapture methods estimated a high survival rate, within the range of other long-lived cetacean species. The resident community is composed of app. 180 individuals. In addition, around 400 dolphins of different residency patterns were found to use the south area of Madeira Island. Spatial distribution indicated that bottlenose dolphins were regularly found in shallow and closer to shore areas, suggesting the existence of biological processes influenced by bathymetry. Moreover, temporal patterns revealed no strong seasonal fluctuation in the presence of bottlenose dolphins in Madeira archipelago waters. Bottlenose dolphins are listed under the Annex II of the EU habitats Directive that requires the designation of Special Areas of Conservation (SACs) for this species; as such, the knowledge gained through this work can be used by governmental authorities to the establishment and management of areas for the conservation of bottlenose dolphin in Madeira archipelago.

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The present work has as an objective to seize up some particular meanings of the Feast of Sant Ana (The saint which represents the city of Caicó/RN), a central event of the calendar festive-religious of that city, looking for to perceive on how it combines with the symbolic poles sacred: profane through the social bonds that are present there performed and expressed through the social networking and of local belongings. Such bond ties reveal themselves through a very especial manner, through the migration of returning to the feast, when collectively are produced and updated knowledge and codes that reinforce the representation of the local belonging, nominated as being caicoense . We seek on perceiving how the many events of this feast (from a perspective of a religious order as well as laic) acting on a conclusive way to an identity of the re-meaning of that city, especially in its relation with the migrant natives: the sons and daughters that return to the arms of Sant Ana

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For a long time, we believed in the pattern that tropical and south hemisphere species have high survival. Nowadays results began to contradict this pattern, indicating the need for further studies. Despite the advanced state of the study of bird population parameters, little is known about their variation throughout the year and the factors affecting them. Reproduction, for example, is one factor that may alter adult survival rates, because during this process the breeding pair allocates resources to maintain itself to maintain offspring, making itself more susceptible to diseases and predation. The aim of this study was to estimate survival and population size of a Central and South America passerine, Tachyphonus rufus (Boddaert, 1783), testing hypotheses about the factors that define these parameters. We performed data collection between Nov/2010 and ago/2012 in 12 ha plot, in a fragment of Atlantic Forest in northeastern Brazil. We used capture-mark-recapture methods to generate estimates using Closed Design Robust model in the program MARK. We generated Multi-state models to test some assumptions inherent to Closed Robust Design. The influence of co-variables (time, rain and reproductive cycle) and the effect of transient individuals were measured. Capture, recapture and apparent survival parameters were defined by reproductive cycle, while temporary dispersal was influence by rain. The estimates showed a higher apparent survival during the non-breeding period (92% ± 1%) than during breeding (40% ± 9%), revealing a cost of reproduction and suggesting a trade-off between surviving and reproducing. The low annual survival observed (34%) did not corroborate the pattern of high rates expected for a tropical bird. The largest population size was estimated to be 56 individuals in Nov/11, explained by high recruitment of juveniles, while the lowest observed in May/12: 10 individuals, probably as a result of massive influx of competitor species. Results from this study add to the growing literature on life history of Neotropical species. We encourage studies like this especially in Brazil, where there are few information, and suggest that covariates related to habitat quality and environmental changes should be tested, so that we can generate increasingly reliable models

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Este artigo é uma reflexão sobre o papel que as universidades paulistas e paranaenses desempenham no processo de formação acadêmica dos estudantes dos Países Africanos de Língua Oficial Portuguesa (Palop), em particular os angolanos. Essa formação na instituição de ensino superior propicia novos diálogos e novas sínteses identitárias possibilitadas por outras práticas culturais apreendidas no contato com alunos, docentes, funcionários, instituições acadêmicas e de pesquisa que ignoram a realidade vivenciada por eles em Angola. Constituiremos, assim, o cenário histórico-cultural; o percurso acadêmico e identitário do estudante angolano; o contexto estudantil angolano; a história recente desse país; o lugar do intelectual e do professor universitário; o papel e o uso da língua portuguesa no Brasil e em Angola no ambiente estudantil, familiar e na rua. Buscamos entender o imaginário do jovem estudante intercambista angolano que convive com os conflitos do estigma do migrante temporário e do estereótipo do refugiado de guerra.

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This work was formulated in order to study the use of words in a specific sphere of human communication - the world of music. From a selection of compositions by Luiz Gonzaga (1912 -1989) and partners, the research goes in search of the identity(ies) of the migrant from Brazilian Northeast's "sertão". The work uses a discursive analysis based on a theoretical framework strongly supported by Mikhail Bakhtin's reflections and whose thread is the theme of migration discussed by Zygmunt Bauman. Thus, this qualitative and interpretivist research focuses on a particular type of text, originating from a specific sphere of human communication that is roughly known as "lyrics" ("words of songs")

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The great droughts re- produced spaces in the city of Mossoró / RN in the end of the nineteenth century to the beginning of the twentieth century. Its dimension exceeds the climatic effects becoming social locus when advances over the political and economic sectors, social and cultural of the North / Northeast Brazilian societies during that period. This way, analyzing the re-production of social space in episodes of Mossoró‟s droughts is our toil. So try to reveal each segment, route and aspect of production of space in its size and interface between the perceived, conceived and lived, and subjects related to it - refugees, population and authorities - during the droughts of 1877, 1903 and 1915 within Mossoró city. Therefore, issues such as the constitution and representation of the city and social space in the terrifying experience of the drought of 1877, the production of fixed objects and flows of the urban web through of migrant labor, attempts to control, discipline and spatial planning and ways to resistance to these charges in daily sphere are key issues addressed in this work. For this we use diverse sources as minutes of the city council, reports from provincial presidents, media, memory books and others that sustain us in building our narrative and problematic. This way, the spatial production of Mossoró‟s droughts reveals itself in the field of relations and political-economic transformations and sociocultural, inextricably, that shapes and mobilizes your own social space

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We describe and compare diets of 3 species of vampyrine bats based on analysis of food remains found in gastrointestinal tracts of preserved museum specimens. We also examined possible ontogenetic, intersexual, geographic, and seasonal variations in feeding habits of each species. Trachops cirrhosus fed mainly on insects (79% of prey items), whereas Chrotopterus auritus and Vampyrum spectrum primarily ate small vertebrates (61-73% of prey items for both species). Vertebrate prey most frequently eaten by C. auritus were murid rodents whereas V. spectrum consumed primarily passerine birds. The frequency of occurrence of food items did not differ significantly with age or sex, at least for T. cirrhosus and C. auritus. Significant seasonal variations in diet were observed only for C. auritus, which consumed more insects during the wet season. Our findings confirm the importance of insects in the diet of T. cirrhosus and present new information on a diversified diet for V. spectrum and opportunistic feeding for C. auritus.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Determining the genetic structure of tropical bird populations is important for assessing potential genetic effects of future habitat fragmentation and for testing hypotheses about evolutionary mechanisms promoting diversification. Here we used 10 microsatellite DNA loci to describe levels of genetic differentiation for five populations of the lek-mating blue manakin (Chiroxiphia caudata), sampled along a 414-km transect within the largest remaining continuous tract of the highly endangered Atlantic Forest habitat in southeast Brazil. We found small but significant levels of differentiation between most populations. F-ST values varied from 0.0 to 0.023 (overall F-ST = 0.012) that conformed to a strong isolation by distance relationship, suggesting that observed levels of differentiation are a result of migration-drift equilibrium. N(e)m values estimated using a coalescent-based method were small (<= 2 migrants per generation) and close to the minimum level required to maintain genetic similarity between populations. An implication of these results is that if future habitat fragmentation reduces dispersal between populations to even a small extent, then individual populations may undergo a loss of genetic diversity due to an increase in the relative importance of drift, since inbreeding effective population sizes are relatively small (N-e similar to 1000). Our findings also demonstrate that population structuring can occur in a tropical bird in continuous habitat in the absence of geographical barriers possibly due to behavioural features of the species.

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This study examines the unpalatability of Hyla semilineata tadpoles, relating this possible defence mechanism to their black, presumably aposematic, colouration. Bullfrog tadpoles (Rana catesbeiana), similar in size to the H. semilineata larvae, were used as controls in the experiments. The palatability of H. semilineata tadpoles was tested by offering the tadpoles to Fish (Hoplias malabaricus), free-ranging passerine birds (Pitangus sulphuratus) and hawks (Buteo magnirostris), and domestic chickens (Gallus domesticus). All predators showed a significant preference towards the control R. catesbeiana tadpoles. However, in experiments with fish, this preference was not significant for tadpole capture, only for their ingestion, suggesting that the fish could not distinguish between the two species before tasting them. Although great kiskadees (P. sulphuratus) preferred the control R. catesbeiana tadpoles, they promptly ingested more than half of the test H. semilineata tadpoles when these were offered alone. The chickens, used as naive predators, clearly learned to avoid the black H. semilineata tadpoles after a few trials. The conspicuous colouration and unpalatability of H. semilineata tadpoles may benefit the individual as well as the group, depending on the predator involved.

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Two new genera and five new species of feather mites of the family Proctophyllodidae are described from passerine birds from Brazil: Tyranniphyllodes pitangi gen. n., sp. n. from Pitangus sulphuratus (Tyrannidae); Atrichophyllodes delalandi gen. n., sp. n. from Corythopis delalandi (Tyrannidae); A. mentalis gen. n., sp. n. from Dysithamnus mentalis (Thamnophilidae); Anisophyllodes candango sp. n. from Elaenia chiriquensis (Tyrannidae); and Platyacarus sittasomi sp. n. from Sittasomus griseicapillus (Dendrocolaptidae). The discovery of these taxa might give data for a better understanding of the evolution of the family Proctophyllodidae in general and the dispersion of these mites on passerines in South America in paricular.

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Spermiogenesis of the domestic sparrow was investigated with the light and electron microscopes and a step by step classification is proposed. Three cell populations corresponding to early, mid and late spermatids were easily divided according to their positions in the seminiferous epithelium. In addition to this initial separation, six steps were recognized, based on nuclear morphology and the degree of chromatin condensation, in association to their acrosomal and flagellar development. Early spermiogenesis is the period previous to chromatin condensation. The first step can be recognized by the extending flagellum and the second by the pro-acrosome development in contact with the nucleus. During the third or intermediate step, chromatin condenses and the cell becomes polarized with the pro-acrosomic vesicle and the tail occupying opposite sides of the nucleus. Late spermiogenesis, including steps IV-VI, is marked by complete chromatin condensation. The final cellular modifications lead to the formation of a spiraled spermatozoon. This shape is due to the twisting of the acrosome and nucleus, as well as the helical arrangement of mitochondria around the axoneme along most of the flagellum, making an exceptionally long middle piece. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

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The Pampas deer (Ozotoceros bezoarticus L. 1758) is the most endangered neotropical cervid, and in the past occupied a wide range of open habitats including grassland, pampas, savanna, and cerrado (Brazil) from 5 degrees to 41 degrees S. To better understand the effect of habitat fragmentation on gene flow and genetic variation, and to uncover genetic units for conservation, we examined DNA sequences from the mitochondrial control region of 54 individuals from six localities distributed throughout the present geographical range of the Pampas deer. Our results suggest that the control region of the Pampas deer is one of the most polymorphic of any mammal. This remarkably high variability probably reflects large historic population sizes of millions of individuals in contrast to numbers of fewer than 80 000 today. Gene flow between populations is generally close to one migrant per generation and, with the exception of two populations from Argentina, all populations are significantly differentiated. The degree of gene flow was correlated with geographical distance between populations, a result consistent with limited dispersal being the primary determinant of genetic differentiation between populations. The molecular genetic results provide a mandate for habitat restoration and reintroduction of Pampas deer so that levels of genetic variation can be preserved and historic patterns of abundance can be reconstructed. However, the source of individuals for reintroduction generally should be from populations geographically closest to those now in danger of extinction.