907 resultados para Life history. MARK. Population parameters. Neotropical birds


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A migration of Helicoverpa punctigera (Wallengren), Heliothis punctifera (Walker) and Agrotis munda Walker was tracked from Cameron Corner (29degrees00'S, 141degrees00'E) in inland Australia to the Wilcannia region, approximately 400 km to the south-east. A relatively isolated source population was located using a distribution model to predict winter breeding, and confirmed by surveys using sweep netting for larvae. When a synoptic weather pattern likely to produce suitable conditions for migration developed, moths were trapped in the source region. The next morning a simulation model of migration using wind-field data generated by a numerical weather-prediction model was run. Surveys using sweep netting for larvae, trapping and flush counts were then conducted in and around the predicted moth fallout area, approximately 400 km to the south-east. Pollen carried on the probosces of moths caught in this area was compared with that on moths caught in the source area. The survey data and pollen comparisons provided evidence that migration had occurred, and that the migration model gave accurate estimation of the fallout region. The ecological and economic implications of such migrations are discussed.

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The Green-striped burrowing frog. Cyclorana alboguttata survives extended drought periods by burrowing underground and aestivating. These frogs remain immobile within cocoons of shed skin and Mucus during aestivation and emerge from their burrows upon heavy rains to feed and reproduce. Extended periods of immobilisation in mammals typically result in muscle atrophy and a decrease in muscle performance. We examined the effect of aestivation and hence prolonged immobilisation, on skeletal Muscle mass. in vitro muscle performance, and locomotor performance in C. alboguttata. Frogs were aestivated in soil for 3 months and were compared with control animals that remained active, were fed, and had a continual supply of water. Compared to the controls, the wet mass of the gastrocnemius. sartorius, gracilus major. semimembranosus. peroneus, extensor cruris, tibialis posticus and tibialis anticus longus of aestivators remained unchanged indicating no muscle atrophy. The in-vitro performance characteristics of the gastroenemius muscle were maintained and burst swimming speed Was Unaffected, requiring no recovery from the extended period of immobilisation associated with aestivation. This preservation of muscle size, contractile condition and locomotor performance through aestivation enables C. alboguttata to compress their life history into unpredictable windows of opportunity, whenever heavy rains occur.

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Hermeneutic Case Reconstruction (Rosenthal, 1993) is a systematic method of analysing biographical self-presentations from an interpretivist perspective. The method consists of five major analytic steps. The first is an analysis of the biographical data that can stand independently of the narrator’s perspective. ‘Objective’ data is extracted from the text or interview transcript and ordered chronologically. Secondly, a thematic field analysis is undertaken in which the data is divided into separate units according to the type of text used, whilst keeping the sequence of these texts units intact. In this step, hypotheses are developed regarding the potential significance of the style and sequence of the events presented. The product of this second step is a reconstruction of the life story. A reconstruction of the life history then follows as the third step. The purpose of this step is to generate hypotheses about the meanings that biographical experiences might have had for the narrator at the time they occurred, given the sociocultural context in which they occurred. In the fourth step, microanalysis of individual text segments is undertaken, in which all hypotheses generated in the earlier steps are tested against the text for support or refutation. The final step consists of a contrastive comparison of the life history and life story. The life story and life history are compared to determine, for example, which aspects of the narrator’s experience have been emphasised or minimised. Through this comparison, the selective process is highlighted. This is referred to as the case structure. This paper describes an application of this method to a published first-person narrative of a woman’s experiences of sustaining a brain injury in a motor vehicle accident.

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Cleaning behaviour has generally been viewed from the cleaner or client's point of view. Few studies, however, have examined cleaning behaviour from the parasites' perspective, yet they are the equally-important third players in such associations. All three players are likely to have had their evolution affected by the association. As cleaner organisms are important predators of parasites, cleaners are likely to have an important effect on their prey. Little, however, is known of how parasites are affected by cleaning associations and the strategies that parasites use in response to cleaners. I examine here what parasites are involved in cleaning interactions, the effect cleaners have on parasites, the potential counter-adaptations that parasites have evolved against the predatory activities of cleaner organisms, the potential influence of cleaners on the life history traits of parasites, and other factors affected by cleaners. I have found that a wide range of ectoparasites from diverse habitats have been reported to interact with a wide range of cleaner organisms. Some of the life history traits of parasites are consistent with the idea that they are in response to cleaner predation. It is clear, however, that although many cleaning systems exist their ecological role is largely unexplored. This has likely been hindered by our lack of information on the parasites involved in cleaning interactions.

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Social bees have a diverse fauna of symbiotic mesostigmatic mites, including highly pathogenic parasites of the honeybee, but there are few reports of Mesostigmata phoretic on or inhabiting the nests of solitary or communal, ground-nesting bees. In south-eastern Australia, however, native bees in the family Halictidae carry what appears to be a substantial radiation of host-specific mesostigmatans in the family Laelapidae. Herein, we redescribe the obscure genus Raymentia , associated with Lasioglossum (Parasphecodes ) spp. bees (Halictidae) and describe two new species, R. eickwortiana from L. lacthium (Smith) and R. walkeriana from L. atronitens (Cockerell). The type species, R. anomala Womersley, is associated with L. altichum (Smith). In addition, we review the mites known to be associated with Australian bees, provide a key to differentiate them, and describe and illustrate acarinaria of the Halictinae. We also report on the first occurrences in Australia of the genera Trochometridium Cross (Heterostigmata: Trochometridiidae), from L. eremaean Walker (Halictidae), and Cheletophyes Oudemans (Prostigmata: Cheyletidae) from Xylocopa Latreille (Xylocopinae), and on the previously unknown association between a Neocypholaelaps Vitzthum (Mesostigmata: Ameroseiidae) and Lipotriches tomentifera (Friese) (Halictidae).

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This article describes an exploratory study that examined the perspectives of practitioners who spend much of their working day listening to and in some ways interpreting for people with severe intellectual disabilities. On the basis of focus group interviews with 23 professional disability-sector workers, including speech therapists, psychologists, and human service workers, the article reports on the importance of a practitioner's values and experience in successful interactions with individuals who rely on self-developed nonsymbolic communication repertoires. The article includes a discussion of the likelihood of including individuals with severe intellectual disabilities in narrative research.

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The moth larva, Doratifera stenosa (Lepidoptera: Limacodidae), was observed feeding voraciously in great numbers on mature leaves of Rhizophora stylosa in mangroves at Port Curtis in Central Queensland, NE Australia. This behaviour was considered unusual since mangroves, and the Rhizophora species in particular, reportedly harbour few herbivores and have relatively low levels of herbivory, less than 10%. During a two year period (1996-1998), larvae were observed consuming around 30-40% of leaves in the canopy each year, and the mangroves appeared able to sustain these high levels of herbivory. The impact on trees was assessed in conjunction with a study of the herbivore, its behaviour and life history, in an attempt to explain the occurrence. Larvae were 1-2 cm in length, bright green and gregarious, with numerous small, stinging hairs along their upper bodies. Feeding was in small cohort groups of 5-70 individuals that broke up immediately prior to each moult after which they regrouped in much larger numbers of mixed cohorts to form single-file processions across branches, stems and prop roots. In this way, they moved to neighbouring trees with less affected foliage. One of the outstanding characteristics of this herbivore was its ability to desist from killing host trees although it appeared quite capable of doing so had it remained on individual trees. By moving from tree to tree, the herbivore was able to heavily crop Rhizophora foliage in an apparently sustainable manner. These findings demonstrate the role and importance of foliar herbivory in severely affected forests and how such instances best not be ignored or treated as curiosities in future assessments of herbivory and forest turnover in mangrove ecosystems.

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Semi-aquatic animals represent a transitional locomotor condition characterised by the possession of morphological features that allow locomotion both in water and on land. Most ecologically important behaviours of crocodilians occur in the water, raising the question of whether their 'terrestrial construction' constrains aquatic locomotion. Moreover, the demands for aquatic locomotion change with life-history stage. It was the aim of this research to determine the kinematic characteristics and efficiency of aquatic locomotion in different-sized crocodiles (Crocodylus porosus). Aquatic propulsion was achieved primarily by tail undulations, and the use of limbs during swimming was observed only in very small animals or at low swimming velocities in larger animals. Over the range of swimming speeds we examined, tail beat amplitude did not change with increasing velocity, but amplitude increased significantly with body length. However, amplitude expressed relative to body length decreased with increasing body length. Tail beat frequency increased with swimming velocity but there were no differences in frequency between different-sized animals. Mechanical power generated during swimming and thrust increased non-linearly with swimming velocity, but disproportionally so that kinematic efficiency decreased with increasing swimming velocity. The importance of unsteady forces, expressed as the reduced frequency, increased with increasing swimming velocity. Amplitude is the main determinant of body-size-related increases in swimming velocity but, compared with aquatic mammals and fish, crocodiles are slow swimmers probably because of constraints imposed by muscle performance and unsteady forces opposing forward movement. Nonetheless, the kinematic efficiency of aquatic locomotion in crocodiles is comparable to that of fully aquatic mammals, and it is considerably greater than that of semi-aquatic mammals.

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The Wollemi pine, Wollemia nobilis (Araucariaceae), was discovered in 1994 as the only extant member of the genus, previously known only from the fossil record. With fewer than 100 trees known from an inaccessible canyon in southeastern Australia, it is one of the most endangered tree species in the world. We conducted a comparative population genetic survey at allozyme, amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) loci in W. nobilis, Araucaria cunninghatnii and Agathis robusta - representatives of the two sister genera. No polymorphism was detected at 13 allozyme loci, more than 800 AFLP loci or the 20 SSR loci screened in W. nobilis. In Ag. robusta only one of 12 allozyme loci, five of 800 AFLP loci and none of the 15 SSR loci were variable. For A. cunninghamii, 10 of > 800 AFLP loci and five of 20 SSR loci were variable. Thus low genetic diversity characterizes all three species. While not ruling out the existence of genetic variation, we conclude that genetic diversity is exceptionally low in the Wollemi pine. To our knowledge this is the most extreme case known in plants. We conclude that the combination of small population effects, clonality and below-average genetic variation in the family are probable contributing factors to the low diversity. The exceptionally low genetic diversity of the Wollemi pine, combined with its known susceptibility to exotic fungal pathogens, reinforces current management policies of strict control of access to the pines and secrecy of the pine locations.

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We investigated the oviposition preference and larval performance of Helicoverpa armigera under laboratory conditions to determine if the oviposition preference of individual females on maize, cowpea and cotton correlates with offspring performance on the leaves of the same host plants. The host-plant preference hierarchy of females did not correlate with their offspring performance. Female moths chose host plants that contributed less to their offspring fitness. Plant effects accounted for the largest amount of variation in offspring performance, while the effects of female (family) was low. The offspring of most females (80%, n = 10) were broadly similar, but 20% (two out of 10), showed marked difference in their offspring performance across the host-plant species. Similarly, there was no relation between larval feeding preference and performance. However, like most laboratory experiments, our experi-mental design does not allow the evaluation of ecological factors (for example, natural enemies, host abundance, etc.) that can play an important role in larval performance in the field. Overall, the results highlight the importance of carrying out preference performance analysis on the individual or family level, rather than pooling individuals to obtain average population data.

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O presente trabalho aborda, sob uma perspectiva analítica e crítica da Geografia, a temática relacionada ao lazer na cidade contemporânea, tendo como problemática a implantação desigual dos equipamentos públicos de lazer na cidade de Vitória-ES. A discussão do tema está associada ao lazer como um direito constitucional do cidadão, revelando de que maneira o Poder Público corrobora para a espacialização desigual dos equipamentos de lazer na cidade estudada. A discussão surgiu em torno da constatação de que Vitória-ES é uma cidade geograficamente dividida pelo Maciço Central, o que gera espaços diferenciados, como a orla Nordeste, rica e equipada dos mais diversos equipamentos de lazer e a orla Noroeste, voltada para a baía de Vitória e para o manguezal, marcada por grandes disparidades humanas, econômicas e sociais. Observou-se que, durante muitas décadas, o Poder Público esteve ausente na promoção de equipamentos públicos de lazer na orla Noroeste de Vitória, o que gerou ambientes diferenciados na cidade. Enquanto isso, a orla Nordeste passou por um intenso processo de promoção de equipamentos públicos, dos mais requintados, promotores de um valorização do solo local e da melhoria da qualidade de vida para a população ali residente. Desse modo, a dissertação pretendeu investigar as políticas públicas que estiveram atreladas à promoção de equipamentos públicos de lazer em quatro bairros específicos: Grande Vitória, Nova Palestina, Maria Ortiz e Resistência, todos localizados na orla Noroeste de Vitória. A escolha pelos bairros se deu através da detecção de que dois deles (Maria Ortiz e Nova Palestina) receberam a implantação de equipamentos públicos de lazer, tendo suas orlas reurbanizadas e o outros dois (Grande Vitória e Resistência), até a presente data, aguardam pela chegada de infraestrutura urbana de todos os tipos, inclusive de lazer.

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A dissertação aborda a fragilização dos espaços públicos num contexto de utilização de câmeras de vigilância, temática que será problematizada a partir da vigilância exercida pelas câmeras do município de Vila Velha – ES. Partimos da hipótese de que vivemos cercados por objetos técnicos que continuamente produzem informações sobre os sujeitos sociais e os seus espaços como forma de controle. As câmeras representam o exemplo mais conhecido desses objetos, embora sejam apresentadas pelos discursos das administrações públicas como ferramentas de auxílio à segurança. Utilizando como metodologia a observação participante para acompanhamento do trabalho realizado “por trás” das câmeras, concluímos que uma série de fatores desmistificam esses discursos: as câmeras que não são monitoradas, a ausência de manutenção dos equipamentos do sistema, os baixos salários e as condições trabalhistas daqueles que operam as câmeras, a ausência de articulação com os demais setores da prefeitura, a falta de credibilidade das câmeras com a polícia, etc. Por outro lado, ao fazermos um trabalho “na frente” das câmeras, observando o cotidiano de três áreas vigiadas nos bairros Praia da Costa, Glória e Riviera da Barra, bem como entrevistando transeuntes, moradores e comerciantes, concluímos que a maneira surpreendentemente indiferente com que as pessoas lidam com a vigilância é alimentada quando descobrimos que elas não oferecem a segurança pretendida. Se as câmeras não auxiliam a segurança pública, a sua utilização tem um efeito perverso na fragilização dos espaços públicos de Vila Velha, considerando que a vigilância representa ameaças potenciais e reais às condições que o pressupõem: a pluralidade e a liberdade, pois as câmeras atualizam um estado de vigilância permanente alimentando o estigma sobre determinados grupos sociais, que, por sua vez, são os alvos favoritos da vigilância, o que permite às câmeras, ainda, a potencial função de controle socioespacial direto (função admitida inclusive pelos cidadãos entrevistados) sobre os espaços vigiados; e a individualidade dos cidadãos, que é acintosamente violada. As câmeras, portanto, ao pretenderem garantir qualidade de vida à população (oferecendo segurança), produzem o efeito exatamente inverso

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O objetivo deste estudo foi estimar a cronologia e sequência de erupção da dentição decídua e seus fatores relacionados em amostra de crianças de duas regiões do município de Vitória, ES. Os dados utilizados no estudo são provenientes de um estudo longitudinal realizado entre 2003 e 2006 com 86 recém-nascidos que foram acompanhados até a idade de 36 meses de vida, cuja coleta de dados foi obtida por meio da aplicação de um formulário as mães e da realização de um exame clínico nas crianças. Um total de 67 crianças permaneceram até o final do estudo. Calculou-se a idade média de erupção dos dentes decíduos de cada criança e foram aplicados o teste de kappa, McNemar e kappa ajustado pela prevalência. Em seguida realizou-se a Análise de Sobrevivência. Os resultados mostraram que a média de erupção dos dentes decíduos variou de oito a 29 meses de vida no arco inferior, e de 11 a 30 meses no arco superior e que os maiores níveis de concordância foram para os tempos de erupção dos incisivos e caninos decíduos (71/81, kappa = 0,82; IC95% = 0,72-0,93; 53/63, kappa = 0,76; IC95% = 0,62-0,88) do que para os molares decíduos. Dos fatores relacionados a cronologia de erupção da dentição decídua, foi identificado na Regressão de Cox que os hábitos alimentares infantis podem influenciar, acelerando e retardando esse processo eruptivo. Recomenda-se o conhecimento do perfil de erupção decídua de cada população para que tais evidências sirvam de base para a implementação de medidas de prevenção e controle da saúde dessa população e auxilie na elaboração de estratégias, com ações de proteção e promoção da saúde. As ações tem como finalidade a prevenção de possíveis alterações bucais e gerais durante o crescimento e desenvolvimento infantil e melhoria da qualidade de vida dessa população.

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Una de las potencialidades del arte es devenir una herramienta para enfocar determinados conflictos desde nuevos ángulos y articular preguntas que impacten en la comunidad. Aquí el arte se funde con la filosofía, la sociología, la antropología, con el activismo, y con la propia vida. A partir de tales parámetros, se esbozarán diversas propuestas artísticas que ilustran cómo distintos creadores abordan –desde distintos ángulos– el fenómeno de la migración Dentro de la amplia miríada de perspectivas desde las que se puede tratar la migración es interesante resaltar el trabajo de varios artistas que se transforman en altavoces de las experiencias de otras personas, tal y como ejemplifican los proyectos de Pep Dardanyà, Marisa González, He Chengyue y Josep María Martín. Desde un ángulo radicalmente distinto, Santiago Sierra y el colectivo Yes lab reproducen y llevan al límite las mismas dinámicas de explotación que critican, y para finalizar, bajo el prisma de la experiencia vivida, la artista Fiona Tan explora su propio proceso migratorio e investiga la construcción de la identidad.