69 resultados para 590 Animals (Zoology)

em Deakin Research Online - Australia


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Locomotion is one of the major energetic costs faced by animals and various strategies have evolved to reduce its cost. Birds use interspersed periods of flapping and gliding to reduce the mechanical requirements of level flight while undergoing cyclical changes in flight altitude, known as undulating flight. Here we equipped free-ranging marine vertebrates with accelerometers and demonstrate that gait patterns resembling undulating flight occur in four marine vertebrate species comprising sharks and pinnipeds. Both sharks and pinnipeds display intermittent gliding interspersed with powered locomotion. We suggest, that the convergent use of similar gait patterns by distinct groups of animals points to universal physical and physiological principles that operate beyond taxonomic limits and shape common solutions to increase energetic efficiency. Energetically expensive large-scale migrations performed by many vertebrates provide common selection pressure for efficient locomotion, with potential for the convergence of locomotory strategies by a wide variety of species.

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Migratory animals are simultaneously challenged by the physiological demands of long-distance movements and the need to avoid natural enemies including parasites and pathogens. The potential for animal migrations to disperse pathogens across large geographic areas has prompted a growing body of research investigating the interactions between migration and infection. However, the phenomenon of animal migration is yet to be incorporated into broader theories in disease ecology. Because migrations may expose animals to a greater number and diversity of pathogens, increase contact rates between hosts, and render them more susceptible to infection via changes to immune function, migration has the potential to generate both "superspreader species" and infection "hotspots". However, migration has also been shown to reduce transmission in some species, by facilitating parasite avoidance ("migratory escape") and weeding out infected individuals ("migratory culling"). This symposium was convened in an effort to characterize more broadly the role that animal migrations play in the dynamics of infectious disease, by integrating a range of approaches and scales across host taxa. We began with questions related to within-host processes, focusing on the consequences of nutritional constraints and strenuous movement for individual immune capability, and of parasite infection for movement capacity. We then scaled-up to between-host processes to identify what types, distances, or patterns of host movements are associated with the spread of infectious agents. Finally, we discussed landscape-scale relationships between migration and infectious disease, and how these may be altered as a result of anthropogenic changes to climate and land use. We are just beginning to scratch the surface of the interactions between infection and animal migrations; yet, with so many migrations now under threat, there is an urgent need to develop a holistic understanding of the potential for migrations to both increase and reduce infection risk.

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Childhood cruelty to animals may be a marker of poor prognosis amongst conduct disordered children. However, other than semistructured interviews with parents or children, there are no screening instruments for this behavior. The aim of this study was to develop such an instrument. In the first phase of the study, a parent-report questionnaire, Children's Attitudes and Behaviors Towards Animals (CABTA) was designed and piloted on 360 elementary school children, enabling community norms and a factor structure for the instrument to be derived. In the second phase, the questionnaire was completed by the parents of a small sample of children (N= 17) to establish its test-retest reliability. In the third phase of the study, the CABTA was completed by the parents of 19 children who had been diagnosed with either a Disruptive Behavioral Disorder or Attention Deficit Hyperactivity Disorder, and the results were compared with the outcome of a semistructured interview with parents regarding their child's behavior toward animals. The results of the various phases of the study indicated that the CABTA consists of two factors, Typical and Malicious Cruelty to animals, and is a reliable and valid tool for detecting childhood cruelty to animals. Possible use and adaptations of the CABTA as a screening instrument in clinical and community samples are discussed.

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Urban climates are known to differ from those of the surrounding rural areas, as human activities in cities lead to changes in temperature, humidity and wind regimes. These changes can in turn affect the geographic distribution of species, the behaviour of animals and the phenology of plants. The grey-headed flying-fox (Pteropus poliocephalus) is a large, nomadic bat from eastern Australia that roosts in large colonies known as camps. Historically a warm temperate to tropical species, P. poliocephalus recently established a year-round camp in the Royal Botanic Gardens Melbourne. Using a bioclimatic analysis, we demonstrated that on the basis of long-term data, Melbourne does not fall within the climatic range of other P. poliocephalus camp sites in Australia. Melbourne is drier than other summer camps, and cooler and drier than other winter camps. The city also receives less radiation, in winter and annually, than the other summer and winter camps of P. poliocephalus. However, we found that temperatures in central Melbourne have been increasing since the 1950s, leading to warmer conditions and a reduction in the number of frosts. In addition, artificial watering of parks and gardens in the city may contribute the equivalent of 590 mm (95% CI: 450–720 mm) of extra rainfall per year. It appears that human activities have increased temperatures and effective precipitation in central Melbourne, creating a more suitable climate for camps of the grey-headed flying-fox. As demonstrated by this example, anthropogenic climate change is likely to complicate further the task of conserving biological diversity in urban environments.

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How powerful are our categories? Some might see these three poets in the categories ``working-class man'', ``indigenous man'', ``educated woman''. But what does this mean? Could they not all be educated, indigenous, working-class? There are sound reasons to think in categories, but poets are implicitly against theory, since each has a peculiar source of poetic power. Even if that turns out to be gender or class or race, it will be more complex than those over-burdened words allow. Poems, like poets, resist classification and gaze back at us like imaginary animals, indifferent to zoology

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In Western research, cruelty to animals in childhood has been associated with comorbid conduct problems and with interpersonal violence in later life. However, there is little understanding of the etiology of cruelty to animals, and what in the child's life may require attention if the chain linking animal cruelty and later violence is to be broken. The study reported in this paper investigated the association between parent-reported cruelty to animals, and parent- and self-reported psychological strengths and weaknesses in a sample of 379 elementary school children in an Eastern context, Malaysia. No gender differences were found in relation to cruelty to animals or psychological problems, as assessed with the Strengths and Difficulties Questionnaire (SDQ). However, there were different predictors of cruelty to animals for boys and girls. Regression analyses found that for boys, parent-reported hyperactivity was a unique predictor of Malicious and Total Cruelty to animals. For girls, self-reported conduct problems was a unique predictor of Typical Cruelty to animals. Parent-reported total difficulties were associated with Typical, Malicious, and Total Cruelty to animals. We suggest that routine screening of children with an instrument such as the SDQ may help to detect those children who may need to undergo further assessment and perhaps intervention to break the chain linking childhood cruelty to animals and later conduct problems.

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When older people enter residential care facilities, disruption to social networks may occur, with detrimental effects on health and wellbeing. This article reports on a study undertaken in an aged care facility in Melbourne, Australia, that explored the potential for a visiting companion animal programme to improve the health and wellbeing of residents and to promote their capacity for building relationships. Results back assertions in the literature that companion animals foster relationships by giving people opportunities to interact with others, but further study is needed to verify the link

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Childhood cruelty to animals is a symptom of conduct disorder that has been linked to the perpetration of violence in later life. Research has identified several factors associated with its etiology, including social factors. However, no cross-cultural studies on this phenomenon have been reported. This study investigated childhood cruelty to animals in Japan, Australia and Malaysia. Parents of 1,358 children between the ages of 5 and 13 years completed the Children’s Attitudes and Behaviours towards Animals questionnaire (CABTA) which assesses Typical and Malicious Cruelty to animals. Analyses revealed no overall differences between children from these countries on either scale. However, younger boys were more likely to be cruel than younger girls in each country, and younger children in Australia and Japan were more likely to be cruel that older children in those countries. The findings are discussed in relation to previous research, and recommendations for future studies are suggested.

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Maximum life span differences among animal species exceed life span variation achieved by experimental manipulation by orders of magnitude. The differences in the characteristic maximum life span of species was initially proposed to be due to variation in mass-specific rate of metabolism. This is called the rate-of-living theory of aging and lies at the base of the oxidative-stress theory of aging, currently the most generally accepted explanation of aging. However, the rate-of-living theory of aging while helpful is not completely adequate in explaining the maximum life span. Recently, it has been discovered that the fatty acid composition of cell membranes varies systematically between species, and this underlies the variation in their metabolic rate. When combined with the fact that 1) the products of lipid peroxidation are powerful reactive molecular species, and 2) that fatty acids differ dramatically in their susceptibility to peroxidation, membrane fatty acid composition provides a mechanistic explanation of the variation in maximum life span among animal species. When the connection between metabolic rate and life span was first proposed a century ago, it was not known that membrane composition varies between species. Many of the exceptions to the rate-of-living theory appear explicable when the particular membrane fatty acid composition is considered for each case. Here we review the links between metabolic rate and maximum life span of mammals and birds as well as the linking role of membrane fatty acid composition in determining the maximum life span. The more limited information for ectothermic animals and treatments that extend life span (e.g., caloric restriction) are also reviewed.

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There has been growing interest in linking the learning of Science with the literacies of Science and representations. Recent attention has been focused on learning theories that emphasise the socio-cultural and situated aspects of learning, and in particular the notion of learning as participation in a discourse community. This paper will describe a learning sequence planned wilh Year 5/6 teachers to study invertebrates in the schoolground environment, but with an additional focus in which students generated and negotiated representations, and discussed the adequacy of these. The paper will present data from video capture of classroom activities, students' work samples, and pre- and post-unit testing, to explore what a representational focus might entail in teaching science, and the role of representations in learning, reasoning and exploring in science.

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Drawing on studies of humans, rodents, birds and arthropods, I show that 'cognitive maps' have been used to describe a wide variety of spatial concepts. There are, however, two main definitions. One, sensu Tolman, O'Keefe and Nadel, is that a cognitive map is a powerful memory of landmarks which allows novel short-cutting to occur. The other, sensu Gallistel, is that a cognitive map is any representation of space held by an animal. Other definitions with quite different meanings are also summarised. I argue that no animal has been conclusively shown to have a cognitive map, sensu Tolman, O'Keefe and Nadel, because simpler explanations of the crucial novel short-cutting results are invariably possible. Owing to the repeated inability of experimenters to eliminate these simpler explanations over at least 15 years, and the confusion caused by the numerous contradictory definitions of a cognitive map. I argue that the cognitive map is no longer a useful hypothesis for elucidating the spatial behaviour of animals and that use of the term should be avoided.

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This paper explores the role and percept¡ons of an¡mals in internat¡onal development efforts and the possible contradictions between differing priorities of agencies involved in internat¡onal charitable efforts. The description ofthe differing descriptions of purposes in the (England and Wales) Charities Act of 2006 prov¡des a good starting point. There are many available purposes for charities, and although having one purpose does not preclude a second, organizations concerned with animal welfare appear to be quite d¡stinct from those work¡ng for poverty alleviation in the developing world. A fun and novel gift of a donkey may equally be perceived as a cruel, environmentally unsustainable and misguided development effort, a valuable asset for a household, or a burden to a household struggling to feed existing mouths..... This paper questions the underlying tensions between human development, animal welfare, and poverty alleviation exploring cultural tensions, philosophical tens¡ons and where areas of common ground may be found.