973 resultados para Australia, Chironomidae, continental drift, dispersal, Echinocladius martini, Ferringtonia patagonica, freshwater invertebrate, gene flow, genetic structure, glaciation events, Gondwana, habitat fragmentation, Lars Brundin, Naonella forsythi, New Zealand


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A growing understanding of the ecology of seed dispersal has so far had little influence on conservation practice, while the needs of conservation practice have had little influence on seed dispersal research. Yet seed dispersal interacts decisively with the major drivers of biodiversity change in the 21st century: habitat fragmentation, overharvesting, biological invasions, and climate change. We synthesize current knowledge of the effects these drivers have on seed dispersal to identify research gaps and to show how this information can be used to improve conservation management. The drivers, either individually, or in combination, have changed the quantity, species composition, and spatial pattern of dispersed seeds in the majority of ecosystems worldwide, with inevitable consequences for species survival in a rapidly changing world. The natural history of seed dispersal is now well-understood in a range of landscapes worldwide. Only a few generalizations that have emerged are directly applicable to conservation management, however, because they are frequently confounded by site-specific and species-specific variation. Potentially synergistic interactions between disturbances are likely to exacerbate the negative impacts, but these are rarely investigated. We recommend that the conservation status of functionally unique dispersers be revised and that the conservation target for key seed dispersers should be a population size that maintains their ecological function, rather than merely the minimum viable population. Based on our analysis of conservation needs, seed dispersal research should be carried out at larger spatial scales in heterogenous landscapes, examining the simultaneous impacts of multiple drivers on community-wide seed dispersal networks. (C) 2011 Elsevier Ltd. All rights reserved.

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Gene flow in macroalgal populations can be strongly influenced by spore or gamete dispersal. This, in turn, is influenced by a convolution of the effects of current flow and specific plant reproductive strategies. Although several studies have demonstrated genetic variability in macroalgal populations over a wide range of spatial scales, the associated current data have generally been poorly resolved spatially and temporally. In this study, we used a combination of population genetic analyses and high-resolution hydrodynamic modelling to investigate potential connectivity between populations of the kelp Laminaria digitata in the Strangford Narrows, a narrow channel characterized by strong currents linking the large semi-enclosed sea lough, Strangford Lough, to the Irish Sea. Levels of genetic structuring based on six microsatellite markers were very low, indicating high levels of gene flow and a pattern of isolation-by-distance, where populations are more likely to exchange migrants with geographically proximal populations, but with occasional long-distance dispersal. This was confirmed by the particle tracking model, which showed that, while the majority of spores settle near the release site, there is potential for dispersal over several kilometres. This combined population genetic and modelling approach suggests that the complex hydrodynamic environment at the entrance to Strangford Lough can facilitate dispersal on a scale exceeding that proposed for L. digitata in particular, and the majority of macroalgae in general. The study demonstrates the potential of integrated physical–biological approaches for the prediction of ecological changes resulting from factors such as anthropogenically induced coastal zone changes.

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The Burkholderia cepacia complex (Bcc) is a group of significant opportunistic respiratory pathogens which affect people with cystic fibrosis. In this study, we sought to ascertain the epidemiology and geographic species distribution of 116 Bcc isolates collected from people with CF in Australia and New Zealand. We performed a combination of recA-based PCR, amplified rDNA restriction analysis (ARDRA), pulsed-field gel electrophoresis and repetitive extragenic palindromic PCR on each isolate. Each Burkholderia cenocepacia isolate was also screened by PCR for the presence of the B. cepacia epidemic strain marker. One hundred and fourteen isolates were assigned to a species using recA-based PCR and ARDRA. B. cenocepacia, B. multivorans and B. cepacia accounted for 45.7%, 29.3% and 11.2% of the isolates, respectively. Strain analysis of B. cenocepacia revealed that 85.3% of the isolates were unrelated. One related B. cenocepacia strain was identified amongst 15 people. Whilst full details of person-to-person contact was not available, all patients attended CF centres in Queensland (Qld) and New South Wales (NSW). Although person-to-person transmission of B. cenocepacia strains has occurred in Australia, the majority of CF-related Bcc infections in Australia and New Zealand are most likely acquired from the environment.

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The dispersal process, by which individuals or other dispersing agents such as gametes or seeds move from birthplace to a new settlement locality, has important consequences for the dynamics of genes, individuals, and species. Many of the questions addressed by ecology and evolutionary biology require a good understanding of species' dispersal patterns. Much effort has thus been devoted to overcoming the difficulties associated with dispersal measurement. In this context, genetic tools have long been the focus of intensive research, providing a great variety of potential solutions to measuring dispersal. This methodological diversity is reviewed here to help (molecular) ecologists find their way toward dispersal inference and interpretation and to stimulate further developments.

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Long distance dispersal (LDD) plays an important role in many population processes like colonization, range expansion, and epidemics. LDD of small particles like fungal spores is often a result of turbulent wind dispersal and is best described by functions with power-law behavior in the tails ("fat tailed"). The influence of fat-tailed LDD on population genetic structure is reported in this article. In computer simulations, the population structure generated by power-law dispersal with exponents in the range of -2 to -1, in distinct contrast to that generated by exponential dispersal, has a fractal structure. As the power-law exponent becomes smaller, the distribution of individual genotypes becomes more self-similar at different scales. Common statistics like G(ST) are not well suited to summarizing differences between the population genetic structures. Instead, fractal and self-similarity statistics demonstrated differences in structure arising from fat-tailed and exponential dispersal. When dispersal is fat tailed, a log-log plot of the Simpson index against distance between subpopulations has an approximately constant gradient over a large range of spatial scales. The fractal dimension D-2 is linearly inversely related to the power-law exponent, with a slope of similar to -2. In a large simulation arena, fat-tailed LDD allows colonization of the entire space by all genotypes whereas exponentially bounded dispersal eventually confines all descendants of a single clonal lineage to a relatively small area.

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During November and December 1992 I visited several groups involved with renewable energy, most of them dealing with education. These groups and their work are described briefly in this report. The groups in Melbourne, Australia have come a long way with education in this field and we have a lot to learn from them. Government funding is needed for large scale work, but useful work can still be done at the community level with much smaller budgets.

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This paper explores methodological issues raised by recent attempts to promote the use of health impact assessment (HIA) in Australia and New Zealand. The experiences from both countries are used to highlight important aspects of the debate about the relevance of HIA in appraising both policies and projects particularly in the three broad areas: inclusivity, legitimacy, and method. Many countries are attempting to develop HIA for use in policy development without due consideration of either important methodological issues or the workforce development and capacity-building necessary for its successful implementation.

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The type material of Loxocythere (Loxocythere) ouyenensis (Chapman, 1914) from mid Cenozoic strata of the Mallee Bore No. 11 in the Murray Basin, S.E. Australia is partially redescribed and refigured. This species belongs to a discrete group of large elongate Cenozoic fossil and living Loxocythere species, the carapaces of which possess sub-rectangular inner margin outlines, and broadly rounded posterior extremities. Some much smaller but otherwise very similarly shaped species, that have previously been placed under the genus Microcytherura (i.e. Microcytherura? peterroyi Yassini and Jones, 1995) or the genus Hemiparvocythere Hartmann, 1982 (i.e. Hemiparvocythere Iagunicola Hartmann, 1982), are also known from marine Cenozoic strata and modern seas of the Australasian region. There is a marked difference in the shape of the inner margin between this group of small Australasian forms and European species of Microcytherura s.s .. The former have broadly rounded posterior inner margins, whilst the latter have acutely rounded posterior inner margins. The latter also usually present posterior extremities located well below mid carapace height. It is here argued that this difference in inner margin shape between smaller Australasian species such as Microcytherura? peterroyi, and European species of Microcytherura s.s ., suggests that there is not a direct phylogenetic relationship between these two species groups.

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Universities are increasingly turning to ‘fashionable’ education programs to attract bright, high-quality students to both under-graduate and post-graduate degree programs. Traditional offerings in technology areas, such as Information Systems and Information Technology are being augmented by newer, more marketable degrees in areas such as eCommerce/eBusiness. This paper analyses the eCommerce/eBusiness and Information Systems (IS) / Information Technology (IT) academic programs in Australian and New Zealand universities on the basis of Kotler and Fox's service offering model of educational institutions; and considers what differences exist between these two apparently similar areas of academic endeavour. Finally we look at the trends of academic program delivery in the e-age and question whether universities need to take a more consumer-product approach to the issue of attracting appropriate students.