RESUMO
Few chloroplast-based genetic studies have been undertaken for plants of mesic temperate forests in the southern hemisphere and fossil-based models have provided evidence of vegetation history only at the broadest scales in this region. This study investigates the chloroplast DNA phylogeography of Tasmannia lanceolata (Winteraceae), a fleshy-fruited, bird-dispersed shrub that is widespread in the mountains of southeastern Australia and Tasmania. Thirty haplotypes were identified after sequencing 3206 bp of chloroplast DNA in each of 244 individuals collected across the species' range. These haplotypes showed unexpectedly strong phylogeographic structuring, including a phylogeographic break within a continuous part of the species' range, with the distribution of four major clades mostly not overlapping, and geographic structuring of haplotypes within these clades. This strong geographic patterning of chloroplast DNA provided evidence for the survival of T. lanceolata in multiple putative wet forest refugia as well as evidence for additional wet forest species refugia in southeastern Australia. In western Tasmania lower haplotype diversity below the LGM tree line compared to above the LGM tree line suggests that glacial refugia at high altitudes may have been important for T. lanceolata. The level of geographic structuring in T. lanceolata is similar to gravity dispersed southern hemisphere plants such as Nothofagus and Eucalyptus. Behavioural traits of the birds transporting seed may have had a strong bearing on the limited transport of T. lanceolata seed, although factors limiting establishment, possibly including selection, may also have been important.
Assuntos
Evolução Molecular , Filogenia , Winteraceae/genética , Animais , Austrália , Aves , DNA de Cloroplastos/genética , DNA de Plantas/genética , Geografia , Haplótipos , Análise de Sequência de DNA , TasmâniaRESUMO
OBJECTIVE: To identify potential health effects of the greenhouse effect and ozone layer depletion in Australia. DATA SOURCES: Data were derived from a number of sources: (i) published articles accessed from relevant databases in the disciplines of health, public health and climatology over the past 20 years; (ii) published conference proceedings, review monographs and government reports covering the topic; (iii) a survey of experts in public health and climatology/geography (150 individuals were surveyed in the first phase with a 63% response rate); and (iv) a consensus conference in which 22 invited experts reviewed the results of the literature review and survey and a second conference in which 18 senior members of the health bureaucracy and public health profession considered the implications of the findings. STUDY SELECTION: Over 200 published articles or monographs were reviewed. Criteria for selection were whether the papers contributed information to the objectives of the review. DATA EXTRACTION: Because of the nature of the problem under investigation, predictions based on reasonable scientific assumptions were the major content of the review rather than conclusions based on scientific research. DATA SYNTHESIS: The major predicted health effects of long-term climatic change in Australia are skin and eye damage from increased ultraviolet radiation exposure, increased incidence of some respiratory diseases, vector-borne and water-borne diseases, and the social and physical effects of natural hazards and social and economic restructuring. The most vulnerable groups include the aged, the very young, the chronically ill, those living in poorly designed neighbourhoods and those working in outdoor occupations or heavy industry. CONCLUSIONS: The potential effects on health of long-term climatic change cover the broad spectrum of public health concerns. Detailed predictions of likely problems in specific geographic areas are not yet possible, but progressive development of such predictive capability is a high priority. Doctors will have an increasingly important role in monitoring local health status and participating in disease prevention and surveillance programmes.