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Biogeographic boundaries are characterised by distinct faunal and floral assemblages restricted on either side, but patterns among groups of taxa often vary and may not be discrete. Historical biogeography as a consequence, while providing crucial insights into the relationship between biological diversity and earth history, has some limitations. Patterns of intraspecific molecular variation, however, may show unambiguous evidence for such historical divides, and can be used to test competing biogeographic hypotheses (often based on the dispersal-vicariance debate). Here, we utilise this method to test the hypothesis that a major biogeographic transition zone between the Sundaic and Indochinese biotas, located just north of the Isthmus of Kra in SE Asia, is the result of Neogene marine transgressions that breached the Isthmus in two locations for prolonged periods of time (>1 million year duration). Phylogeographic analyses of a freshwater decapod crustacean, the giant freshwater prawn Macrobrachium rosenbergii, strongly supports the historical existence of the more northerly postulated seaway. Results presented here highlight the power of utilising intraspecific molecular variation in testing biogeographical hypotheses.Heredity (2005) 94, 370-378. doi:10.1038/sj.hdy.6800613 Published online 3 November 2004 [ABSTRACT FROM AUTHOR]

Abstract The wild rabbit (Oryctolagus cuniculus L.) is a significant pest in arid and semi-arid Australia, where erratic rainfall and irregular pasture growth cause population sizes to oscillate, increasing virtually without limit and then crashing during drought conditions. Vacant habitat patches can be rapidly recolonized from nearby patches in high rainfall years. Using two adjoining rabbit population systems in arid and semi-arid south-west Queensland, this study evaluates patterns of population differentiation and proposes a mechanism that may lead to the formation of multiple rabbit population systems in the same locality. Using the combined haplotype frequency data from both a local and regional study, estimates of genetic exchange among local populations are considered in conjunction with ecological data to evaluate the significance of habitat attributes (and their spatial distribution) on the local distribution of rabbit populations, both within and between two adjacent population systems. A tentative model is proposed to explain the observed differences in population structure between the two adjoining systems. Under this model, population structure at specific locations is determined primarily by the availability of areas suitable for prolonged colonization and the quality of the intervening habitat that dictates the degree of isolation between locations and therefore the probability of recolonization following local extinctions. It is also suggested that the current rabbit distribution may be a function of the flexibility of behavioural responses in rabbits to the level of spatial heterogeneity of favourable habitats within the two regions. [ABSTRACT FROM AUTHOR]

For the first time, the UK Criminal Justice Act (1991) allowed the videotaped evidence of a child to be substituted for the child's evidence-in-chief in a criminal court. The present study is an evaluation of that legislation. One hundred and fifty children were observed testifying in a criminal court in the UK. The use of the videotaped evidence and subsequent cross-examination of the child witness (usually via the closed circuit television system) was also observed. The data base from the Lord Chancellor's Department of all trials involving child witnesses in England and Wales was also analysed. The results showed that the introduction of the video technology into the criminal courts reduced the levels of stress of child witnesses but did not increase the conviction rates. [ABSTRACT FROM AUTHOR]

+ E spectra derived from the non-decomposing anion of some sulphur compounds are independent of the pressure of the collision gas. The compounds chosen for study contain peaks produced from either ortho effects or skeletal rearrangement fragments in their conventional positive ion spectra. The dissociative + E spectra are either devoid of skeletal rearangement ions or alternatiely contain such peaks in small abundance. In contrast, peaks derived from ortho reactions are present in high abundance. [ABSTRACT FROM AUTHOR]