Genetic Divergence for the Amphibian Pleurodeles waltl in Southwest Portugal: Dispersal Barriers Shaping Geographic Patterns

Dispersal and vicariance are the principal mechanisms responsible for the formation of biogeographic patterns, driven or maintained by the role of past and current barriers to dispersal. Southwest Portugal harbors a rich endemic fauna and flora where strongly differentiated taxa can be observed, suggesting ancient isolating mechanisms acted in this region. In this study, we used information from two partial mitochondrial sequences, combined with information from microsatellite loci and amplification success, to investigate biogeographic patterns of genetic divergence in populations of Pleurodeles waltl in Portugal. Our results demonstrate genetic differentiation at different time frames creating distinct populations in southwest Portugal, which might have arisen following isolation by a large river estuary and mountainous barriers. Habitat destruction associated with agricultural intensification raises conservation concerns over the unique biodiversity in this region.Fundacao para a Ciencia e Tecnologia (Portugal); FEDER [PTDC/BIA-BDE/68730/2006, SFRH/BD/24064/2005

Changes in dewpond numbers and amphibian diversity over 20 years on chalk downland in

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Population structure and its implications for conservation of the great silver beetle Hydrophilus piceus in Britain

1. The great silver water beetle Hydrophilus piceus is one of the largest aquatic insects in Europe. In Britain it is rare and endangered, and confined to a small number of low-lying marshes. Very little is known about the beetle populations in any of these areas, or the connectivity between them

Amphibian Declines Are Not Uniquely High amongst the Vertebrates: Trend Determination and the British Perspective

Although amphibians have experienced major global declines and an increasing extinction rate, recent results indicate that they are not as uniquely disadvantaged as previously supposed. Acquisition of robust data is evidently crucial to the determination of both absolute and relative rates of biodiversity declines, and thus in prioritising conservation actions. In Britain there is arguably a longer history of recording, and attempting to conserve, a wide range of species groups than anywhere else in the world. This stems from the early activities of Victorian naturalists in the nineteenth century, the establishment of natural history societies and, since the mid-twentieth century, a range of national recording schemes and organisations actively involved in conservation. In this review we summarise comparative evidence for British amphibians and reptiles concerning historical abundance, population trends and their causes, and outline how they relate to the situation elsewhere in Europe (and possibly the World). We discuss possible reasons why the plight of ectothermic vertebrates (fish, amphibians and reptiles) seems generally worse than that of endotherms (birds and mammals), as well as research priorities and factors likely to impact amphibians and reptile conservation in future

Buccal swabbing as a source of DNA from squamate reptiles

Abstract Buccal swabbing was compared with other tissues as a source of DNA for microsatellite genotyping from two squamate reptiles. For both species, the lizard Lacerta agilis and the snake Coronella austriaca, buccal swabbing proved more reliable than tissues including tail tips, toe clips and ventral scale clips

Buccal swabbing as a source of DNA from squamate reptiles

Buccal swabbing was compared with other tissues as a source of DNA for microsatellite genotyping from two squamate reptiles. For both species, the lizard Lacerta agilis and the snake Coronella austriaca, buccal swabbing proved more reliable than tissues including tail tips, toe clips and ventral scale clips

Ronald Maxwell Savage, 1900-1985: a tribute

No description supplie

Ronald Maxwell Savage, 1900-1985: a tribute

No description supplie

Intraspecific competition disadvantages inbred natterjack toad (Bufo calamita) genotypes over outbred ones in a shared pond environment

1. We carried out a replicated pond experiment to compare the viabilities of natterjack toad Bufo calamita embryos and larvae from inbred and outbred populations. Surviving genotypes were identified at the end of the experiment using fixed diagnostic alleles at a microsatellite locus. 2. Inbred larvae grew more slowly than outbred larvae and in mixed populations the survival of outbred larvae was three- to 10-fold higher than that of inbred larvae. 3. Larval mortality correlated with the abundance of dytiscid water beetles, and was therefore probably caused mainly by predation. The relatively higher rate of mortality of inbred larvae was in turn due probably to lower growth rates delaying achievement of a size refuge. 4. Intraspecific competition may help to purge inbred individuals in populations with mixed levels of inbreeding. The significance of inbreeding with relatively cryptic effects, such as reduction in amphibian larval growth rate, is discussed with respect to population viability