A 5-year mark-recapture study of smooth snakes (Coronella austriaca) in the Carnic Alps (1100 m above sea level) of north-eastern Italy provided extensive information on the biology and life-history of these small viviparous snakes. Offspring were relatively large (mean=15 cm total length, 2.9 g) when they were born in late summer, and females grew to maturity (44 cm, 50 g) in approximately 4 years. Larger neonates retained their size advantage for at least 12 months, but did not have a higher probability of survival. Although sexual size dimorphism (at birth and at mean adult body sizes) was minor, the sexes differed significantly in several respects. Females grew faster than males during juvenile life, and adult females diverged in dietary habits from the rest of the population. Whereas juveniles (of both sexes) and adult males fed primarily on lizards, larger females shifted to feeding less frequently, but taking larger prey (mammals and snakes). Reproductive output increased strongly with maternal body size: larger females reproduced more frequently, produced larger litters of larger neonates, had higher relative clutch masses (RCMs), and had a lower proportion of stillborn off-spring. Most females produced a litter every 2nd or 3rd year. We did not detect significant year-to-year variation in reproductive traits over the 5 years of our study. Females were consistent from one litter to the next in several traits (e.g., litter sizes, offspring sizes and shapes, proportions of stillborn neonates, RCMs), but this consistency was due to differences in body size among females rather than to size-independent maternal effects. Overall litter sex ratios averaged 50/50, but sex ratios tended to be more male-biased in litters that were unusually large relative to maternal body size, and in litters containing a high proportion of stillborn offspring. "Costs" of reproduction appear to be high in this population, in terms of both energy allocation and risk. Reproduction reduced growth rates, and females that recovered condition more quickly in the year after reproduction were able to reproduce again after a briefer delay. Mortality was highest in reproducing females with high RCMs, and in females that were very emaciated after parturition. The marked increase in reproductive output with increasing maternal body size in C. austriaca may reflect a reduction in "costs" as females grow larger, and the dietary shift to larger prey may enhance the rate that females can accumulate energy for reproduction.

We identified hotspots of terrestrial vertebrate species diversity in Europe and adjacent islands. Moreover, we assessed the extent to which by the end of the 21st century such hotspots will be exposed to average monthly temperature and precipitation patterns which can be regarded as extreme if compared to the climate experienced during 1950-2000. In particular, we considered the entire European sub-continent plus Turkey and a total of 1149 species of terrestrial vertebrates. For each species, we developed species-specific expert-based distribution models (validated against field data) which we used to calculate species richness maps for mammals, breeding birds, amphibians, and reptiles. Considering four global circulation model outputs and three emission scenarios, we generated an index of risk of exposure to extreme climates, and we used a bivariate local Moran’s I to identify the areas with a significant association between hotspots of diversity and high risk of exposure to extreme climates. Our results outline that the Mediterranean basin represents both an important hotspot for biodiversity and especially for threatened species for all taxa. In particular, the Iberian and Italian peninsulas host particularly high species richness as measured over all groups, while the eastern Mediterranean basin is particularly rich in amphibians and reptiles; the islands (both Macaronesian and Mediterranean) host the highest richness of threatened species for all taxa occurs. Our results suggest that the main hotspots of biodiversity for terrestrial vertebrates may be extensively influenced by the climate change projected to occur over the coming decades, especially in the Mediterranean bioregion, posing serious concerns for biodiversity conservation.

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Podarcis tiliguerta is an insular Mediterranean lacertid lizard endemic to Corsica, Sardinia and many neighbouring small islands. The genetic structure and population heterogeneity of the species were studied by means of allozyme electrophoresis at 20 presumptive gene loci. The observed heterozygosity (H0) decreases southwards towards more arid climatic regimes. No severe reduction in genetic variability was found in samples from the tiny satellite islands, except for a population inhabiting a very small island off the south-western coast of Sardinia (Meli Island), in which about 80 per cent of the genetic variability was lost. Population heterogeneity analysis carried out by the estimation of Wright's F-statistics demonstrated substantial genetic differentiation among populations. The value of FST (0.460) exceeds values known for other lizard species. F-statistics and genetic distance data show that genetic variation is distributed into three geographically coherent population groups. The first group includes populations from the northern part of the range (Corsica), the second includes populations from the small islands off the south-eastern coast of Corsica (Cerbicale and Lavezzi), and the third comprises populations from the southern part of the range (Sardinia and Meli Island). The pattern of genetic variability and the apparent dma! variation of alleles at a few loci (Idh-1, Gapd, Gpi) indicate that the subdivided genetic structure of P tiliguerta is moulded by the interplay of stochastic processes and agents selectively affecting allele frequency changes.