Adaptations of some amphibian species to Mediterranean environmental conditions

Recent morphological and electrophoretic studies on the amphibian species R ana ridibunda, Bufo viridis, Hyla arborea and Triturus alpestris from north ern and central Greece revealed a high degree of morphological and genetic variation. Morphological variation was assessed by colour patterns and seve ral morphometric characters. Genetic variation was estimated from values of the parameters P (proportion of polymorphic loci) and H (mean heterozygosi ty), which were found to increase in the order: Triturus alpestris (H 0.122 ) < Hyla arborea (H = 0.136) < Bufo viridis (H = 0.139) < Rana ridibunda (H = 0.149). Furthermore, our studies on the reproductive biology of R. ridibunda, B. vi ridis and H. arborea revealed some differences concerning their reproductiv e patterns. The results of our studies provide evidence that the morphological and gene tic variability as well as the differentiation of reproductive patterns are partly adaptations to the ecological factors of the area.