Adaptations of some amphibian species to Mediterranean environmental conditions

Recent morphological and electrophoretic studies on the amphibian species Rana ridibunda, Bufo viridis, Hyla arborea and Triturus alpestris from northern and central Greece revealed a high degree of morphological and genetic variation. Morphological variation was assessed by colour patterns and several morphometric characters. Genetic variation was estimated from values of the parameters P (proportion of polymorphic loci) and H (mean heterozygosity), 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. viridis and H. arborea revealed some differences concerning their reproductive patterns. The results of our studies provide evidence that the morphological and genetic variability as well as the differentiation of reproductive patterns are partly adaptations to the ecological factors of the area.