Grözinger, F., H. Feldhaar, J. Thein & M.-O. Rödel

Testing the impact of environmental conditions and matriline on tadpole developmental traits in the European Common Frog, Rana temporaria, in the field. pp. 201-209 plus Supplementary Material.

Abstract. Phenotypic trait variation among populations is frequently studied to explore evolutionary mechanisms of adaptation processes. However, most studies are conducted over large spatial scales making gene flow between organisms unlikely. Here we explored differentiation of developmental traits among individuals within a small spatial area and asked if differences were environmentally induced and / or had a genetic basis. In a common garden approach we compared the development of Rana temporaria tadpoles, developing either in ponds where the clutch had been originally deposited or in alternative ponds. Forest ponds were small to medium sized, geographically close, and all used as breeding sites by the species. Our main findings were: The variation among pond characteristics was sufficient to generate differences in larval developmental traits among ponds. Non-sibling tadpoles developing in a common environment differed in developmental traits. Sibling tadpoles developing under different conditions showed differences in developmental traits. Tadpoles developing in their native environment did not always perform better than ‘foreign’ tadpoles. These results indicate that environmental conditions shape developmental plasticity to some extend (siblings raised under different conditions differed) but that matriline x environment interactions likewise influence the plasticity of developmental traits (non-siblings differed in their reactions within a common environment).

Key words. Amphibia, Anura, matriline x environment interaction, phenotypic divergence, within-population variation.