A case of reproductive character displacement in female palmate newts (Lissotriton helveticus).

Reproductive character displacement is commonly described as larger phenotypic differences between species living in sympatry rather than in allopatry. We investigated this phenomenon on two amphibians found in their contact zone where syntopic and allotopic sites alternate. To test the effect of syntopy with Lissotriton vulgaris on the Lissotriton helveticus phenotype, we studied the morphology of adult males and females while controlling for environmental factors (i.