Intestinal, Body and Tail Plasticity in Rhinella schneideri (Bufonidae) Tadpoles Induced by a Predator Insect (Belostoma elegans)

Abstract

According to the adaptive plasticity hypothesis, predator-induced traits in potential prey animals are expected to have costs for those organisms in predatorfree environments. In this study, we analysed if the intestinal length, tail length and body length changes in Rhinella schneideri tadpoles when the tadpoles were exposed to caged predators (Belostoma elegans). We used a randomized block design with a factorial combination of one density of tadpoles and four densities of caged predators. The predators had a significant impact on gut length and tail length but not on body length. We found that tadpoles reared with no predators had relatively longer guts than those reared with caged predators. The reduction in gut length appears to interplay between behaviour, life history, morphology and physiology.