Comparative transcriptomics of Oophaga Poison Frogs
Aposematism and crypsis are two contrasting anti-predator strategies. Aposematic animals often possess a conspicuous warning coloration to signal their predators harmful phenotypes (chemical defences, spines, etc.), while cryptic animals are camouflaged and generally non-harmful. In Neotropical poison frogs (Dendrobatidae) many species are colour polypytic, with populations showing different colour morphs which vary in conspicuousness. In the well-studied strawberry poison frog O. pumilio the more conspicuous colour morphs are more toxic, thus presenting an aposematic phenotype while more cryptic colour morphs are less toxic. In our previous studies, we found that the expression of genes involved in pigment production and structural coloration differs between colour morphs in O. pumilio. Here we extend on these findings by investigating the genomic link between coloration and toxicity in detail. We will characterize the alkaloids and pigments as well as underlying expression and genetic variation of coloration- and alkaloid-related genes in three Oophaga species. The central question of this project is whether genotype and phenotype are similarly correlated between the red and green colour morphs in the three Oophaga species thus providing evidences on whether the evolutionary trajectories of aposematic traits resulted from deterministic and predictable or idiosyncratic and unpredictable evolution.