Animal coloration plays a critical role in ecological interactions and physiological processes. Aposematism and crypsis are two contrasting antipredator strategies that involve a wide color palette, yet the molecular basis driving such color diversity is understudied. The granular poison frog, Oophaga granulifera, displays a diverse range of colors, including both aposematic red and cryptic green morphs, making it an ideal model to study color polymorphism. This study focuses on the population genetics and selection signatures in aposematic and cryptic populations of O. granulifera, by integrating genomic and transcriptomic tools.