Integrating Genomic Tools to Predict Climate Adaptation and Vulnerability across a Latitudinal Gradient in a Brazilian Atlantic Forest Treefrog (Dendropsophus elegans)

Understanding how species will respond to rapid environmental change is a central question in conservation biology. Genome–environment association (GEA) and genomic offset analyses offer valuable tools for detecting local adaptation and assessing vulnerability to climate change. In this study, we investigate local adaptation signals and the adaptive potential to changing climates in Dendropsophus elegans, a widespread treefrog endemic to the Brazilian Atlantic Forest (AF), one of the world’s most threatened biodiversity hotspots. Using RAD-sequencing data from 29 individuals across 25 localities and a reference genome from D. ebraccatus, we identified 3,447 high-quality SNPs. We employed two GEA analyses to detect loci potentially under climatic selection across environmental gradients and estimate genetic offset related to climate change. Our analyses showed evidence of stronger genetic structuring in the northern and southern portions of the forest, and greater admixture in the central zone. Different GEA methods revealed 12 candidate loci linked to temperature seasonality and precipitation extremes suggesting populations adapted to local climatic conditions along the AF’s latitudinal gradient. Our findings suggest a potential adaptive divergence in D. elegans shaped by local climates. Under this assumption, and by quantifying genomic offset, we identified populations potentially at higher risk of maladaptation under future climate scenarios on the edges of the AF biome, particularly in the southwestern and coastal regions. These results underscore the importance of integrating adaptive genetic variation into conservation planning, particularly in rapidly changing and fragmented landscapes such as the Atlantic Forest.