Stability Predicts Genetic Diversity in the Brazilian Atlantic Forest Hotspot

TLDR

Biodiversity hotspots are globally mapped but lack detailed distribution data, limiting conservation amid rapid environmental change. The study compares hypotheses of assemblage‑scale responses to late Quaternary climate change using frogs, ecological niche models, and Bayesian analyses of multispecies molecular data. The authors used frogs as indicators, built ecological niche models under paleoclimates, and performed simultaneous Bayesian analyses of multispecies molecular data. The analysis identifies a climatically unstable southern Atlantic forest that served as a refugium, revealing a hotspot within the Brazilian Atlantic forest and establishing a validated approach for biodiversity prediction and new conservation priorities.

Abstract

Biodiversity hotspots, representing regions with high species endemism and conservation threat, have been mapped globally. Yet, biodiversity distribution data from within hotspots are too sparse for effective conservation in the face of rapid environmental change. Using frogs as indicators, ecological niche models under paleoclimates, and simultaneous Bayesian analyses of multispecies molecular data, we compare alternative hypotheses of assemblage-scale response to late Quaternary climate change. This reveals a hotspot within the Brazilian Atlantic forest hotspot. We show that the southern Atlantic forest was climatically unstable relative to the central region, which served as a large climatic refugium for neotropical species in the late Pleistocene. This sets new priorities for conservation in Brazil and establishes a validated approach to biodiversity prediction in other understudied, species-rich regions.