Regional tectonics shaped plant biodiversity in Colombian Andes

Northern South America, particularly the geologically dynamic Colombian Andes, stands as a region of highest plant biodiversity. While the influence of mountain uplift in the tropical Andes on biodiversity patterns is well-recognized, the repercussions of these landscape changes on the evolutionary dynamics of the local flora have been understudied. Here, we aim to fill this gap by investigating the role of uplift history and landscape evolution in driving the assembly and maintenance of plant biodiversity in the Colombian Andes. We integrate a comprehensive reconstruction of individual geological blocks with plant phylogenies, distribution patterns, and the resulting biogeographic structuring of the endemic flora. Our comparative analysis reveals a substantial agreement between the geological blocks and biogeographic realms instead of climate, indicating the fundamental role of regional tectonics shapes the observed pattern of biodiversity. Notably, the northern segments of the Western and Central Cordillera and Eastern Cordillera, representing the two most-recent fast uplift blocks, exhibit a higher prevalence of endemic species and a significant accumulation of in situ speciation events over the last 10 million years. Our findings provide a detailed perspective on how landscape changes have driven the diversification of flora in the Colombian Andes and contribute to a broader understanding of the intricate interplay between geological processes and plant evolution, emphasizing the importance of considering regional tectonic dynamics in unraveling the heterogeneous biodiversity patterns on Earth.