Niche-dependent forest and savanna fragmentation in Tropical South America during the Last Glacial Maximum

This paper investigates the extent of Amazonian forest and savanna fragmentation during the Last Glacial Maximum (LGM), challenging the long-standing refugia hypothesis. By bias-correcting vegetation distributions from a Dynamic Vegetation Model (DVM) with paleoclimate simulations, the study reveals fragmented forests with extensive humid forests to the west and forest islands in central/southern Amazonia. Drier ecosystems may have merged into continuous savanna, but reconstructions suggest taller, dense woodland/tropical savanna vegetation connecting disparate forest fragments. This ecotonal biome may have acted as a corridor for generalist species, while simultaneously serving as a barrier for specialists, potentially driving diversification.

Douglas I. Kelley, Hiromitsu Sato, Michaela Ecker, Chantelle A. Burton, João M. G. Capurucho, John Bates