Multiple Quaternary refugia in the eastern Guiana Shield revealed by comparative phylogeography of 12 frog species

The Guiana Shield is one of the most pristine regions of Amazonia and biologically one of the richest areas on Earth. How and when the massive diversity of life that exists in Amazonia arose remains the subject of considerable debate. The prevailing hypothesis of Quaternary glacial refugia suggests that a part of the eastern Guiana Shield, among other areas in Amazonia, served as stable, forested refugia during periods of aridity. However, the recently proposed Disturbance-Vicariance hypothesis proposes that fluctuations in temperature on orbital timescales, with some associated aridity, have driven Neotropical diversification. The expectations of the temporal and spatial organization of biodiversity differ between these two hypotheses. Here, we compare the genetic structure of 12 leaf-litter inhabiting frog species from the Guiana Shield lowlands using a combination of mitochondrial and nuclear sequence in an integrative analytical approach that includes phylogenetic reconstructions, m...