Historical biogeography of the Brazilian Atlantic forest and the Carnaval–Moritz model of Pleistocene refugia: what do phylogeographical studies tell us?

The present study uses published phylogeographical studies to test the Carnaval–Moritz (CM) model of forest dynamics in the Atlantic forest of Brazil. The model predicts that a large forested area in the north–central region of this biome has remained stable during the last glacial maximum, and only relicts in its current southernmost distributions. All available sequences for phylogeographical studies on vertebrates on the Atlantic forest were obtained from GenBank. All datasets consisted of mitochondrial sequences and were submitted to the same analyses, including time of divergence and migration rates between phylogeographical lineages, as well as historical demography analyses, including neutrality tests and Ne estimates. The species studied showed different degrees of phylogeographical structure. Two contact zones are defined: one very heterogeneous in south‐east Brazil that was largely congruent with the CM model and one around the Doce river further north. Population genetics analyses showed a smaller effective number on southern population, and most of these southern populations showed evidence for recent demographic expansion. These features are also in agreement with the CM model. Additionally, divergence/expansion events dated back to the Pleistocene epoch in all but one organism. According to hierarchical approximate Bayesian computation analysis, most of the data can be attributed to a single event. The results highlight the need for more finescale studies in the Atlantic forest. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 499–509.