A large historical refugium explains spatial patterns of genetic diversity in a Neotropical savanna tree species.

Background And Aims: The relative role of Pleistocene climate changes in driving the geographic distribution and genetic diversity of South American species is not well known, especially from open biomes such as the Cerrado, the most diverse tropical savanna, encompassing high levels of endemism. Here the effects of Quaternary climatic changes on demographic history, distribution dynamics and genetic diversity of Dimorphandra mollis, an endemic tree species widely distributed in the Cerrado, were investigated.

Methods: A total of 38 populations covering most of the distribution of D.