Characterization and biogeographic history of neotropical dry ecosystems

Abstract The Neotropical region holds the largest species richness in the globe, occurring from Central Mexico to southern of Brazil. In this paper, we aim to summarize the main information available in the literature that characterizes the Neotropical biomes of Seasonally Dry Forests (SDF), Chaco and Savannas. Here we surveyed and reviewed biogeographic hypotheses concerning these environments that seek to explain their historical dynamics. Our goal is to offer a characterization of these biomes as a major step towards the understanding of the main hypotheses biogeographical associated with them. Although it supports an attractive scenario for research, Neotropical species are poorly studied, and questions concerning their ecological aspects, origin, evolutionary history and maintenance of the high biodiversity are unknown or even little understood. Although our review presents researches with different points of view regarding the biogeographic dynamics of vegetation formations, there is a consensus of being the product of a complex interaction between the historical, ecological and biological processes. Biodiversity studies of threatened regions, such as the Neotropic, are guidance for simulations and impacts predictions, for plans and research strategies.