Plant Microevolutionary Processes in the Campos Sulinos: Why Do They Matter?

The Campos Sulinos are a complex of grassland ecosystems occurring in Brazilian territory that belong to two phytogeographical domains, the Brazilian Atlantic Forest and the Pampa. Floristic and phylogenetic analyses have pointed to the division of the region based on ecological divergence. Thus, it is crucial to understand the processes driving plant diversity within each region. Here, we discuss the microevolutionary processes in plants from the Campos Sulinos, mainly using plant genera that originated and diversified in the region. As the Pampa ecoregion extends to Uruguay and Argentina, some examples were included with distribution beyond the Campos Sulinos. We also explored some perspectives to employ population genetics data in conservation efforts. The current species distribution and intraspecific diversity result from an intricate and complex net between historical and contemporary processes and species-specific characteristics. Although the influence of past climate changes on the habitat distribution is associated with the diversification patterns in plant species from the Campos Sulinos, the rapid changes coupled with the habitat loss due to land use can threaten the persistence and evolution of species. Finally, we argued that, whenever possible, the management in the Anthropocene should include the conservation of population genetic diversity.