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Mountains are renowned for their bountiful biodiversity. Explanations on the origin of such abundant life are usually regarded to their orogenic history. However, ancient mountain systems with geological stability also exhibit astounding levels of number of species and endemism, as illustrated by the Brazilian Quartzitic Mountains (BQM) in Eastern South America. Thus, cycles of climatic changes over the last couple million years are usually assumed to play an important role in the origin of mountainous biota. These climatic oscillations potentially isolated and reconnected adjacent populations, a phenomenon known as flickering connectivity, accelerating speciation events due to range fragmentation, dispersion, secondary contact, and hybridization. To evaluate the role of the climatic fluctuations on the diversification of the BQM biota, we estimated the ancient demography of distinct endemic species of animals and plants using hierarchical approximate Bayesian computation analysis and Ecological Niche Modelling. Additionally, we evaluated if climatic oscillations have driven a genetic spatial congruence in the genetic structure of codistributed species from the Espinhaço Range, one of the main BQM areas. Our results show that the majority of plant lineages underwent a synchronous expansion over the Last Glacial Maximum (LGM, c. 21 thousand years ago), although we could not obtain a clear demographic pattern for the animal lineages. We also obtained a signal of a congruent phylogeographic break between lineages endemic to the Espinhaço Range, suggesting how ancient climatic oscillations might have driven the evolutionary history of the Espinhaço's biota.

Aechmea distichantha Lem. is a Bromeliaceae species with wide geographic distribution; it is found in Atlantic Forest, "Cerrado" and "Chaco" ecoregions from Tropical to Subtropical areas in Brazil, Bolivia, Paraguay and Argentina. The species has a great ornamental value and is currently threatened by its predatory exploration and by habitat loss. The lack of suitable molecular markers hampers research on its genetic diversity, which could contribute to the design of conservation plans and to demographic and phylogeographic studies of the species. Here, we tested the cross-amplification of 43 nuclear microsatellite markers, originally developed for other bromeliad species. We obtained high cross-amplification indices (37 SSR primers, 86%) and polymorphism (17 SSR primers, 46%). We then used ten SSR loci to genotype individuals from three populations of A. distichantha. The observed and expected heterozygosity per locus in the A. distichantha populations ranged from 0.182 to 0.735 and 0.297 to 0.830, respectively. These loci showed sufficient variability to be used in future the studies of genetic diversity, genetic structure and phylogeography of A. distichantha to understand its evolutionary history during its dispersal, colonization and adaptation to different ecoregions.