The Role of Historical Barriers in the Diversification Processes in Open Vegetation Formations during the Miocene/Pliocene Using an Ancient Rodent Lineage as a Model

• DOI: 10.1371/journal.pone.0061924
• Publication Date: 2013-04-18T21:11:31Z
• Authors: Fabrícia F. Nasci...; Ana Lazar; Albert N. Menezes; Andressa da Matta...; Jânio C. Moreira; Jorge Salazar-Bravo; Paulo S. D′Andrea; Cibele R. Bonvicino
• Keywords: Lineage (genetic); Paraphyly; Endemism; Genetic algorithm

The Neotropics harbors a high diversity of species and several hypotheses have been proposed to account for this pattern. However, while forested domains are frequently studied, less is known from open vegetation formations occupying, altogether, larger area than the Amazon Forest. Here we evaluate role historical barriers riverine hypothesis in speciation patterns small mammals by analyzing an ancient rodent lineage (Thrichomys, Hystricomorpha). Phylogenetic biogeographic analyses were carried out with mitochondrial nuclear DNA markers analyze evolutionary relationships between Thrichomys lineages occurring dry along both banks Rio São Francisco. This river one longest South America whose course water flow modified inland tectonic activities climate changes. Molecular data showed higher number previously described. T. inermis complex 2n = 26, FN 48 was observed showing paraphyletic arrangement, suggesting that crossing had occurred, east west. A similar pattern also apereoides complex. occurred Late Miocene when followed different course. current geographic distribution their phylogenetic suggested existence frequent past connections middle section extensive palaeodune region found has identified as centre endemism vertebrate likely be center diversification.