The Atlantic Forest is separated from the Andean tropical forest by dry and open vegetation biomes (Chaco and Cerrado). Despite this isolation, both rainforests share closely related lineages, which suggest a past connection. This connection could have been important for forest taxa evolution. In this study, we used the Saffron-billed Sparrow (Arremon flavirostris) as a model to evaluate whether the Andean and the Atlantic forests act as a refugia system, as well as to test for a history of biogeographic connection between them. In addition, we evaluated the molecular systematic of intraspecific lineages of the studied species. We modeled the current and past distribution of A. flavirostris, performed phylogeographic analyses based on mitochondrial and nuclear genes, and used Approximate Bayesian Computation (ABC) analyses to test for biogeographic scenarios. The major phylogeographic disjunction within A. flavirostris was found between the Andean and the Atlantic forests, with a divergence that occurred during the Mid-Pleistocene. Our paleodistribution models indicated a connection between these forest domains in different periods and through both the Chaco and Cerrado. Additionally, the phylogeographic and ABC analyses supported that the Cerrado was the main route of connection between these rainforests, but without giving decisive evidence against a Chaco connection. Our study with A. flavirostris suggest that the biodiversity of the Andean and of the Atlantic forests could have been impacted (and perhaps enriched?) by cycles of connections through the Cerrado and Chaco. This recurrent cycle of connection between the Andean and the Atlantic Forest could have been important for the evolution of Neotropical forest taxa. In addition, we discussed taxonomic implications of the results and proposed to split the studied taxon into two full species.
Bibliographical noteFunding Information:
We thank the collectors and staff of the institutions that loaned tissue samples used in this study: Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Instituto de Investigación de Recursos Biológicos Alexander von Humboldt; Museu Paraense Emílio Goeldi and Museo de Zoología of the Universidade Federal de Minas Gerais (UFMG). We thank the following institutions for granting collection permits: Administración de Parques Nacionales (Argentina), Ministerio de Ecología de Misiones, and environmental authorities of Bolivia and Brazil. We are also grateful to the Associate Editor Scott Edwards, to two anonymous referees because their comments helped to improve an early version of the manuscript, to Manolo Peres for helps with the ABC analyses, and to Dan Zornizer for the English language collaboration. This study was funded by: the Consejo Nacional de Investigaciones Científicas y Tecnológicas from Argentina (PIP 276, Proyecto Coop. Internacional CNPq-CONICET and CAPES-CONICET, as well as Proyecto Fondo IBOL), the Agencia Nacional de Promoción Científica y Tecnológica from Argentina (PICT 2012 1924 and PICT 2014 2154), and Fundação de Amparo à Pesquisa do Estado de São Paulo (BIOTA, 2013/50297-0) from Brazil, and National Science Foundation (DOB 1343578) and NASA from the USA. This work was partially developed in the Research Center on Biodiversity and Computing (BioComp) of the Universidade de São Paulo (USP), supported by the USP Provost's Office for Research.
© 2017 Elsevier Inc.
- Andean forest
- Approximate Bayesian Computation
- Atlantic forest
- Gallery forests