The history of Seasonally Dry Tropical Forests in eastern South America: inferences from the genetic structure of the tree Astronium urundeuva (Anacardiaceae)

• DOI: 10.1111/j.1365-294x.2008.03817.x
• Publication Date: 2008-06-03T13:23:45Z
• Authors: S. CAETANO; D. PRADO; R. T. PENNINGTON; S. BECK; A. OLIVEIRA‐FILHO; R. SPICHIGER; Y. NACIRI
• Keywords: Vicariance; Anacardiaceae; Isolation by distance

Today, the Seasonally Dry Tropical Forests (SDTF) of eastern South America occur as large, well-defined nuclei (e.g. Caatinga in northeast) and smaller enclaves within other vegetations Cerrado Chaco). In order to infer way present SDTF distribution was attained, genetic structure Astronium urundeuva, a tree confined SDTF, assessed using two chloroplast spacers nine microsatellite loci. Five haplotypes were identified, whose spatially structured. The most common divergent suggested former vicariance progressive divergence due isolation. More recent range expansions these lineages subsequently occurred, leading secondary contact at southern limit nucleus. multilocus-Bayesian approach microsatellites consistently identified three groups populations (Northeast, Central Southwest). Isolation by distance found Northeast Southwest whereas admixture detected group, located transition between domains. All together, results support existence group. This study provides arguments that favour previously more continuous formation America.