Abstract
Pleistocene climatic changes have played a major role in the evolution of Brazilian Atlantic Forest and South America biodiversity but their impacts on the genetic structure of widely distributed species remain unclear. Here, we investigate mitochondrial DNA (mtDNA) diversity in 21 geographical populations of Drosophila sturtevanti, Nucleotide sequences of the cytochrome C oxidase subunits I and II genes (COI and COII, respectively) from 163 individuals, showed a significant north-south structure, in spite of an overall low level of variation. The haplotypes clustered in three groups that showed strong correlations with geographical and climatic variables, suggesting that local adaptations might have contributed to differentiation within the species. Coalescent-based analyses indicated that the three clusters have differentiated nearly ∼17.000 years ago, suggesting a major role for Pleistocene changes in shaping current day distributions and differentiation of widespread Neotropical species.
Acknowledgments
We thank Prof. Dr. Daniela de Toni, Prof. Dr. Claudia Rohde and Prof. Dr. Hermes J. Schmitz for supplying some strains of D. sturtevanti, FAPESP for support of this project (process number 2014/14059-0, 2016/11994-5), CAPES for supporting the Postgraduate Program in Biosciences of Unesp/Ibilce and CAPES for the doctoral and PDSE scholarship granted to Samara Videira Zorzato (PDSE/CAPES – Proc. 88881.190070/2018-01).
Disclosure statement
No potential conflict of interest was reported by the author(s).