Genomic evidence for the parallel evolution of coastal forms in the Senecio lautus complex. Issue 11 (25th May 2013)

• Record Type: Journal Article
• Authors: Roda, Federico; Ambrose, Luke; Walter, Gregory M.; Liu, Huanle L.; Schaul, Andrea; Lowe, Andrew; Pelser, Pieter B.; Prentis, Peter; Rieseberg, Loren H.; Ortiz‐Barrientos, Daniel
• Is Part Of: Molecular ecology. Volume 22:Issue 11(2013)
• Page Start: 2941
• Page End: 2952
• Publication Date: 2013-05-25
• Subjects: Molecular ecology -- Periodicals; Molecular population biology -- Periodicals; 576
• DOI: 10.1111/mec.12311
• Languages: English
• ISSNs: 0962-1083

Abstract

<abstract abstract-type="main" id="mec12311-abs-0001"> <title>Abstract</title> <p>Instances of parallel ecotypic divergence where adaptation to similar conditions repeatedly cause similar phenotypic changes in closely related organisms are useful for studying the role of ecological selection in speciation. Here we used a combination of traditional and next generation genotyping techniques to test for the parallel divergence of plants from the <italic>Senecio lautus</italic> complex, a phenotypically variable groundsel that has adapted to disparate environments in the South Pacific. Phylogenetic analysis of a broad selection of <italic>Senecio</italic> species showed that members of the <italic>S. lautus</italic> complex form a distinct lineage that has diversified recently in Australasia. An inspection of thousands of polymorphisms in the genome of 27 natural populations from the <italic>S. lautus</italic> complex in Australia revealed a signal of strong genetic structure independent of habitat and phenotype. Additionally, genetic differentiation between populations was correlated with the geographical distance separating them, and the genetic diversity of populations strongly depended on geographical location. Importantly, coastal forms appeared in several independent phylogenetic clades, a pattern that is consistent with the parallel evolution of these forms. Analyses of the patterns of genomic differentiation between populations further revealed that adjacent populations displayed greater genomic heterogeneity than allopatric populations and are differentiated according to variation in soil composition. These results are consistent with a process of parallel ecotypic divergence in face of gene flow.</p> </abstract>