La Harpe et al. 2015 (Conference Paper) Tillandsioids

Genomics of speciation and species cohesion among Tillandsioids in Neotropical mountains

Author(s):—M.de La Harpe, M. Paris, O. Loiseau, I. Olivares, A. Weigand, W. Till, J. Grant, T. Kromer, L. Versieux, G. Martinelli, M. Kessler, N. Salamin & C. Lexer in Benko-Iseppon, A.M.; Alves, M. & Louzada, R. (2015) An overview and abstracts of the First World Congress on Bromeliaceae Evolution. Rodriguésia 66(2): A1-A66.

Publication:— (2015).

Abstract:—The adaptive radiation of bromeliads is one of the most diverse and enigmatic of the Neotropics. The Tillandsioideaesubfamily represents a pertinent system for studying adaptation, speciation, and clade diversification in Neotropicalplants. Our main research aim is to unravel the drivers and limits of diversification at micro-evolutionary timescales, i.e. at the level of diverging populations, species, and species complexes. Tillandsioid taxa were sampledalong elevation gradients of various Central and South American mountain regions, including Mexico, Ecuadorand Brazil. Common species (geographic replicates) and local endemics were defined based on their natural distribution ranges and ecological preferences. Geographic replicates were chosen preferentially to disentangle thelikely evolutionary mechanisms responsible for speciation and species cohesion. A genomic approach, combiningRNA-sequencing and restriction site Associated DNA sequencing (RAD-seq), will generate genetic data for bothneutral and non-neutral regions of the genomes of these taxa. The genomic information yielded by this approach willbe employed to characterize gene flow and allelic diversity within and among parapatric tillandsioid populationsand species along elevation gradients. Great emphasis will also be given to analyses of population divergenceto shed light on the genetic mechanisms of speciation and species persistence. Finally, parallel genotypic andphylogenetic patterns of evolution will be evaluated jointly and ecological correlates of population and speciesdivergence will be identified to provide a better understanding of the diversification process. Current results andkey points from this research will be presented, including spatial distributions of the sampled taxa, proof-ofconcept data from RAD-seq, and available experimental/sampling designs towards reaching our research goals.

Keywords:—Clade Diversification; Population Genetics; Tillandsioideae.