Le Genoscope-CEA vous propose un séminaire qui se tiendra jeudi 9 novembre, à 11h en salle Jacob (Bât.G1 - RDC)
Jesus Mavarez, Chargé de recherche au Laboratoire d’Écologie Alpine (CNRS/ Université Joseph Fourier) à Grenoble
Evolution in the fastest evolving place on Earth : The explosive diversification of Espeletia (Asteraceae) in the high-elevations of the Northern Andes.
invité par Adriana Alberti
Lineages or habitats that exhibit rapid rates of diversification represent unique opportunities to understand the ecological and evolutionary mechanisms that drive the process of speciation. It has been proposed recently that the Northern Andes high-elevation ecosystem known as paramo harbours such a concentration of lineages with rapid rates of diversification that it should be considered as ‘the fastest-evolving place on Earth”. Here we review the available evidence supporting this claim and provide a preliminary analysis of the diversification of the giant rosette plants in the genus Espeletia (Asteraceae) using whole chloroplast genomes and about a million bases of nuclear genetic data gathered from whole genome shotguns. We show that the 140 species in the group evolved from a common ancestor living 2.3 Mya, resulting in exceedingly high diversification rate ranked indeed amongst the fastest measured in a plant group. Morphological evolution in Espeletia has been rapid as well, apparently in association with climatic (glacial) cycles during the Pleistocene. Further genomic studies will however be necessary in order to understand whether these phenomena are widespread amongst paramo taxa, and a few ideas in that regards will be presented during this talk.