Le jeudi 19 septembre 2014 à 13h00, en salle de conférences de l'OSUR, campus de Beaulieu, bât.
Le jeudi 19 septembre 2014 à 13h00
, en salle de conférences de l'OSUR, campus de Beaulieu, bât. 14b, UR1“Gene sorting”: The thin line between species sorting and parallel adaptive radiationRésumé :
When environmental gradients are spatially repeated, occupation of habitats may occur through dispersal of species or, alternatively, by repeated in situ adaptation. Recent genomic tools allow us to get insight into the genetic basis of these adaptations. Work on spider and carabid radiations from the Galapagos, and recurrent adaptation to tidal habitats of a salt marsh beetle shows that such repeated adaptation often involves exactly the same allelic variants. The fixation of similar alleles in similar habitats may either be the result of introgression of adaptive alleles between populations, or even through dispersal of ecotypes followed by in situ neutral gene exchange between ecotypes. This renders the distinction between species dispersal and repeated adaptive radiation often less clear cut as generally assumed. I will further demonstrate how non-genetic mechanisms may facilitate the occupation of new niches. Besides this work, I also have a great interest in the evolutionary stability of alternative strategies, such as dispersal and intrasexual dimorphisms.Contact : Frederik HENDRICKX