Date(s) - 16/12/2015
11 h 00 min - 12 h 00 min
Catégories Pas de Catégories
Every evolutionary biologist will say that Convergent evolution is an important phenomenon of the organic evolution( Conway Morris 2003 , McGee 2011, Losos 2011 , Gordon et al 2015 ). However this concept is fuzzy as convergent evolution have several meaning in the literature , this has been described in part by Tristan Stayton (2015). The goal of this presentation is 1) to show that these cases of “repetitive similarities” should be defined in a better way and 2) to present a road map to study these phenomenons once they are better defined.
Lot of tries have been done to better describe convergent evolution since the 20th century, This was done mainly by separating the concept in two sub concepts , parallel and convergent evolution but these add more confusions (Arendt and Reznick 2008) . From ours point of view the confusion came from the fact that most of the authors gave sub definitions based on the genetic mechanisms involved in the evolution of the convergent evolving character. We first propose to make the distinction between convergence at the level of species and the level of characters . We there propose two neologisms that can be apply to all the biological levels: isoconvergent and alloconvergent evolution : iso from the same ancestral state allo from a different ancestral state . This distinction is important as in the case iso convergent evolution , one can suspect that the underlying molecular mechanism could be similar(Stern and Orgozozo 2008) .Such cases could be used as meta-model (Kopp 2009), that in turn can be used to decipher biological mechanisms at genetic, epigenetic, transcriptional and other biological levels. We further propose 1) to re analyse all the case of convergent evolution at phenotype level described in the literature and sort out the case of isoconvergences,2) to identify undescribed cases of iso convergent evolution and 3) a road map to study these cases at the different biological level and 4) the development of a data base. The usefulness of the analyse of the case of alloconvergent evolution will be also discussed
I will present , in this epistemological contexts , the first cases studied in the lab: the b lacatamase as weel as or project on the evolution of complex viviparity