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Séminaires MSC
"Matière et Systèmes Complexes"

                      

Lundi 2 avril 2007 à 11h30
Bâtiment Condorcet, 4ème étage, salle 454 A.

Carole Knibbe
(Hôpital Necker, Paris)


Lessons from the evolution of artificial genomes

In this talk, I will discuss the evolution of gene number and the evolution of the amount of non-coding DNA in the artificial organisms of the "aevol" platform. These organisms were designed with three organisation levels (genome, proteome, phenotype) and are submitted to local mutations as well as large rearrangements of the genomic structure. Experiments with various per-locus mutation rates show that the genome size always stabilises, although the fitness computation does not penalise genome length. Both the gene number and the amount of non-coding DNA are closely dependent on the mutational pressure, resulting in a constant genome-wide variability level. Thus the
evolution of genome structure reflects a balance between several conflicting pressures: (i) evolving more and more complex functions with more and more genes, (ii) preserving the mutational robustness by keeping the genome small and (iii) preserving  genome evolvability by keeping some non-coding DNA.