Fig 5. Alternative accessible evolutionary paths.

(A) The fitness of beneficial mutations found (F) in Evolve and Resequence studies is significantly higher than the fitness of beneficial mutations not found (NF) in sulfate-limitation but not in glucose-limitation. The significance of the difference between the two boxplots for each condition was estimated using a Wilcoxon-ranked test. (B) Each point represents the fitness of a strain and the proportion of Evolve and Resequence samples with the corresponding gene mutated. SUL1 dominates the fitness and mutational spectrum. Several mutations have a high fitness but have never been detected in Evolve and Resequence studies and might correspond to potential drivers of adaptation.