Fig. 2

Evolutionary trajectories of the most prominent clusters of mutations. Mutations arose either in the MATa (left) or MATα (right) pools. On the vertical axis are the names of the mutations, giving the closest gene, coordinates relative to that gene, and the nature of the nucleotide substitution. On the horizontal axis are each of the six evolutionary timepoints (UV, R1, R2, R3, R4, R5), and the mean allele frequency change (M). Frequency of the mutant alleles is represented by shades of green. Mean allele frequency changes are represented in shades of red (M < 1, declining frequency) to blue (M > 1, increasing frequency). Hierarchical clustering of individual evolutionary trajectories is represented by dendrograms on the left. Mutations were assigned to cohorts of mutations (a1-5, α1-3) on the basis of this clustering. Mutations present in highly tolerant mutant R57 are highlighted in bold. The large and low frequency cohort a2 is omitted from the figure for clarity and brevity. See Additional file 3: Figure S1 for full dataset