Figure 2

Substitution rates in paralogs and their sister singletons. A: Scatterplot of K_a (log scale) in paralogous vs. their nearest sister outgroup orthologous singleton clades. Colours of circles and lines indicate three classes of clade age measured in K_s units estimated for the speciation event. Inset: Frequency of triplets in which paralogs evolve faster (K_{a, para} > K_{a, single}) than singletons (above 0 line) and vice versa (below 0 line). Filled portions of bars represent the frequency of triplets in which this difference is significant after Bonferroni adjustment (P_B < 0.05). B-D: Distribution of substitution rates (relK_a), normalized by the upper bound estimate of duplication age (B), absolute difference in polarity (|dPolarity|, C) and exchangeability (D) in paralogous (red) and singleton (blue) clades.