Boxandwhisker plots of Ka/Ks ratio distributions for GCO and nGCO genes for various datasets used in this study. Significant differences in Ka/Ks ratios were observed between GCO and nGCO genes both in the overall dataset (Wilcoxon ranksum test: W = 203313, Pvalue = 0, standard deviations 0.09 and 0.18 respectively) and in the subset of duplicated genes (DGCO: Duplicated GCO genes, DnGCO: Duplicated nGCO genes. W = 13595.5, Pvalue = 0, standard deviations 0.13 and 0.17 respectively). The same coloring scheme with Fig. 1A. is used for easy comparison.