Figure 4

The purple line indicates the mean pairwise divergence of the Ka/Ks ratio for 13 PCGs among 16 Neritimorpha mitochondrial genomes. The 16 species of Neritimorpha are listed in Table 1. The pink and blue boxes indicate the number of nonsynonymous substitutions per nonsynonymous site (Ka) and the number of synonymous substitutions per synonymous site (Ks), respectively.