Figure 5.

Molecular phylogeny and pattern of nucleotide substitutions of the S5a-derived region of PIPSL from all hominoid lineages [61]. The branches are drawn in proportion to the number of substitutions, with nonsynonymous (n) and synonymous (s) substitutions shown above each branch (n : s). An ancestral PIPSL lineage (indicated by bold lines) gradually accumulated 19 nonsynonymous and 2 synonymous substitutions. Since the split from the ancestral lineage, all the respective lineages have accumulated synonymous substitutions, except for gibbons, which still have a high n : s ratio (17 : 2).