Figure 2. The number of migrations of the genus Neophocaena along the western Pacific over time.

The migration rates are indicated by the parameter M multiplied by 1,000. The time scale is shown in mutational units by generation. A box indicates a time interval covering the strengthening migration during 0.00815–0.00995 along the marine coast, which is separately translated into absolute time using substitution rates of 0.6%, 0.98% and 1.2% per million years at the bottom.