Myr), based on the value estimated in the aDNA analysis. The modern and ancient DNA data sets were obtained from different stocks (Bering-Chukchi-Beaufort Seas and Spitsbergen, respective- ly), but there appears to be little molecular or morphological evidence for the discreteness of any of the five designated stocks of bowhead whales [73,75,76]. To estimate the average substitution rate across balaenids, control region sequences were obtained from GenBank for the three extant species of right whale (Eubalaena japonica, E. australis, and E. glacialis). These were aligned with the corresponding sequence from Balaena mysticetus haplotype A. The alignment was analysed with BEAST using fossil calibrations. The oldest fossil representative of either the Eubalaena or Balaena lineage dates from the Pliocene (1.8–5.3 Myr BP) [77]. Rooney et al. [9] summarised this information by taking a mean value of 3.4 Myr, which we have adopted for comparative purposes. 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