Figure 2.

Maximum clade credibility tree with time estimates for colonization events and basal diversifications within red fox mtDNA control region lineages. For the dating of phylogeographic events we used a combined approach, utilizing tip dates based on published ancient DNA red fox sequences [25], plus the arctic fox as exterior calibration point. This tree shows the results for a root height prior of 1.75-4 million years (My), according to the 95% credibility interval in Perini et al. [80] for the divergence time between red and arctic fox (Table  2). White: Nearctic lineage haplotypes; grey: Japanese haplotypes (lineages Honshu/Kyushu and Hokkaido II); black: Holarctic lineage haplotypes, including Japanese lineages Hokkaido Ia and Ib; ka: thousand years. Nodes marked with an asterisk were supported by posterior probability values >0.95. Samples used for tip calibration are marked with a ♦ symbol. Median ages and 95% highest posterior density ranges in brackets show the estimated ages of major lineages, and of the most basal nodes within these lineages. Our discussion focuses on lineages/nodes with ≥0.95 statistical support, recognizing that longer mtDNA sequences will be required to resolve larger proportions of the red fox mitochondrial phylogeny (see [58-62]).