3.3.5 Mitochondrial Network Analysis
The median joining network analysis using mitochondrial genomes and a larger sampling of historical whales produced similar results to the nuclear sequences in showing an absence of clustering of haplogroups based on the NA geographic origin of the samples (Fig. 3). Additionally, there appears to be continuity through time as haplogroups are shared between two of the four present-day NWA samples with whales killed in the same waters over a century ago. The Antarctic and South Atlantic whales cluster within the NA blue whales closest to the NWA blue whale NW-M6. Global geographic structuring using a larger sampling of whales (154) but a smaller amount of sequence (mitochondrial control region) was weak or nonexistent (Fig. S1).