The balaenid whale, comprising three species of right whales and the
bowhead whale, represents an ancient and highly endangered lineage of
marine mammals. To unravel the evolutionary history of balaenid whales
with respect to gene flow, a comprehensive analysis based on
whole-genome data was conducted for all species within this group.
Employing population genomic methodologies, we revealed the polytomic
nature of extant right whales, identified passage of historical
trans-equatorial migration, and provided estimates to the age of the
group. Furthermore, we investigated the impact of glacial cycles on the
connectivity of bowhead whale populations. By employing multiple
complementary approaches to detect gene flow, we identified and
characterized gene flow events from bowhead whales to North Atlantic
right whales, offering detailed insights into the process. Lastly, we
assessed the phenotypic consequences of interspecies gene flow. The
outcomes of our study shed light on the intricate evolutionary history
of modern balaenid whales, which have been profoundly shaped by ancient
climate events.