This fancy fellow is a Tibetan Mastiff – a breed famed for its remarkable strength and endurance over 4.8-kilometre elevations. Evolutionary biologists have successfully identified the genes responsible for this adaptation, yet an elusive question remained: exactly how did they acquire the adaptation?
It turns out they bred with wolves.
A Chinese research group showed that Tibetan Mastiffs are much more closely related with other Chinese dogs rather than grey wolves. They also found two unique genomic hotspots, the EPAS1 and HBB loci, that show significant signals of interbreeding with the Tibet grey wolf.
The work was published in Molecular Biology and Evolution.
Tibetans repeated this interbreeding adaptation. Recent evidence shows that they may have also acquired their high-altitude adaptation by interbreeding with an ancient hominid known as the Denisovans.
Even in evolutionary biology, history may have a way of repeating itself.