In the Bluefish Caves and a mine site in northern Yukon, bones initially thought to be from an ice-age puma or cougar were reanalyzed through DNA testing conducted by Molly Cassatt-Johnstone from the University of California. The results surprised her, revealing that the bones were not from cougars but from cheetahs.
Grant Zazula, a Yukon paleontologist, vividly recalls the moment he received the unexpected news that the bones were from cheetahs, not cougars. This discovery marked a significant breakthrough in ancient DNA analysis, a process that was once considered science fiction but is now a routine practice in studying permafrost-preserved bones from the Yukon.
Cassatt-Johnstone’s identification of a Yukon Miracinonyx, also known as the extinct American cheetah, led to her becoming the first author of a paper published in Current Biology. The study sheds new light on the ice-age cat’s diet and range, challenging previous beliefs about the animal’s habitat and hunting behavior.
The American cheetah was traditionally thought to have evolved to chase pronghorns on grassy plains, but its presence in the Arctic tundra puzzled researchers. Beringia, the land connecting Asia and North America that includes parts of Russia, Alaska, and the Yukon, served as a unique habitat for these cheetahs. Researchers turned to stable isotope analysis to unravel how the Miracinonyx survived in such an environment.
The study revealed that Yukon cheetahs predominantly fed on fish, a behavior uncommon among past and present-day cats. This dietary preference was likely influenced by the abundance of Yukon salmon, providing an easy food source in a region teeming with large predators like Beringian lions and giant bears.
Genetic analysis showed that Miracinonyx was more closely related to North American pumas than African cheetahs. The study also highlighted the low genetic diversity and population numbers of these cats, which may have contributed to their eventual extinction.
Zazula suggests renaming this distinct northern population from ‘American Cheetah’ to ‘Yukon Cheetah’ in light of the new discoveries. The findings underscore the importance of continued exploration and analysis of ancient remains to uncover the rich history of prehistoric species in the region.
