In the Bluefish Caves and a mine site in northern Yukon, bones initially believed to be from an ice-age puma or cougar were examined through DNA analysis by the University of California. Molly Cassatt-Johnstone, a lab technician fresh out of her undergrad studies, conducted the testing on the Yukon bones, revealing they were not pumas as expected but were, in fact, cheetahs.
Grant Zazula, a Yukon paleontologist, vividly recalled his surprise upon receiving the news that the creatures were actually cheetahs and not cougars. The discovery marked a significant shift in the understanding of ancient DNA research, which was once considered science fiction but has now become a routine practice in analyzing permafrost-preserved bones.
Cassatt-Johnstone made history as the first to identify a Yukon Miracinonyx, also known as the extinct American cheetah. Her findings, detailed in a paper published in Current Biology, provided new insights into the ice-age cat’s diet and habitat.
Researchers previously believed the American cheetah hunted pronghorns on grassy plains, but the discovery of these animals in the Arctic tundra puzzled experts. Through stable isotope analysis, the study revealed that the Yukon cheetahs primarily subsisted on fish, a behavior uncommon among historical and contemporary feline species.
Julie Meachen, a paleontologist specializing in mammalian carnivores, noted the unique dietary habits of the Yukon cheetahs compared to their counterparts in other regions. In a landscape teeming with formidable predators, including massive Beringian lions and giant short-faced bears, the cheetahs likely capitalized on the abundant Yukon salmon runs for sustenance.
Genetic analysis showed that Miracinonyx was genetically closer to North American pumas than African cheetahs, with low genetic diversity indicating a small population size that may have contributed to their extinction. Zazula proposed renaming this distinctive northern population from ‘American Cheetah’ to ‘Yukon Cheetah’ to reflect their Arctic fishing adaptations and evolutionary history.
The ongoing discoveries in the Yukon underscore the endless potential for new revelations in paleontology, emphasizing that each bone unearthed has the potential to unveil a previously unknown chapter in the region’s prehistoric past.