In the Bluefish Caves and a mining site in northern Yukon, bones initially believed to be from an ice-age puma or cougar were recently reevaluated through DNA analysis conducted by the University of California. Molly Cassatt-Johnstone, a former lab technician, conducted the tests on these Yukon bones early in her career, leading to a surprising discovery that they were not pumas but cheetahs.
Grant Zazula, a Yukon paleontologist, vividly recalls the moment he learned about this revelation that the ‘cougars’ were actually cheetahs. The identification of a Yukon Miracinonyx, known as the extinct American cheetah, marked a significant milestone for Cassatt-Johnstone, who is now the lead author of a paper published in Current Biology shedding new light on the ice-age cat’s diet and habitat.
The study challenged previous beliefs about the American cheetah’s behavior, suggesting that they were not specialized predators of American pronghorn antelope as previously assumed. Instead, their presence in the Arctic tundra puzzled researchers due to the absence of pronghorns in Beringia, the region where Asia and North America once connected.
To unravel the mystery of how Miracinonyx survived in this environment, researchers utilized stable isotope analysis, a technique commonly used in forensics to investigate dietary habits and environmental conditions. Surprisingly, the study revealed that Yukon cheetahs primarily fed on fish, a behavior uncommon among past and present-day cats.
This discovery has led to a reevaluation of the species, suggesting that the Yukon cheetahs may have adapted to a diet of salmon due to the abundance of fish in the region. Furthermore, genetic analysis indicated that Miracinonyx was genetically closer to North American pumas than African cheetahs, with a low genetic diversity that may have contributed to their extinction.
Grant Zazula proposes renaming this unique northern population from ‘American Cheetah’ to ‘Yukon Cheetah’ to reflect their distinct habitat and behavior. The findings highlight the importance of continuous exploration and research in paleontology, as every discovery, no matter how small, can unveil a new chapter in the history of ancient species.
