Study Finds 'American Cheetah' Was Actually a Puma Relative, Not a Cheetah

On September 4, a study in Current Biology redefines Miracinonyx trumani, previously known as the American cheetah, revealing its closer ties to modern pumas rather than cheetahs. Researchers examined four fossils from Wyoming and Yukon Territory in Canada, creating an evolutionary tree that indicates M. trumani diverged from puma ancestors approximately 2.6 million years ago and from cheetahs around 4.7 million years ago. This species existed during the Pleistocene epoch, spanning roughly 12,000 to 2.6 million years ago. Co-author Molly Cassatt-Johnstone from the University of California, Santa Cruz, noted that the name may not accurately reflect the species' behavior and ecology. The mislabeling began in 1979 due to observed similarities, with DNA evidence in 2005 suggesting a puma lineage. Analysis of nitrogen and carbon revealed that the Wyoming cat, which lived around 23,000 years ago, consumed herbivores like pronghorn, while Yukon specimens from about 31,000 years ago likely fed on fish such as salmon. The research team also identified mutations in circadian rhythm genes, indicating adaptations to extreme northern light conditions, and discovered a missing functional sour taste receptor gene found in lions and Canada lynx. Independent paleontologist Ross Barnett described the Arctic findings as a significant breakthrough.