The “American Cheetah” Was No Cheetah: Ancient DNA Reveals Its True Legacy

Tens of thousands of years ago, a long-legged feline nicknamed the “American cheetah” prowled the landscapes of North America. However, a fresh analysis of the cat family tree reveals that this prehistoric predator’s closest living relatives are actually pumas, researchers report in Current Biology.

This genetic revelation challenges the animal’s famous nickname. For decades, the moniker suggested a highly specialized, high-speed hunter akin to the modern African cheetah, built to chase down fleet-footed prey like the American pronghorn, which can reach speeds of nearly 90 kilometers per hour. However, a growing body of genetic evidence indicates that Miracinonyx trumani, the so-called American cheetah, is much more closely related to the modern puma. Unlike the specialized African cheetah, pumas are remarkably versatile opportunistic hunters, capable of taking down large hoofed animals like deer and elk, as well as small rodents and raccoons.

New fossil findings from Canada’s Yukon Territory suggest that M. trumani itself was far more adaptable than previously thought. The extinct Pleistocene predator inhabited North American grasslands from approximately 2.5 million to 16,000 years ago. While previous fossils were concentrated in the southern plains and northern grasslands, newly analyzed remains from the Yukon expand the species’ known range significantly further north. Chemical analysis of these northern fossils reveals a surprising dietary habit: these northern cats may have dined almost exclusively on aquatic prey.

“Calling it the American cheetah implies a specific behavior and ecology, which isn’t necessarily appropriate for this species,” explains Molly Cassatt-Johnstone, a molecular ecologist at the University of California, Santa Cruz.

The discovery was somewhat accidental. Cassatt-Johnstone and her colleagues initially set out to use ancient genetic material to verify the identity of three roughly 31,000-year-old fossils from the Yukon. Because of their extreme northern location, researchers had tentatively classified the remains as belonging to pumas. However, once the team successfully extracted and sequenced the ancient DNA, the genetic data told a different story.

“It wasn’t until we were able to generate the genetic data that we were able to identify them as American cheetahs,” Cassatt-Johnstone notes. “Then, that led to this whole discovery avalanche.”

The genetic analysis, which combined DNA from the Yukon specimens with another M. trumani fossil from Wyoming’s Natural Trap Cave, confirmed that the American cheetah’s closest living relative is indeed the puma. The two lineages diverged from a common ancestor around 2.6 million years ago. In contrast, M. trumani and modern cheetahs split much earlier, roughly 4.7 million years ago.

To understand how these northern cats survived without the pronghorn typically associated with their image, the team turned to chemical clues preserved in the bones. By analyzing isotopes of nitrogen, the researchers could reconstruct the predator’s position in the food chain. Predators that consume other animals accumulate a heavier isotope of nitrogen, whereas plant-eating prey have lower levels.

The Wyoming specimens showed heavy nitrogen levels consistent with a terrestrial carnivore that preyed on herbivores. In stark contrast, the Yukon specimens displayed nitrogen isotope ratios comparable to marine predators like orcas, which sit at the top of a long aquatic food chain. This suggested that the northern M. trumani may have eaten almost exclusively fish.

One of the Yukon fossils was even discovered in a cave that contains numerous Pleistocene fish fossils, supporting the idea that aquatic prey was readily available. “It’s clear that the resource was around and that they could have been exploiting it, which is awesome,” Cassatt-Johnstone says.

It remains unclear whether the northern cats actively fished or simply scavenged carcasses along riverbanks. However, chasing large, fast land prey carries a high risk of injury for carnivores, such as crushed skulls or failed hunts. Switching to abundant, less dangerous aquatic resources presents a highly effective survival strategy.

“If they’re able to exploit a prey resource that is abundant and doesn’t cause them significant injury, that’s a win-win,” remarks Larisa DeSantis, a paleoecologist at Vanderbilt University who was not involved in the study. “It’s really cool to see that sort of adaptability in the American cheetah.”

Looking ahead, analyzing more specimens from across the species’ range—particularly south of Wyoming—could further illuminate just how adaptable the “American cheetah” truly was. This ongoing research suggests that the familiar nickname may have long obscured the complex and flexible reality of this extinct feline.

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