Not a cheetah: Ancient DNA reveals the surprising Arctic life of extinct North American cat
New paleogenomics research by UC Santa Cruz reveals how the so-called American 'cheetah’ adapted to harsh Arctic conditions by preying on fish
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Illustration of a Miracinonyx trumani chasing after a Saiga antelope
view moreCredit: By Velizar Simeonovski
SANTA CRUZ, Calif. – A new study led by researchers at the University of California, Santa Cruz, has overturned decades of assumptions about Miracinonyx trumani, the extinct predator popularly known as the American cheetah.” By analyzing nuclear paleogenomes and stable isotopes from fossils found as far north as the Yukon, scientists have discovered that this iconic cat was not a true cheetah, but a highly adaptable relative of the puma that specialized in eating fish to survive the Arctic.
The findings, published on September 4 in Current Biology, reveal that the species’ range extended 20 degrees of latitude further north than previously recognized. While southern populations in regions like Wyoming and Florida lived as generalist predators in temperate grasslands, their northern counterparts in the Arctic Yukon carved out a unique niche as tertiary consumers, likely specializing in anadromous fish such as salmon.
With slender bodies and long front legs that may have helped them move efficiently across the open landscapes of Pleistocene North America, an adult Miracinonyx trumani was thought to weigh around 150 pounds on average and stand about 3 feet tall and measure about 8 feet long to the tip of its tail. Despite its cheetah-like appearance, this and other recent research suggest they were a versatile predator, capable of both terrestrial pursuit and grasping prey with powerful forelimbs.
“These cats were remarkably flexible, much like pumas are across their range today,” said Molly Cassatt-Johnstone, a Ph.D. candidate in the Paleogenomics Lab at UC Santa Cruz and lead author of the study. “We found loss-of-function mutations in certain genes that regulate circadian rhythms, suggesting they may have adapted to the extreme light cycles of summers and winters in northern latitudes.”
The ghosts of predators past
For decades, M. trumani has been a staple of North American paleoecology, often cited as the evolutionary reason why the American pronghorn is so fast. This “ghosts of predators past” hypothesis suggested that the pronghorn’s extreme speed was a co-evolved defense against the high-speed pursuit of a cheetah-like hunter.
However, the new genomic data confirm that M. trumani was actually a sister species to the modern puma, having diverged from that lineage roughly 2.6 million years ago. Its slender, “cheetah-like” body is now understood as a striking example of evolutionary convergence, where two unrelated species evolve similar traits to survive in similar environments.
Arctic adaptations and a lost sense of taste
By sequencing high-coverage genomes from fossils dating back 23,000 to 31,000 years, the team identified specific genetic blueprints that allowed these cats to thrive in the extreme environments of the Late Pleistocene.
Fossil specimens analyzed in this study from Yukon Territory were recovered from the Tr’ondëk Hwëch’in and Vuntut Gwitchin Traditional Territories, with respect for their deep-rooted relationship to and stewardship of these lands.
The study also revealed a unique sensory loss: M. trumani and all lineages of felids sampled in this study lacked a functional gene that encodes a receptor for sour taste. While all cats are known to lack a “sweet tooth,” this is the first recorded instance in felids of inactivation of genes involved in perception of sour flavors, a trait sometimes associated with highly specialized diets.
“This species of carnivore has this massive range, all the way from the Arctic to the Lower 48,” said co-author Matthew Wooller, a professor in the College of Fisheries and Ocean Sciences at the University of Alaska Fairbanks (UAF). “They’re demonstrating uber-specialization at two ends of their range, while also feeding on two completely different food sources.”
A legacy of low diversity
Beyond its diet and appearance, the study offers sobering insights into the species’ extinction at the end of the Pleistocene. The researchers found that M. trumani in Wyoming and the Yukon had low genetic diversity. But unlike pumas, their modern relatives, they didn’t show any signs of inbreeding or sharp bottlenecks—just a slow, long-term decline from the early to the late Pleistocene, which may explain their scarcity in the fossil record and ultimate extinction vulnerability.
Low genetic diversity didn’t doom this species by itself, said senior author Beth Shapiro, professor of ecology and evolutionary biology at UC Santa Cruz and co-director of the Paleogenomics Lab. “Miracinonyx persisted for a very long time without the signs of inbreeding we’d expect before a collapse,” she explained. “The decline was slow, not sudden, and that may be what left it unable to adapt when the climate shifted.”
The research highlights the danger of naming extinct species based solely on how they look. According to the authors, the name American "cheetah” is doubly misleading, as it implies a close relationship and a shared specialized hunting style that the data simply do not support.
This study was a collaborative effort involving researchers from UAF, the Yukon Palaeontology Program, and Des Moines University.
Miracinonyx radius recovered from Natural Trap Cave, Wyo.
Miracinonyx skull samples from Natural Trap Cave, Wyoming.
Credit
Julie Meachen
Usage Restric
Journal
Current Biology
Method of Research
Experimental study
Subject of Research
Animal tissue samples
Article Title
Range and diet diversity in the Pleistocene American "cheetah," Miracinonyx trumani
Article Publication Date
4-Sep-2026
COI Statement
Beth Shapiro is employed by and holds stock options in Colossal Biosciences.
The extinct American ‘cheetah’ was not a cheetah after all
Cell Press
image:
An artistic rendering of two Miracinonyx, one in Beringia preying mainly on fish and one in the Lower 48 feeding on pronghorn antelope.
view moreCredit: Julius Csotonyi
With their slender bodies and long front legs, Miracinonyx trumani—often nicknamed the “American cheetah”—was long thought to be a North American analog of the African big cat. But in a new study publishing September 4 in the Cell Press journal Current Biology, researchers reveal that the extinct cat was more closely related to pumas. Some populations living near the Arctic preyed almost exclusively on fish, challenging the long-held assumption that these “cheetahs” chased fast-running prey, such as pronghorns.
“It’s very hard to imagine a prehistoric species we’ve never seen without comparing it to something we know,” says Molly Cassatt-Johnstone, the paper’s first author from the University of California, Santa Cruz. “But this approach can limit our understanding of ancient animals’ complexity, unique evolutionary histories, and behaviors.”
The American cheetah roamed North America’s open grasslands during the Pleistocene epoch, about 2.5 million to 16,000 years ago. Based on fossils uncovered to date, M. trumani had a slender body shape, long forelimbs, and large nasal cavities—features that are characteristic of modern fast-running animals such as cheetahs or horses. In addition, paleontologists have discovered some M. trumani remains alongside those of pronghorns, fast-running animals known colloquially as the “American antelope," leading researchers to assume that the extinct cat had a similar lifestyle to modern African cheetahs.
However, in recent years, increasing evidence has suggested that M. trumani may not have been as cheetah-like as its appearance suggests. To delve deeper, Cassatt-Johnstone and her team sequenced the most complete M. trumani ancient DNA set to date from four specimens, one from Wyoming and three from Canada’s Yukon territory. The Yukon samples were previously thought to be a different species, but the team confirmed that they belong to M. trumani, extending the known range of M. trumani more than 20 degrees of latitude farther north than previously known.
The researchers then compared M. trumani’s DNA with that of nine other cat species, ranging from lions to house cats. They found that M. trumani shared a common ancestor with modern cheetahs about 4.7 million years ago. The species was most closely related to modern pumas, having diverged from a common ancestor about 2.6 million years ago.
Curious about what M. trumani ate in the absence of pronghorn, which aren’t found as far north as Canada’s Yukon territory, the team analyzed the nitrogen and carbon in the Yukon fossils to determine their diet and where they sat in the food chain.
The team found that despite being discovered in different locations and having lived hundreds of years apart, the Yukon M. trumani individuals all showed signals indicating that they preyed almost exclusively on fish. The fossils’ nitrogen profiles were similar to those observed in fish-specialist orcas and sea wolves living along the coast of British Columbia, which eat mainly marine animals. In contrast, the M. trumani in Wyoming had the nitrogen markers of a terrestrial predator that mostly eats herbivores, similar to lions.
The drastic range of M. trumani’s diet suggests that the animals were able to adapt to a variety of food sources. Such flexibility may have helped the species survive across diverse environments, from the subtropics to the Arctic, Cassatt-Johnstone says.
The researchers also found that two of M. trumani’s genes involved in circadian rhythm regulation were nonfunctional. These genes help control animals’ internal clocks, which use cues like sunlight to determine when to sleep. In M. trumani, the loss of these functional genes may suggest that populations living at high latitudes adapted to extreme periods of daylight and darkness, or that the animals were nocturnal.
“It’s really surprising and exciting to identify another predator present in Beringia,” Cassatt-Johnstone says, referring to the ancient land region connecting northeastern Asia and northwestern North America during the Pleistocene, where woolly mammoths and other large mammals roamed.
Like the woolly mammoth, M. trumani likely went extinct as the last ice age transitioned to the warmer Holocene.
“There are probably other extinct species that, unfortunately, have been reduced to fewer dimensions than they deserve,” Cassatt-Johnstone says. “The M. trumani fossils suggest that this ‘American cheetah’ was far more adaptable than its nickname implies.”
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This work was supported by the National Science Foundation, the Howard Hughes Medical Institute, and the National Institute of General Medical Sciences.
Current Biology, Cassatt-Johnstone et al., “Range and diet diversity in the Pleistocene American 'cheetah,' Miracinonyx trumani” https://www.cell.com/current-biology/fulltext/S0960-9822(26)01003-1
Current Biology (@CurrentBiology), published by Cell Press, is a bimonthly journal that features papers across all areas of biology. Current Biology strives to foster communication across fields of biology, both by publishing important findings of general interest and through highly accessible front matter for non-specialists. Visit: http://www.cell.com/current-biology. To receive Cell Press media alerts, contact press@cell.com.
Journal
Current Biology
Method of Research
Observational study
Article Title
Range and diet diversity in the Pleistocene American “cheetah”, Miracinonyx trumani
Article Publication Date
4-Sep-2026
An artistic rendering of Miracinonyx.
An artistic rending of Miracinonyx and the ecosystem they lived in.
Credit
Julius Csotonyi
