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Ancient DNA evidence narrows down when people first reached the Americas
Confirmed
In Short: Researchers have discovered that the extinct predator known as the American cheetah was actually a relative of the modern puma, not the African cheetah.
The findings, published in the journal Current Biology, were based on ancient DNA and stable isotopes from fossils found in the Yukon, Canada.
Lead author Molly Cassatt-Johnstone, a Ph.D. candidate at the University of California, Santa Cruz, explained that the American cheetah was long thought to be closely related to the African cheetah due to its elongated legs and large sinuses, adaptations for high-speed pursuit.
However, Cassatt-Johnstone and her colleagues analyzed four of the most complete sets of Miracinonyx trumani DNA found to date, revealing a closer genetic relationship to pumas.
The study also uncovered surprising details about the American cheetah's diet, suggesting that some northern populations were linked closely to fish, a diet not typically associated with large predators.
Cassatt-Johnstone noted that the Pleistocene Beringia, a well-studied paleontological ecosystem, now includes this new carnivore.
She emphasized that the American cheetah's diet was highly flexible, allowing it to adapt to different environments and resources.
The research team combined high-coverage ancient genomes with radiocarbon dating and stable-isotope measurements to reconstruct the cat's evolutionary history and diet.
The study provides new insights into the evolutionary history and dietary flexibility of the American cheetah, challenging previous assumptions about its relationship to modern cheetahs and pumas.
Researchers suggest that the Wyoming and Yukon populations of the American cheetah remained connected relatively late into the Pleistocene, indicating a broader distribution than previously thought.
What's confirmed
- The findings, published in the journal Current Biology, were based on ancient DNA and stable isotopes from fossils found in the Yukon, Canada.
- Lead author Molly Cassatt-Johnstone, a Ph.D. candidate at the University of California, Santa Cruz, explained that the American cheetah was long thought to be closely related to the African cheetah due to its elongated legs and large sinuses, adaptations for high-speed pursuit.
- However, Cassatt-Johnstone and her colleagues analyzed four of the most complete sets of Miracinonyx trumani DNA found to date, revealing a closer genetic relationship to pumas.
- The study also uncovered surprising details about the American cheetah's diet, suggesting that some northern populations were linked closely to fish, a diet not typically associated with large predators.
- Cassatt-Johnstone noted that the Pleistocene Beringia, a well-studied paleontological ecosystem, now includes this new carnivore.
- She emphasized that the American cheetah's diet was highly flexible, allowing it to adapt to different environments and resources.
- The research team combined high-coverage ancient genomes with radiocarbon dating and stable-isotope measurements to reconstruct the cat's evolutionary history and diet.
- The study provides new insights into the evolutionary history and dietary flexibility of the American cheetah, challenging previous assumptions about its relationship to modern cheetahs and pumas.
- Researchers suggest that the Wyoming and Yukon populations of the American cheetah remained connected relatively late into the Pleistocene, indicating a broader distribution than previously thought.
What's still developing
- For example, these ancient cats had elongated legs and large sinuses, both classic adaptations for chasing prey at high speeds, according to Cassatt-Johnstone.
- “That was kind of the first understanding of this species,” she said.
- When the researchers first received the 23,000- to 31,000-year-old specimens, they thought they might be pumas, as paleontologists had found remains of those cats in the region before.
- But scientists’ understanding of this ancient predator has changed in recent years, and now, researchers have uncovered surprising new details about the species.
- When the American cheetah was first named and officially described in 1979, fossil evidence pointed to its strong convergent morphology, or shared features, with modern cheetahs.
- Paleontologists studying a fossil unearthed in southern Manitoba, Canada, have identified what they believe are two bite marks on the internal skeleton of the ancient giant cephalopod Enchoteuthis, offering rare evidence of predator-prey interactions in the Cretaceous seas that once covered the middle of North America.
- Both a mosasaur such as Latoplatecarpus, and a predatory fish such as Cimolichthys, lived alongside Enchoteuthis in the same ancient seaway and remain plausible culprits.
- The American cheetah ( Miracinonyx trumani ) stalked North America’s Pleistocene grasslands for nearly 2.5 million years, but new evidence suggests they likely didn’t resemble their present-day African namesake.
- Berinigia is the ancient stretch of land that once connected northeastern Asia to northwestern North America.
- Ancient DNA shows the American “cheetah” was a puma relative, while Yukon fossils reveal a surprising diet linked to fish. (CREDIT: Shutterstock) The extinct predator known for decades as the “American cheetah” may have been one of the most misunderstood large cats of Ice Age North America.
- Instead, it was the sister lineage of the puma, while chemical evidence from fossils in Canada's Yukon suggests some northern populations occupied an extraordinary ecological niche linked closely to fish.
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