Rethinking the American Cheetah
For decades paleontologists called Miracinonyx trumani the “American cheetah” because its slender frame, elongated limbs, and open‑grassland habitat resembled the African sprint‑specialist. New genetic work, however, has upended that nickname, revealing a creature far closer to the modern cougar (puma) than to any true cheetah.
DNA from Fossils Redraws the Family Tree
Researchers from the University of California, Santa Cruz and collaborators extracted ancient DNA from fossilized bones unearthed in Wyoming and the Yukon. By comparing these sequences with those of living felids, they placed M. trumani on the cat phylogeny with unprecedented precision. The analysis shows the species diverged from the lineage that gave rise to today’s puma roughly 2.6 million years ago, confirming a close evolutionary relationship.
Convergent Evolution, Not Direct Ancestry
The striking morphological similarity to cheetahs is now understood as a classic case of convergent evolution—different lineages independently evolving comparable traits to thrive in similar environments. As lead author Molly Cassatt‑Johnstone notes, “Comparing a prehistoric animal to a familiar modern one can be misleading and limit our perception of extinct life.”
A Vast Northern Range and an Unexpected Diet
DNA also helped identify three Yukon specimens that had previously been misassigned, extending the known range of M. trumani far into the Arctic. While Wyoming individuals show isotopic signatures typical of terrestrial carnivores that hunted antelopes and other ungulates, the Yukon fossils tell a different story. Their carbon and nitrogen ratios point to a diet rich in aquatic prey, most likely migratory salmon.
This marine‑based feeding habit persisted across multiple sites and time periods, suggesting that northern populations regularly exploited fish resources. How these predators captured slippery prey remains a mystery, but the evidence underscores their ecological flexibility.
Implications for Paleobiology
The study, published in *Current Biology*, reshapes our understanding of North American megafauna. It demonstrates that visual resemblance alone can mask deep genetic divergence, and it highlights the importance of integrating molecular data with traditional morphology.
In addition to overturning a long‑standing nickname, the research opens new questions about the hunting strategies of extinct felids and the role of aquatic food webs in shaping their evolution.
Source: https://scientias.nl/de-amerikaanse-cheeta-blijkt-helemaal-geen-cheeta-te-zijn-geweest/