Around 250 million years ago, widespread volcanic eruptions altered the Earth’s atmosphere and therefore its climate, triggering “The Great Dying”, otherwise known as the Permian extinction. Nine out of 10 species became extinct over roughly a million years, during which herbivores and predators maneuvered for resources, including the dreaded inostrancevia.
A saber-toothed meat-eater that likely had rhinoceros-thick skin and ran on all fours, the inostrancevia was the largest gorgonopsian, a group of proto-mammals that served as top predators in the years before the dinosaurs. Scientists thought the inostrancevia only lived in modern-day Russia, but the discovery of new fossils in South Africa means it must have migrated 7,000 miles across the supercontinent Pangea to reach a new home.
Researchers don’t know why the inostrancevia traveled so far from its original habitat, or how long the migration took.
“The fossils themselves were quite unexpected,” says co-author Pia Viglietti, a researcher at the Field Museum in Chicago, in a Press release.
Where did the saber-toothed animal go?
When inostrancevia arrived in the Karoo Basin in South Africa, it would have encountered few competitors as most had already disappeared, long before most other species, the study find. The predators there had served as canaries in the coal mine, the researchers said, and after leaving a fossil record, the inostrancevia also became extinct.
Learn more: The Permian extinction: Life on Earth nearly disappeared during the ‘Great Death’
Overall, the role of the top predator in the basin changed four times in less than 2 million years around the Permian extinction, “which is unprecedented in the history of life on earth”, explains co-author Christian Kammerer, curator of paleontology research at the Institute. North Carolina Museum of Natural Sciences, in a press release.
“This shows that South Africa’s Karoo Basin continues to yield critical data for understanding the most catastrophic mass extinction in Earth’s history,” says co-author Jennifer Botha, professor at Evolutionary Studies. Institute, in a press release.
Predators facing extinction
The basin also sheds light on how predators are disappearing in the modern world, where natural ranges are often shrinking due to human encroachment.
“Think of wolves in Europe or tigers in Asia, species that tend to be slow to reproduce and grow and require large geographic areas to move around and hunt prey,” says Kammerer. “Apex predators in modern environments tend to […] to be among the first species to disappear locally.
No one knows for sure whether gorgonopsians had reptile fur or skin, although it is believed that they hunted reptiles, particularly pareiasaurs, the largest lizards that lived during the Permian. Inostrancevia also ate dicynodonts, smaller pig-like relatives in the gorgonopsia clade.
Scientists have classified four-legged predators as therapsids, as well as creatures that have evolved into modern mammals. But inostrancevia most likely reproduces by laying eggs.