New fossil of a 252-million-year-old sabre-toothed lion shows it reigned just before mass extinction

A new fossil of a 252-million-year-old species of sabre-toothed lion that was discovered in the Karoo Basin in South Africa points to the apex predator’s reign for a short period, just prior to the Permian-Triassic mass extinction of 251.9 million-years-ago.

The fossil of the Inostrancevia africana, discovered by Jennifer Botha, Director of GENUS Centre of Excellence in Palaeosciences based at the University of the Witwatersrand (Wits) and a Professor at the Evolutionary Studies Institute at Wits is part of a group of predatory sabre-tooth protomammals, the gorgonopsians, went extinct well before the main extinction event. The new species is very similar to a Russian gorgonopsian, Inostrancevia alexandri, and was described in Current Biology, in a paper examining the rapid turnover of top predators in African terrestrial faunas around the Permian-Triassic mass extinction, of which Christian Kammerer, Research Curator in Palaeontology at the North Carolina Museum of Natural Sciences was the lead author.

Although all gorgonopsians were thought to have gone extinct by this stage, the new discovery shows that the open niche of top predators was taken by Inostrancevia, even if for a moment.

“These lion-sized carnivores turned out to be canaries in the coalmine for the Permo-Triassic mass extinction,” says Pia Viglietti, Research Scientist, and co-author at the Field Museum of Natural History in Chicago.

The reign of Inostrancevia in Africa was short-lived; relatively soon after its arrival, it went extinct and was itself replaced as a top predator by other groups of land vertebrates in rapid succession.

South Africa preserves the best fossil record of the terrestrial Permian-Triassic mass extinction 251.9 million years ago. It was the most catastrophic mass extinction in Earth’s history. Decades of research in the South African Karoo Basin have shown how devastating the land extinction was, causing numerous extinctions among vertebrates and a very unstable ecosystem.

Current evidence suggests that the primary driver of the extinction was global warming, ocean acidification, and habitat loss, because of massive volcanic activity.

“Given our problems with global warming and biodiversity loss today, these studies are important because the consequences of severe environmental change, such as global warming, can be studied and the information used to predict what we may face in the not-too-distant future,” says Botha.

“Apex predators in modern environments tend to show high extinction risk and tend to be among the first species that are locally extirpated due to human-mediated activities such as hunting or habitat destruction,” says Kammerer. “Think about wolves in Europe or tigers in Asia, species which tend to be slow to reproduce and grow and require large geographic areas to roam and hunt prey, and which are now absent from most of their historic ranges. We should expect that ancient apex predators would have had similar vulnerabilities and would be among the species that first go extinct during mass extinction events.”

Botha says the fieldwork that resulted in the discovery of this new species is part of a long-term project to examine the effects of this extinction on the biodiversity, biology and ecology of vertebrates living during this very difficult time.

“This shows that the South African Karoo Basin continues to produce critical data for understanding the most catastrophic mass extinction in Earth’s history,” says Botha.