A recent study reveals intriguing insights into the catastrophic “Great Dying” extinction event 252 million years ago, focusing on the role of a tiger-sized, saber-toothed creature called Inostrancevia.
Unearthed fossils indicate that this creature migrated 7,000 miles across Pangaea, filling a gap left by extinct top predators in a far-flung ecosystem before becoming extinct itself. Originally only found in Russia, these creatures were unexpectedly discovered in South Africa’s Karoo Basin. Their extinction prior to the main event suggests that apex predators could serve as early indicators of impending mass extinctions. Researchers draw parallels between these prehistoric patterns and current ecological crises, underscoring the importance of understanding ancient extinction events to predict and possibly mitigate today’s biodiversity loss.
Two hundred and fifty-two million years ago, Earth experienced a mass extinction so devastating that it’s become known as “the Great Dying.” Massive volcanic eruptions triggered catastrophic climate change, killing off nine out of every ten
The prehistoric creature looked the part of “top predator.” “Inostrancevia was a gorgonopsian, a group of proto-mammals that included the first saber-toothed predators on the planet,” says Viglietti. It was about the size of a tiger and likely had skin like an elephant or a rhino; while vaguely reptilian in appearance, it was part of the group of animals that includes modern mammals.
Prior to this new paper, Inostrancevia had only ever been found in Russia. But while examining the fossil record of South Africa’s Karoo Basin, Viglietti’s colleague Christian Kammerer identified the fossils of two large predatory animals that were different from those normally found in the region. “The fossils themselves were quite unexpected,” says Viglietti. It’s not clear how they made it from what’s now Russia, or how long it took them to cross Pangaea and arrive in what’s now South Africa. But being far from home was just one element of what made the fossils special.
“When we reviewed the ranges and ages of the other top predators normally found in the area, the rubidgeine gorgonopsians, with these Inostrancevia fossils, we found something quite exciting,” she says. “The local carnivores actually went extinct quite a bit before even the main extinction that we see in the Karoo– by the time the extinction begins in other animals, they’re gone.”
The arrival of Inostrancevia from 7,000 miles away and its subsequent extinction indicates that these top predators were “canaries in the coal mine” for the larger extinction event to come.
“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 co-author Jennifer Botha, director of GENUS Centre of Excellence in Palaeosciences and professor at the Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg.
“We have shown that the shift in which groups of animals occupied apex predator roles occurred four times over less than two million years around the Permian-
The vulnerability of these top predators matches what we see today. “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.”
In addition to shedding new light on the extinction event that helped lead to the rise of the dinosaurs, Viglietti says that the study is important for what it can teach us about the ecological disasters the planet is currently experiencing.
“It’s always good to get a better understanding of how mass extinction events affect ecosystems, especially because the Permian is basically a parallel on what we’re going through now,” said Viglietti. “We don’t really have any modern analogs of what to expect with the mass extinction happening today, and the Permo-Triassic mass extinction event represents one of the best examples of what we could experience with our climate crisis and extinctions. I guess the only difference is, we know what to do and how to stop it from happening.”
Reference: “Rapid turnover of top predators in African terrestrial faunas around the Permian-Triassic mass extinction” by Christian F. Kammerer, Pia A. Viglietti, Elize Butler and Jennifer Botha, 22 May 2023, Current Biology.
DOI: 10.1016/j.cub.2023.04.007