Reports of a mass extinction of the “Gorgons” at the end of the Permian period were greatly exaggerated, new research finds. These bizarre paleo-beasts were thought to have been extinct along with most other living things on Earth by that time, but scientists recently found that some of these so-called gorgons survived into the Triassic period. They didn’t survive long, however, making them a “dead group that walks,” the team said.
An analysis of three specimens found in the Karoo Basin of South Africa shows that this group of saber-toothed animals known as gorgonopsians were the dominant Late Period predators permianShe managed to survive the “Great Dying”. During this event, which took place around 251.9 million years ago and is also known as the End-Permian extinction, about 90% of all species became extinct. Gorgonopsians were an exception – but despite their survival, their prospects were not great.
“‘Dead Clade Walking’ is a term used in extinction studies to refer to when a group of organisms technically survives a mass extinction but is so damaged by it that they never recover and linger for a while before eventually disappearing .” project worker Christian Kammerer (opens in new tab)the research curator of paleontology at the North Carolina Museum of Natural Sciences in Raleigh, told Live Science in an email.
The migration of dead clades can continue for millions of years after a mass extinction, “but never again diversify or reach significant abundance in ecosystems such that they are effectively already ‘dead’ from a macroevolutionary perspective,” he explained.
The research was presented at the Society of Vertebrate Paleontology’s annual conference in Toronto on November 3 and has yet to be published in a peer-reviewed journal.
Related: Ancient saber-toothed ‘Gorgons’ bit each other in ritualized combat
Gorgonopsians—named for the mythical and monstrous Greek gorgons whose appearance could turn humans to stone—existed long before the dinosaur Formed during the Triassic, about 240 to 230 million years ago.
The researchers were aware of a partial Gorgonopsian skull from the Karoo Basin that was dated to the Induanian age of the Triassic period (251.9 million to 251.2 million years ago). Other researchers had discarded this skull, thinking it had been misidentified or misdated. But new research found it was “definitely a gorgonopsian,” possibly of the genus Cyonosaurus, said Kammerer and lead author Julien Benoit (opens in new tab)a senior researcher in paleontology at the Evolutionary Studies Institute at the University of the Witwatersrand in Johannesburg.
The duo then analyzed two other specimens, likely also members of Cyonosaurus, from the Karoo Basin. Of the three Gorgonopsian specimens, two are from sites spanning the Permo-Triassic boundary and the third is from an Early Triassic layer.
It is possible that Cyonosaurus survived the mass extinction due to its small size, abundance, and flexible diet. The fox-sized carnivore – which had a narrow, elongated snout studded with teeth – was one of the smallest known gorgonopsians in existence. Small, generalist predators tend to adapt better to changing ecosystems than large, specialized predators and are therefore more likely to survive catastrophic events, Kammerer said. “So if there was one gorgonopsian that we would expect to survive into the Triassic, this would be it Cyonosaurus,” he said.
After the mass extinction, biodiversity in the Karoo Basin collapsed, and a tusked herbivore called Lystrosauruswho lived during parts of the Permian and Triassic, the numbers skyrocketed, “So, Cyonosaurus probably didn’t run out of loot,” Benoit told Live Science in an email.
Research is ongoing and “further examination of these sites is needed,” the team said. But the data suggests that gorgonopsians survived into the earliest part of the Triassic, which is about as surprising as a tyrannosaur surviving the asteroid that struck Earth, the scientists joked in their conference summary .
However, Triassic gorgonopsians were rare and belonged to a single genus, so this dead walking group “should still be considered victims of the mass extinction event at the end of the Permian,” the researchers said.