A couple of studies published yesterday in the journal PeerJ revealed the discovery of two very special fossils. The newfound remains belong to ancient predators that go back a long way, to millions of years before the time of the dinosaurs.
Co-authored by Christian Kammerer, from the North Carolina Museum of Natural Sciences in Raleigh, U.S., and Vladimir Masyutin, a researcher at the Vyatka Paleontological Museum in Kirov, Russia, the two papers describe previously unknown species of prehistoric saber-toothed creatures that roamed the Earth during the Permian Period (approximately 299-252 million years ago).
The newfound species were part of a diverse group of proto-mammals called therapsids — the distant ancestors of all mammal species alive today, reports Phys.org.
Belonging to different subgroups of therapsids, the saber-toothed creatures were unearthed in Russia, from a fossil-rich Permian site near the town of Kotelnich in European Russia.
“Kotelnich is one of the most important localities worldwide for finding therapsid fossils — not only because they are amazingly complete and well-preserved there, but also because they provide an all-too-rare window into mammal ancestry in the Northern Hemisphere during the Permian,” said Kammerer.
Named After Monsters
The two saber-toothed predators whose remains emerged from the Kotelnich site were truly the stuff of nightmares. In fact, these creatures were so fearsome that they were named after legendary monsters from Russian folklore, notes Newsweek.
One of the newfound species was dubbed Gorynychus masyutinae, after the three-headed dragon Zmey Gorynych.
According to the PeerJ study describing this ancient fossil, Gorynychus belonged to the therapsid subgroup called therocephalians, which literally means “beast heads.” This prehistoric carnivore was roughly the size of a modern-day wolf but represented the apex predator of its ecosystem.
The other saber-toothed “monster” was given the name Nochnitsa geminidens, in reference to a malevolent nocturnal spirit. The name choice was motivated by the fact that Nochnitsa was likely a nocturnal creature, given that its skull had relatively large eye sockets.
As per the PeerJ paper documenting this second species, the terrifying beast belonged to the subgroup called gorgonopsians, translating to “gorgon faces.” The researchers show that Nochnitsa was smaller than Gorynychus and represented a long-snouted carnivore with needle-like teeth.
The newly discovered saber tooth fossils are significant for two reasons. Firstly, they are among the few Permian therapsids to be found outside of South Africa, which has yielded the vast majority of proto-mammalian remains hailing from the Permian Period.
Secondly, they date back to a very interesting point in time, marked by decisive changes that have gone on to shape the evolution of modern mammals.
These prehistoric predators lived during a transition period between two major mass extinction events, the mid-Permian extinction (260 mya) and the end-Permian extinction (252 mya), which almost annihilated all proto-mammals.
The curious thing about these extinction events is that they produced a shift in the evolution of therapsid predators.
During the mid-Permian, the apex predators were all therocephalians, just like Gorynychus, whereas gorgonopsians were smaller carnivores, similar to Nochnitsa.
However, in the late-Permian, these therapsid subgroups had reversed their balance of power, gorgonopsians becoming the top predators and therocephalians evolving into small insectivore proto-mammals.
Kammerer chimed in on the situation.
“In between these extinctions, there was a complete flip-flop in what roles these carnivores were playing in their ecosystems — as if bears suddenly became weasel-sized and weasels became bear-sized in their place.”
The researchers are hoping that the newfound saber tooth fossils — which represent the first-ever evidence that this turnover among ancient predators was not confined to South Africa — could shed some light into the matter and help solve this Permian puzzle.