Gaiacia geniaeReaching a length of 4.5 metres, this newly discovered freshwater apex predator lurked in swamps and lakes some 280 million years ago. Its broad, flattened head was fitted with powerful jaws full of enormous fangs, ready to snatch any prey unlucky enough to swim past.
The problem is, based on what we know, this dinosaur couldn’t have been that big, it couldn’t have been extinct tens of millions of years before it was known to have lived, and it couldn’t have been found in northern Namibia.”Gaiacia “This is our first opportunity to get a good look at a completely different ecosystem that we didn’t expect,” says Jason Pardo, a postdoctoral researcher at the Field Museum of Natural History in Chicago. Gaiacia geniae The findings were recently published in the journal Nature.
Common ancestry
“Tetrapods are animals that crawled out of the water about 380 million years ago, or maybe a little earlier,” Pardo explains. These ancient creatures, also called stem tetrapods, are the common ancestor of modern reptiles, amphibians, mammals, and birds. “These animals survived until about 370 to 300 million years ago, which is called the end of the Carboniferous period. A few survived longer than that, but most of them became extinct about 370 million years ago,” he adds.
This is, Gaiacia geniae “It was amazing to find this dinosaur in the 280-million-year-old rocks of Namibia. Not only was it not extinct when the rocks in which it was found formed, it was dominating its ecosystem as an apex predator. By today’s standards, it was as if we’d stumbled upon an isolated island inhabited by, say, a living, breathing T-Rex, an animal that should have been extinct 70 million years ago.”
“skull Gaiacia “The fossil we found is about 67 centimetres long, and we also found the front part of the upper body. We know it was at least 2.5 metres, probably 3.5 or 4.5 metres long. It had a big head and a long body, kind of like a salamander,” Pardo said. Gaiacia She was a suction feeder: she would open her jaws underwater and create a vacuum to suck in prey. But her large, interlocking fangs reveal that she also had a powerful bite, which she probably used to hunt larger animals. “We Gaiacia Bony fish, freshwater sharks, and possibly other smaller Gaiacia“That suggests it was a rather slow-moving, ambush predator,” Pardo said.
But given where it was found, the fact that there was enough prey available to ambush it may be even more shocking than the animal itself.
Location, location, location
“The continents had a different configuration 270 to 280 million years ago,” Pardo says. At that time, one giant landmass called Pangaea had already split into two supercontinents: a northern supercontinent called Laurasia that included what are now parts of North America, Russia, and China; GaiaciaThis continent, called Gondwana, consisted of what are now India, Africa, South America, Australia, and Antarctica. And at that time, Gondwana was very cold.
“Some researchers hypothesize that the entire continent was covered with glaciers, similar to what was seen in North America and Europe during the ice age 10,000 years ago,” Pardo says. “Others argue that it was more fragmented, with some parts devoid of ice,” he adds. Still, 280 million years ago, northern Namibia was located around 60 degrees south latitude, roughly where the northernmost tip of Antarctica is today.
“Historically, we have seen that tetrapods [of that time] They lived a very similar life to modern crocodiles: they were cold-blooded, and if you’re cold-blooded, the only way you can get big and stay active is to be in a very hot environment. We used to believe that such an animal couldn’t survive in a cold environment. Gaiacia “It shows that this is absolutely not the case,” Pardo argues, and it upends much of what we knew about life on Earth. GaiaciaIt’s time.