Halifax – Researchers have discovered a new species of old fish with anterior hooks hook, which made it a formidable and effective predator.
An article published this week in the Journal of Vertebrate Paleontology indicates that the long curved jaw of the animal makes it possible to understand the evolution of fish to smaller earlier teeth, acting as hooks, about 350 million years ago.
In addition, the posterior fangs, one centimeter long, were used to chew the prey before digesting them to make them a body that could measure almost a meter long. They hunted their prey in the interior waters of Nova Scotia, when it was probably at the time a large interior lake.
The main author, Conrad Wilson, doctoral student in paleontology at Carleton University, mentioned on Friday during an interview that the fish had been named Sphyragnathus Tyche, the first phrase signifying “hammer jaw”.
“I would say it is a fairly scary fish. If his mouth is open, we see these fangs in the jaw, “he described. But the fossil is also important for the indices it offers on the evolution of radiated fins, a group of vast and diverse vertebrates which occupies a wide variety of aquatic and semi-aquatic environments around the world.
“These fish were the last large group of vertebrates to be identified, and our knowledge of their early evolution is still largely incomplete,” said the researcher, who published his article with Chris Mansky, a fossil researcher at Blue Beach Fossil Museum in Hantsport, in Nova Scotia, and Jason Anderson, professor of anatomy Calgary.
“Fossils tell us about the appearance of fish that existed just after a massive extinction,” Wilson told the Devonian transition to carboniferous.
He adds that paleontologists wondered how the radiated fins recovered after this extinction period, while other groups of fish, such as the category of placoderms, with considerable armed defenses, disappeared. “The beach where this fossil has been discovered tells us that it is a group of animals that are doing well, fairly quickly, after a massive extinction,” he said.
The article hypothesizes that the methods of elaborate teeth feed could have played a role, creating an evolutionary advantage for the species.
Mr. Wilson noted that “this particular characteristic of the curved and pointed to the front and the front treatment at the rear has become a characteristic of many species thereafter.”
The area where the fossil was discovered – in Blue Beach, in the Minas basin, about 90 kilometers north of Halifax – was considered to be a large freshwater lake not far from the ocean.
The article of the research team attributes to Sonja Wood, former director of Blue Beach Fossil Museum, the merit of having discovered the fossilized jaw by inciting Mr. Mansky to go and check along a stream that spilled on the beach.
Ms. Wood, who died last year, was in a wheelchair and had urged her colleague to search the area. “She had a good feeling about what could be discovered (…) and she advised him to go see,” said Wilson.
“He went down and, indeed, the jaw fossil was there,” said the researcher, adding that Mr. Mansky had managed to recover the fossil before a storm strikes that night.
Wilson said that other discoveries were possible as the Blue Beach region was continued continuing.
“We have many different anatomies that have simply not been described yet. And we will work there in an article to be published in a few months, ”he said.
