According to researchers, this is the first time that a non-avian theropod, a type of carnivorous dinosaur that walks on two legs, has been discovered, so the finding could mean a change in what was known so far about dinosaurs.
Scientists in Mongolia discovered a new dinosaur fossil that was likely a semi-aquatic diving predator , a bird-like specimen and was named “Natovenator polydontus” or “many-toothed swimming hunter,” as they described it.
Researchers with the Korea-Mongolia International Dinosaur Expedition located the fossils in the Baruungoyot Formation in 2008 , said Young-Nam Lee, a professor of vertebrate paleontology who led the excavation.
During the expedition, 27 team members collected 196 cataloged specimens . The Natovenator polydontus was found by Robin Sissons, a graduate student at the University of Alberta, Lee said.
#NSTworld The dinosaur, called Natovenator polydontus, lived about 72 million years ago during the Cretaceous Period and was built like a diving bird with a streamlined body while possessing a goose-like elongated neck.#Dinosaur #Mongolia #Bird https://t.co/6NC1tMYgat
— New Straits Times (@NST_Online) December 1, 2022
The fossil was not fully exposed in the field, so Sissons, despite not knowing what it was at the time, made a plaster cover for it, Lee said.
All of the fossils in that collection were then shipped to South Korea for preparation and study, where “a complete skeleton” of the new dinosaur species came to light, Lee said.
The specimen “was so delicate but beautifully preserved,” Lee said.
It included a skull, vertebral column, a forelimb, and the remains of two hindlimbs. Its streamlined body, with ribs pointing toward its tail, is similar to that of modern diving birds, and its long neck resembles modern waterfowl such as geese, the researchers said. These adaptations may have reduced the resistance that the Natovenator would have been subjected to when swimming, helping it to catch prey.
Meet Natovenator polydontus. It's a newly discovered species of dinosaur that had a streamlined body like a diving bird https://t.co/LEATG8c4Wt
— New Scientist (@newscientist) December 1, 2022
The fossil also included an “unusually high number of teeth” compared to the size of the dinosaur’s jaw, indicating that it ate a diet based on fish or insects, according to the researchers.
“We instantly knew it was something important,” Lee said. “It had a skull with many small teeth and a very long neck was distinctive .”
This is the first time a non-avian theropod, a type of meat-eating dinosaur that walks on two legs, with a streamlined body similar to that of some birds , has been discovered , according to the researchers.
“Natovenator is a valuable discovery,” Lee said. “Finding semi-aquatic dinosaurs means that ecological diversity was very high in dinosaurs.”