A new study has found evidence that at least one type of dinosaur may have been an adept swimmer, diving into the water like a duck to stalk its prey.
the study, Posted in Biology of Communications On December 1, he described a newly discovered species, Natovenator polydontus. The theropod, or hollow-bodied dinosaur with three fingers and claws at each end, lived in Mongolia during the Late Cretaceous, between 145 and 66 million years ago.
Scientists from Seoul National University, the University of Alberta and the Mongolian Academy of Sciences collaborated on the paper.
The researchers noted that the nattovenator had streamlined ribs, like those of diving birds.
“Its body shape suggests that Natovenator was a predator capable of swimming, and that the streamlined body evolved independently in separate lineages of theropod dinosaurs,” the authors wrote.
The natovinator specimen resembles Halszkaraptor, another dinosaur discovered in Mongolia, and scientists believe it was likely semi-aquatic. But the Natovenator specimen is more complete than Halszkaraptor, making it easier for scientists to see the streamlined shape of its body.
The researchers explain that both Natovenator and Halszkaraptor used their arms to propel themselves through the water.
David Hone, a paleontologist and professor at Queen Mary University of London, told CNN that it’s hard to pinpoint exactly where Natuvinator falls on the spectrum, from all terrestrial to fully aquatic. But he said the arms in the sample “look like they’re going to be pretty good at moving water.” Hon participated in a peer-reviewed study on the biology of communication.
Additionally, Natovenator had dense bones, which are essential for animals to dive below the surface of the water.
As the authors write, it had a “relatively hydrodynamic body.”
Hoon said the next step would be to model the shape of the dinosaur’s body to help scientists understand exactly how it moved. “Is he paddling with his feet, a bit like a dog paddle? How fast can you go?»
Further research should also look at the environment in which the Natuvinator lived. The specimen was discovered in the Gobi desert in Mongolia, but there is evidence that lakes and other bodies of water existed in the desert in the past.
“There’s a real question, well you have a dinosaur swimming in the desert, what is it swimming in?” He said. “Finding the fossil record for those lakes is going to be hard, but sooner or later we might find one. And when we do, we might find a lot of these things.”
Nizar Ibrahim, a senior professor of paleontology at the University of Portsmouth, whose research includes findings indicating that Spinosaurus was likely semi-aquatic, told CNN that he is still not fully convinced by the study’s findings. He argued that a more rigorous quantitative analysis would have made the results more convincing.
“I wanted to see, for example, a really robust description of bone density, the bone histology of an animal, within a larger data set,” he said. “Even the anatomy of the ribs, if they put it into a bigger picture, the massive data set that would have been useful.”
He said that “the anatomical evidence is less clear” for a swimming nattovinator than it is for Spinosaurus.
And like Hone, he’s also curious as to exactly what waters the Natovenator might have been swimming in. “The environment this animal was found in, in Mongolia, is somewhat the opposite of what you would expect for a water-loving animal,” he said.
But he hopes the study will help open the door to broader insights into dinosaur behavior. Dinosaurs were once thought to be purely terrestrial, but mounting evidence suggests that at least some species spent as much time in the water as they did on land.
“I’m sure there will be many, many surprises,” Ibrahim said. “And we’ll find out that dinosaurs have not only been around for a long time, but they’re also, you know, very diverse and very good at conquering a new environment.”