Cnn
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A new study has found evidence that at least one type of dinosaur may have been adept swimmers, diving into the water like a duck to stalk prey.
I study, Published in Communication biology On 1 December, he described a newly discovered species, Natovenator polydontus. The theropod, or hollow-bodied dinosaur with three toes and claws on each end, lived in Mongolia during the Late Cretaceous Period, 145 to 66 million years ago.
Scientists from Seoul National University, the University of Alberta and the Mongolian Academy of Sciences collaborated on the research.
The researchers noted that nattovenator had streamlined ribs, like those of diving birds.
“Its body shape suggests that Natovenator was an adept swimming predator and that the slender body evolved independently in separate lineages of theropod dinosaurs,” the authors wrote.
The natovinator specimen closely resembles Halszkaraptor, another dinosaur discovered in Mongolia, and scientists think it was likely semi-aquatic. But the Natovenator specimen is more complete than Halszkaraptor, making it easier for scientists to see its body’s streamlined shape.
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 difficult to pinpoint exactly where Natuvinator falls on the fully terrestrial to fully aquatic spectrum. But he said the specimen’s arms “seem to be very good at moving water.” Hon participated in a peer-reviewed study on the biology of communication.
Furthermore, the Natovenator had dense bones, which are essential for animals that dive below the surface of the water.
As the authors write, it had a “relatively hydrodynamic body.”
Hoon said the next step would be modeling the dinosaur’s body shape to help scientists understand exactly how it moved. “Is he paddling with his feet, some kind of fly swatter? How fast can it go?
Further research should also look into the environment in which 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 of these lakes will be difficult, but sooner or later we may find one. And when we do, we may find many more of these things.
Nizar Ibrahim, a senior paleontology professor at the University of Portsmouth whose research includes findings indicating that Spinosaurus was likely semiaquatic, told CNN he’s still not entirely 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 an animal’s bone density, bone histology, within a larger dataset,” he said. “Even the anatomy of the rib, if they put that into the bigger picture, the huge data set that would have been helpful.”
He said “the anatomical evidence is less clear” for a swimming nattovinator than for Spinosaurus.
And like Hone, he is curious as to exactly what waters the Natovenator may have swum. “The environment this animal was found in, in Mongolia, is the opposite of what one would expect from 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 is emerging to suggest 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 that not only have dinosaurs been around for a long time, but they’re also very diverse and very good at conquering a new environment.”
