Earth’s habitats were filled, for more than 150 million years, with dinosaurs of incredible species of all sizes and shapes. Giants with endless necks, carnivores with razor teeth, and birds in blinding colors proliferated in the post-Mesozoic years.
However, dinosaurs seem reluctant to enter the water despite their diversity and dominance. In two centuries of research and discoveries by paleontologists, no evidence has ever been found to indicate that the prehistoric giants could swim. The transition from land to water occurred during the later reptiles’ evolution. Now, however, scientists have discovered a new species of dinosaur that can swim.
The new species described Thursday (08/12) in the Communications Biology journal was not a giant lizard. About 71 million years ago, a little swimmer about 30 centimeters long thrived in ancient Mongolia. The aquatic dinosaur had an unusual, complex appearance and long jaws full of tiny teeth while being a “relative” of razor-toothed predators like Velociraptors. Paleontologist Sungjin Lee of Seoul National University and his colleagues named the dinosaur Natovenator polydontus (“swimming polydont hunter”).
A new species of dinosaur was discovered in the Gobi desert.
This new dinosaur species was discovered in the Gobi Desert, at a site known among paleontologists for preserving fossils of multiple species of dinosaurs and other prehistoric life forms, called Hermiin Tsav. Before the peculiar nature of this new species became apparent, careful preparation of its bones was required. After revealing these, Lee noted, “we realized this was something special.
It was well-preserved, with a well-formed skull and an extremely long neck.” Taking a closer look at the fossil, experts noticed that it shares some features with Halszkaraptor, the species discovered in 2017 and listed initially as aquatic.
The discovery of the dinosaur created much debate within the scientific community. Lee and the study’s co-authors scrutinized Natovenator’s bones and found that it was a swimmer. “We think it looked like a Cretaceous cormorant,” notes Lee.
Of course, paleontologists took millions of years to observe Natovenator to conclude how a dinosaur could swim. They should further determine how the prehistoric reptile’s anatomy affects its behavior. “Although the evidence is not entirely conclusive, I think some anatomical information from Natovenator gives us strong indications that it was probably an amphibious creature,” noted Argentine Museum of Natural Sciences paleontologist Federico Agnolin, who is not part of her team. of study.
Natovenator’s long jaws and many tiny teeth could have been used to grab small, spartan prey from the water. In addition, as the study authors note, its well-preserved sides slope backward, similar to penguins and glaucous birds. This spine arrangement is thought to have allowed Natovenator to swim more efficiently in Cretaceous lakes and streams. This kind of skeletal configuration has not been seen in any other known dinosaur species.
There are, of course, indications that there were amphibious dinosaurs – that is, they entered the water sporadically. Scratches attributed to other dinosaur species have been found in muddy sediments in various parts of the world. In most cases, theropod dinosaurs made these tracks as they crossed rivers or waded in the shallows in search of food.
As an amphibian, one of the largest species, Spinosaurus, has been recorded. However, the debate as to whether it was a keen swimmer or hunted underwater prey remains open. Its dense bones and crocodile-like jaws indicate that it could at least prowl the shallows in search of its next meal.
What has yet to be discovered is how prehistoric life swam. Although it looked like a cormorant, Natovenator appears to have swam on its forelimbs, in a primitive version of the locomotion of today’s amphibious birds such as penguins. Underwater, the same motions that birds use to fly are as helpful.