The newly discovered dinosaur looks like a nightmare goose
Paleontologists discovered 71-a million-year-old carnivorous dinosaur in southern Mongolia that they believe they had a body built for swimming and diving for prey. Although it closely resembles a modern bird, it is not actually an avian dinosaur, meaning it is likely an example of convergent evolution, a phenomenon in which unrelated beings develop similar traits.
The dinosaur is called Natovenator polydontus, or “swimming hunter with many teeth.” A recent analysis of it fossilized remains show the animal was bipedal and made for diving. Full description of the newly discovered animal iwith published in Communication Biology.
“Finding semi-aquatic dinosaurs means that ecological diversity was very high in dinosaurs,” Yuong-Nam Lee, a paleontologist at Seoul National University and lead author of the study, writes in an email to Gizmodo. “More than 30 different lineages of tetrapods have independently invaded aquatic ecosystems. Why not dinosaurs?”
Besides his many teeth, N. polydontus he had a slender body and a long neck. From the ass up, the extinct dinosaur may have looked a lot like a goose or cormorant, modern a diving bird, but it had a long tail. The skeleton is incomplete – researchers found its skull, spine, forelimb and some of the two hind limbs – but the animal’s morphology can be inferred from the remains found.
“The angle between each rib and its associated articulated vertebra is very low, like many diving birds, but unlike terrestrial theropods,” Lee said. “Some extant diving birds—such as alcids and phalacrocoracids–also have backward extending ribs. In these animals, the backward-facing ribs aid swimming by making the body more streamlined.
Lee’s team hopes so they can find the contents of the bird’s stomach to learn more about its diet. This kind of discovery is not without precedent; last year, paleontologists discovered on a fossilized marine equivalent of the turducken in modern Germany.
Also last year, a different team made up of many of the same researchers behind the new paper announced the discovery of an armored ankylosaurus from the same region in Mongolia. They placed that ankylosaurs may have dug defensive trenches when threatened, a lot like modern horned lizards.
More fossils will need to be found to better test these ideas, but taken together, the fossils show the dynamism of biodiversity during the Cretaceous.