Birds, the only group of dinosaurs still alive today, have evolved to make themselves at home in just about everywhere. And then there are penguins, which plunge a quarter-mile deep into icy waters in search of food.
It now seems that modern birds are not the only dinosaur group to embrace the plunge-and-prey lifestyle. A team of researchers say they have found the earliest example of an extinct dinosaur with a body that was streamlined for diving. They described the dinosaur discovery in the journal Communications Biology.
The new duck-size dinosaur was at first overlooked. In 2008, Robin Sissons, then a master’s student at the University of Alberta, was on a dig in Mongolia’s Gobi Desert when she noticed a “string of white bits poking out of the rock.” After she shared a photo of what she had seen with her colleagues over lunch, they went to the spot and ultimately transported the fossil to South Korea for further study. (The fossil has since been returned to the Mongolian Academy of Sciences.)
“After preparation in Korea, a whole skeleton came to light,” said Yuong-Nam Lee of Seoul National University, who led the expedition and is an author of the study.
The researchers found the fossil had a mouth full of more than 100 tiny, sharp teeth and a long, slender neck. These features pointed to a dinosaur that spent time by the water, Lee said, with teeth, packed at the front of the snout, capable of hanging on to slippery, thrashing fish.
Similar fossils have also been found in Mongolia, including one called Halszkaraptor escuilliei, and scientists have debated whether it was semiaquatic. But the new dinosaur before Lee was better preserved than Halszkaraptor, especially in its ribs, which were slightly flattened and pointed toward the animal’s tail.
“Although the rib cage was not completely preserved, the rib orientation and shape clearly indicate that this animal had a streamlined body, as penguins do,” Lee said. This made the rib cage the smoking gun: Not only was this dinosaur feeding on fish, the researchers said, but it had a sleek body perfect for diving. The name they chose for it reflects this claim: Natovenator polydontus, “swimming hunter with many teeth.”
If the researchers are correct, Natovenator is among the first dinosaurs (besides birds) to dive for its dinner. — KATE GOLEMBIEWSKI/NYT