The dinosaur with two fingers used its massive claws to devour leaves

A new species of dinosaur found on the Mongolian building site has the largest fully preserved claws ever discovered. The bipedal herbivores only had two fingers in each hand, so they may have been used to grab a branch and pull it towards their mouth.

The 90 million-year-old fossil containing parts of the pelvis, arms and hands, and parts of numerous vertebrae was discovered in 2012 near Kambogd in the Gobi Desert, but is now properly studied and given a scientific name. Duonychus tsogtbaatari. The genus name means “two claws” and the species name honors Mongolian paleontologists Kishigjav tsogtbaatar.

Duonychus It's a small relative of Tericinosaurusthe features of the movie Jurassic World Dominion. Yoshitug Kobayashi In Hokkaido, Japan, his colleague estimates that the dinosaurs were about 3 meters long and weighed about 270 kilograms.

“Discovery Duonychus tsogtbaatari It's a big deal because it's the first known tericinosaurus with only two fingers,” says Kobayashi.

Overall, five groups of theropods have evolved to have only two fingers. Tyrannosaurus.

DuonychusThe nails are nearly 30 centimeters. Unusually, the nail sheath is made of keratin, the same material as the nail – is preserved.

“Keratin usually doesn't become fossilized. It fades long before bones do it,” says Kobayashi. “Most of the time, when we find dinosaur claws, we just look at the nucleus of the bone. But in life, the actual claws are covered in thick keratin sheaths, which are longer and curved.”

Team Members Darla Zelenitsky At the University of Calgary, Canada, finding a two-fingered Tericinosaurus was very surprising.

“This is the largest 3D dinosaur claw that is completely preserved. “This claw is not preserved as the outline of the rock surrounding the bone. This is quite typical for fossils where the true claw is preserved. This claw is actually three-dimensional and forms a sheath around the underlying phalanx, similar to what is found on dog and cat's paws.”

Researchers believe that the nails are adaptations for grabbing and pulling down vegetation. Less fingers can make each one stronger, more flexible, narrower, and more controlled grips possible, Kobayashi says.

“The curved claws and extreme flexion suggest that they can be more easily connected to leaf branches and clusters,” he says. “Three fingers may have just got in the way, but two provided a more accurate and efficient grasp.”