Japanese Fossils Challenge Our Understanding Of Hadrosaur Evolution

Hadrosaurs were among the most successful dinosaur families of the late Cretaceous. If it weren’t for that anxious asteroid / comet they would be the most common large vegetable in the world today.

However, a new discovery reveals that we probably made a mistake in thinking something about the key aspects of their development. Famous for their duck-like bill, hydrocephalus dominated North America 73-66 million years ago, much larger than predatory predators and larger-than-sized sauropods.

Last year we learned that they made it before the world in Africa because they knew it would stop a crash. Who knows more about how common they can become there, given more time? The first hadrosaur fossils were discovered in North America, and it was later widely believed that they were the place that developed before most of the conquest of the world. However, the discovery of a new species called Yamatosaurus izanagii in a scientific report on the sound of the island of Japan has called it into question.

Japan was still attached to Asia 71-72 million years ago when Yamatosaurus was alive – its island status is only 15 million years old. Although dating to the end of the dinosaur reign, Yamatosaurus’ features indicate that it was a broad relative break from the hadrosaur line. Its dividers further consider that this family initially developed in Asia, and only later moved to the continent where they were most successful. The most recognizable chewers snouts had hundreds of teeth placed, making them champion cheers.

These teeth were as seamlessly replaceable as sharks; the backup was growing when a tooth came out of the work of breaking down such a tough plant. Yamatosaurus was different from every other hadrosaur we found, with no effective replacement available for most of its teeth. Combined with the difference in tooth size from the hadrosaur norm, Hokkaido University Museum Professor Yoshitsugu Kobayashi led them to live on a diet different from their peers, although we don’t know what that was.

Japan lacks open fossil-rich outputs that have provided most of us with knowledge of critiques, so Kobayashi and co-authors were thrilled to see an elsewhere with the vertebrae of the jaws, teeth, shoulders, and neck and tail of one of the Awaji today. Nevertheless, hadrosaurid fossils of Awaji have been found along the four main islands of Japan, indicating how common they were. However, the jaw and teeth have proven to be a particularly valuable piece of evidence.