A fossil discovered on the southern coast of Japan in 2004 enabled a new species to be written into the Hadrosaur family today. The new species also provided some important information to the scientific world.
As the calendars show the year 2004, dinosaur remains were discovered on a small island off the south coast of Japan. Studies on this fossil, which is determined to belong to the Hadrosaur (duck-billed dinosaur) family, have continued to this day. Today, it has been announced that the fossil belongs to a previously undiscovered species.
This discovery, which expanded the family tree of the hadrosaur family, was made by the same team that discovered a species of the same family, named Kamuysaurus, in 2019. The previous fossil discovered with the last fossil is also the first dinosaurs discovered in Japan from the late Cretaceous period. This sheds light on which dinosaurs lived in Japan at the end of the dinosaur age.
A dinosaur that points to evolution from two-legged to four-legged:
There are some features that make the Yamatosaurus newcomer to the hadrosaur family unique in the family. Yamatosaurus has a different tooth structure compared to other species. Hadrosaurs had hundreds of teeth they carried on their cheeks, replacing as they wore or fell. The number and development of teeth in Yamatosaurus, on the other hand, is noticeably different. For this reason, it is thought that the species feeds on different plant species compared to other species.
In addition, scientists made another discovery that sheds light on the evolution of two-legged to four-legged species, along with the fossil. It was noticed that there was an ‘ unexpected development’ in the dinosaur’s shoulders and forelimbs. This unexpected development also pointed out that the dinosaur was in an evolutionary process. The new type of the Hadrosaur family, which was abundantly found in the Cretaceous period, thus created new question marks in the scientific world.
As for how dinosaurs migrated between two continents, scientists think that hadrosaurs crossed from Asia (Japan belonged to Asia 15 million years ago) to present-day Alaska over the Bering land bridge, which may have spread to almost all of North America.