First complete dinosaur skeleton from Japan: implications to the diversity of Asian dinosaurs prior to K/Pg boundary

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04052
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 17050:Biogeosciences-related
• Research Institution: Hokkaido University
• Principal Investigator: Kobayashi Yoshitsugu 北海道大学, 総合博物館, 教授 (70400033)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 恐竜

Outline of Final Research Achievements

The main results of this study was the naming of two genera of new dinosaurs (Kamuysaurus japonics and Yamatosaurus izanagii). These studies showed that high diversity of dinosaurs lived in Japan at the end of the dinosaur era, and further revealed the origin and evolution of the Hadrosauridae. A study of Yamatosaurus revealed that the origin of the Hadrosauridae was important in the easternmost region of Asia, including Japan, and a study of Kamuysaurus showed that the Hadrosauridae diversified in the North American coastline environment. The occurrences of dinosaur fossils from the marine deposits, where fossil records are rare in the world, is a characteristic of Japan and future research can be expected.

Free Research Field

古脊椎動物学

Academic Significance and Societal Importance of the Research Achievements

日本は、従来恐竜化石が少ないとされていた。特に、恐竜時代最末期の化石は少なく、恐竜の概念は欧米や中国・モンゴルを基としたものであり、日本の恐竜の世界が不明であった。しかし、本研究によって日本には多くの恐竜化石が眠っていることを示し、日本の恐竜が世界的にみても重要なものであることを示すことができた。