Fossil teeth of Heptranchias sp. occurred from the Middle Miocene Nanao calcareous sandstone Member in Nanao City, Ishikawa Prefecture, Hokuriku area, Japan. The records of this genus in the Middle Miocene of Japan have been limited to the Tokai and Kanto regions on the Pacific side, but this discovery reveals that the genus was came into the Sea of Japan by that period.

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  X-ray CT (CT: X-ray computed tomography) and X-ray μCT (μCT: X-ray micro-computed tomography) are characterized by the fact that the sample to be studied can be analyzed non-destructively without cutting or slicing. Here, the research results on the tissue structure of the jawbone of Eusthenopteron foodi (Devonian, Canadian), modern sperm whale teeth and Miocene horse molars, Pliocene marine mammal penile bones, human premolar cementum and jawbones and teeth of Mosasaurus sp. (Cretaceous, Morocco) are exhibited. Using various methods such as X-ray CT, X-ray μCT, micro-Raman spectroscopy, and FE-SEM, the detailed internal structure, the composition and constituent crystals of hard tissue can be analyzed in a more multidimensional manner.

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  The idea that birds’ ancestors are bipedal theropod dinosaurs is now accepted. But there have been various theories about the origin of avian flapping flight for more than a century, and there is still no theory that convinces everyone. The basis of the conventional theories is critically examined here, and a new rationale is presented. Therefore, the method of vertebrate paleobiology for the purpose of restoration and elucidation of evolution is used. Actually, the most plausible hypothesis was already presented long ago, and the evidence of fossils needed to support it has been found. There has been no reasonable basis to maintain otherwise. Animal locomotion is the movement of the center of gravity of the body. The center of gravity of the body is on the legs of bipedal dinosaurs and at the base of the wings that produce lift in flying animals. In the evolution from dinosaurs to birds, the center of gravity of the body must shift from the pelvis to the chest. In conclusion, the tetrapteryx theory of Beebe makes the most sense, and now Anchiornis from the Jurassic of Liaoning Province, China is the most informative fossil.

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 わが国最初の足跡化石の報告は，篠本二郎が長崎県北松浦郡佐々町江里免の中新世の地層から発見した三趾型の奇蹄類であると，1894年（明治27年）地質学雑誌第２巻第15号に記録されている．足跡化石は，それ以来，今日まで中生代と新生代の地層から徐々に発見され，報告されているが，体化石と比べればまだまだごく僅かと言える．
 1988年（昭和63年），滋賀県南部の鮮新世の地層からゾウ類，シカ類，サイ類，ワニ類の足跡化石が発見され研究が進み，国内の産地が急に増加してきた．2019年（令和元年）現在，日本の始新世，中新世，鮮新世，更新世の産地は約190箇所である．筆者は，過去32年間，国内の新生代の地層からの足跡化石を観察してきた．そして，足跡を残した動物はゾウ類，サイ類，シカ類，イノシシ類，ワニ類，鳥類，種類未確定の四趾型哺乳類であることを確認している．ここでは，その中の鮮新−更新世からの典型的かつ明瞭な足跡化石とその他の生痕化石を報告する．

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