Pattern and process of serrations and denticles of reptilian teeth

爬行动物牙齿的锯齿和小齿的形态和过程

• 批准号: 09640560
• 负责人: MANABE Makoto
• 金额: $ 2.37万
• 依托单位: National Science Museum
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09640560/
• 关键词: Varanus; Iguana; Velociraptor; serration; denticle; intraspecific variations; morphometrics; 小鈍鋸歯; 歯; オオトカゲ; モルフォメトリックス

Size and shape of the serrations are often used as a diagnostic character in the theropod dinosaurs. There are very few studies of intraspecific variations of these characters. It is largely because there is not an appropriate method to describe the variations and to test them statistically. This study was to create digital image database for intraspecific variations and it was also to explore a suitable morphometric method. Two species of extant reptiles, Varanus and Iguana, and one species of an extinct reptile, Velociraptor, were chosen to measure tooth crown basal length, width, height, and serration or denticle basal length. Varanus was chosen because it is considered as one of the best analogues for theropod dinosaurs. Iguana was measured to made a comparison of its denticles to the serrations of Varanus. Velociraptor, a thropod dinosaur, was measured because it has a derived character in the serrations. Variations of serrations/denticles were the greatest among the four measurements taken in all the three species. A functional tooth in use shows differences in serration/denticle basal length from a replacement tooth in the same tooth position. The Velociraptor specimen did not show a derived character state. These findings strongly suggest that one should exercise caution on the use of characters on serrations and/or denticles. Several morphometric analyses were attempted to describe variations in dental characters. Due to high variations observed in serrations/denticles, morphometric methods turned out to be not suitable for the description.

锯齿的大小和形状通常被用作兽脚亚目恐龙的特征。这些性状的种内变异研究很少。这主要是因为没有一种适当的方法来描述这些变化并对其进行统计检验。本研究的目的是建立植物种内变异的数字图像数据库，并探索一种合适的形态测量方法。两种现存的爬行动物，巨蜥和鬣蜥，和一种灭绝的爬行动物，速龙，被选中测量齿冠基部的长度，宽度，高度，和锯齿或小齿基部长度。Varanus被选中是因为它被认为是兽脚亚目恐龙的最佳类似物之一。对鬣蜥进行测量是为了将它的锯齿与巨蜥的锯齿进行比较。速龙是一种步足类恐龙，被测量是因为它在锯齿上有一个衍生的特征。在所有三个物种的四个测量中，锯齿/锯齿的变化是最大的。使用中的功能性牙齿在锯齿/小齿基部长度上与相同牙齿位置中的替换牙齿显示出差异。迅猛龙标本没有表现出衍生的特征状态。这些研究结果强烈表明，在使用锯齿和/或锯齿上的字符时应谨慎。几种形态测量分析试图描述牙齿特征的变化。由于在锯齿/锯齿中观察到的高度变化，形态测定方法被证明不适合描述。

项目成果

Chure, D.J., Manabe, M., Tanimoto, M., and Y.Tomida: "An unusual theropod tooth from the Mifune Group (Late Cenomanian to Early Turonian), Kumamoto, Japan"Proceedings of the Second Gondwanan Dinosaur Symposium National Science Museum Monographs. (15). 291

Chure, D.J.、Manabe, M.、Tanimoto, M. 和 Y.Tomida：“日本熊本三船群（塞诺曼纪晚期到土伦纪早期）的一种不寻常的兽脚亚目恐龙牙齿”国家科学博物馆第二届冈瓦纳恐龙研讨会论文集

Chure,真鍋,谷本,冨田: "An unsual theropod tooth from the Mifune Group (Late Cenomanian to Early Turonian)"National Science Museum Monographs. 15. 291-296 (1999)

Chure，Manabe，Tanimoto，Tomita：“Mifune Group 的一种不寻常的兽脚亚目牙齿（晚塞诺曼阶到早期土伦阶）”国家科学博物馆专着 15. 291-296 (1999)。

真鍋真: "The early evolution of the Thrannosauridae in Asia"Jornal of Paleontology.. 73. 1176-1178 (1999)

Makoto Manabe：“亚洲Thrannosauridae的早期进化”Journal of Paleontology.. 73. 1176-1178 (1999)

Chure・真鍋・谷本・冨田: "An unsual theropod tooth from the Mifune Group(Late Cenomanian to Early Turonian), Kumamoto, Japan"National Science Museum Monographs. 15. 291-296 (1999)

Chure、Manabe、Tanimoto 和 Tomita：“日本熊本三船群（晚塞诺曼阶到早期土伦阶）的一种不寻常的兽脚类牙齿”国家科学博物馆专着。

Manabe, M.: "The early evolution of the Tyrannosauridae in Asia."Journal of Paleontology. 73(6). 1176-1178 (1999)

Manabe, M.：“亚洲暴龙科的早期进化。”古生物学杂志。