2024-07-24 インペリアル・カレッジ・ロンドン(ICL)
<関連情報>
- https://www.imperial.ac.uk/news/255014/komodo-dragons-have-iron-coated-teeth-apart/
- https://www.nature.com/articles/s41559-024-02477-7
鉄でコーティングされたコモドドラゴンの歯と肉食爬虫類の複雑な歯のエナメル質 Iron-coated Komodo dragon teeth and the complex dental enamel of carnivorous reptiles
Aaron R. H. LeBlanc,Alexander P. Morrell,Slobodan Sirovica,Maisoon Al-Jawad,David Labonte,Domenic C. D’Amore,Christofer Clemente,Siyang Wang,Finn Giuliani,Catriona M. McGilvery,Michael Pittman,Thomas G. Kaye,Colin Stevenson,Joe Capon,Benjamin Tapley,Simon Spiro & Owen Addison
Nature Ecology & Evolution Published:24 July 2024
DOI:https://doi.org/10.1038/s41559-024-02477-7
Abstract
Komodo dragons (Varanus komodoensis) are the largest extant predatory lizards and their ziphodont (serrated, curved and blade-shaped) teeth make them valuable analogues for studying tooth structure, function and comparing with extinct ziphodont taxa, such as theropod dinosaurs. Like other ziphodont reptiles, V. komodoensis teeth possess only a thin coating of enamel that is nevertheless able to cope with the demands of their puncture–pull feeding. Using advanced chemical and structural imaging, we reveal that V. komodoensis teeth possess a unique adaptation for maintaining their cutting edges: orange, iron-enriched coatings on their tooth serrations and tips. Comparisons with other extant varanids and crocodylians revealed that iron sequestration is probably widespread in reptile enamels but it is most striking in V. komodoensis and closely related ziphodont species, suggesting a crucial role in supporting serrated teeth. Unfortunately, fossilization confounds our ability to consistently detect similar iron coatings in fossil teeth, including those of ziphodont dinosaurs. However, unlike V. komodoensis, some theropods possessed specialized enamel along their tooth serrations, resembling the wavy enamel found in herbivorous hadrosaurid dinosaurs. These discoveries illustrate unexpected and disparate specializations for maintaining ziphodont teeth in predatory reptiles.
