Tooth histology in the cretaceous ichthyosaur Platypterygius australis, and its significance for the conservation and divergence of mineralized tooth tissues in amniotes
| Autor: | Erin E. Maxwell, Michael W. Caldwell, Denis O. Lamoureux |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Extinction
Biological stomatognathic system Convergent evolution Ichthyosaur medicine Animals Cementum Dental Cementum Ophthalmosauridae biology Enamel paint Australia Reptiles Histology Anatomy biology.organism_classification Biological Evolution Cretaceous stomatognathic diseases medicine.anatomical_structure visual_art Dentin visual_art.visual_art_medium Animal Science and Zoology Platypterygius Tooth Tooth Calcification Developmental Biology |
| Zdroj: | Journal of Morphology. 272:129-135 |
| ISSN: | 0362-2525 |
| DOI: | 10.1002/jmor.10898 |
| Popis: | Ichthyosaurs are an extinct group of secondarily aquatic reptiles that show ligamentous tooth attachment to the jaw in some derived forms. Here, we provide a modern description of tooth histology in ichthyosaurs, using Platypterygius australis, a large ichthyosaur from the Cretaceous of Australia. Our study supports evolutionary conservation of the principal mineralized tooth tissue types in amniotes with ligamentous tooth attachment: enamel, dentine, cellular, and acellular cementum. This is the first time that the latter tissue has been located in ichthyosaurs. Vascularized cementum (osteocementum) is reduced or absent in amniotes in which the teeth are ankylosed to the jaw bone, such as basal ichthyosaurs, and raises questions regarding the function of this tissue and the potential developmental or selective conditions leading to its convergent evolution. J. Morphol., 2011. © 2010 Wiley-Liss, Inc. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text