Computed tomographic analysis of the dental system of three Jurassic ceratopsians and implications for the evolution of tooth replacement pattern and diet in early-diverging ceratopsians
- China University of Geosciences, China
- The George Washington University, United States
- Chinese Academy of Sciences, China
Abstract
The dental system of ceratopsids is among the most specialized structure in Dinosauria by the presence of tooth batteries and high-angled wear surfaces. However, the origin of this unique dental system is poorly understood due to a lack of relative knowledge in early-diverging ceratopsians. Here we study the dental system of three earliest-diverging Chinese ceratopsians: Yinlong and Hualianceratops from the early Late Jurassic of Xinjiang and Chaoyangsaurus from the Late Jurassic of Liaoning Province. By micro-computed tomographic analyses, our study has revealed significant new information regarding the dental system, including no more than five replacement teeth in each jaw quadrant; at most one replacement tooth in each alveolus; nearly full resorption of the functional tooth root; and occlusion with low-angled, concave wear facets. Yinlong displays an increase in the number of maxillary alveoli and a decrease in the number of replacement teeth during ontogeny as well as the retention of functional tooth remnants in the largest individual. Chaoyangsaurus and Hualianceratops have slightly more replacement teeth than Yinlong. In general, early-diverging ceratopsians display a relatively slow tooth replacement rate and likely use gastroliths to triturate foodstuffs. The difference in dietary strategy might have influenced the tooth replacement pattern in later-diverging ceratopsians.
Data availability
All data generated or analysed during this study are included in the manuscript and supplementary file. We have uploaded the raw micro-CT scanning images of all scanned specimens (all cropped to the dentigerous regions) in Dryad as .TIF or .BMP file format and also the reconstructed 3D files (see the link https://doi.org/10.5061/dryad.9ghx3ffk0). The detailed information of all images is provided in a TXT file 'README_file.txt' saved in Dryad.
Article and author information
Author details
Funding
National Natural Science Foundation of China (41972021)
- Fenglu Han
National Natural Science Foundation of China (41688103)
- Xing Xu
National Natural Science Foundation of China (42072008)
- Qi Zhao
International Partnership Program of Chinese Academy of Sciences (132311KYSB20180016)
- Xing Xu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Yonatan Sahle, University of Cape Town, South Africa
Version history
- Received: December 29, 2021
- Preprint posted: January 19, 2022 (view preprint)
- Accepted: April 19, 2022
- Accepted Manuscript published: April 20, 2022 (version 1)
- Version of Record published: May 4, 2022 (version 2)
Copyright
© 2022, Hu et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Computed tomographic analysis of the dental system of three Jurassic ceratopsians and implications for the evolution of tooth replacement pattern and diet in early-diverging ceratopsians
eLife 11:e76676.
https://doi.org/10.7554/eLife.76676
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