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Published on: March 29, 2018
The evolution of dinosaur tooth enamel microstructure
1Department of Anatomy, New York College of Osteopathic Medicine, Old Westbury, 11568-8000, USA. shwang01@nyit.edu
Summary
Dinosaur tooth enamel microstructure (schmelzmuster) evolution shows stepwise changes, with simpler enamel in basal taxa preceding complex forms in derived dinosaurs. This study enhances understanding of dinosaur evolution and phylogeny.
Area of Science:
- Paleontology
- Evolutionary Biology
- Vertebrate Zoology
Background:
- Mammalian tooth enamel microstructure is well-documented, but reptilian, including dinosaur, enamel microstructure remains poorly understood.
- Previous research established that dinosaur schmelzmuster aids clade diagnosis, correlates with tooth complexity, and shows homoplasy in Theropoda but not Ornithischia.
Purpose of the Study:
- To fill taxonomic gaps in previous dinosaur tooth enamel microstructure studies.
- To reinforce existing conclusions on dinosaur schmelzmuster utility and evolution.
- To investigate stepwise evolution of schmelzmuster within major dinosaur clades.
Main Methods:
- Microstructural examination of tooth enamel from 28 additional dinosaur taxa.
- Comparative analysis of enamel microstructure complexity and schmelzmuster across diverse dinosaur clades.
- Correlation of dental and enamel character evolution within the Euornithopoda clade.
Main Results:
- New specimens reinforce previous findings on schmelzmuster diagnostic utility and complexity correlations.
- Basal taxa within Sauropodomorpha, Neotheropoda, and Euornithopoda exhibit simpler enamel, evolving into more complex forms in derived taxa.
- Schmelzmuster evolution proceeds in a stepwise manner, with specific correlations observed in Euornithopoda.
Conclusions:
- Tooth enamel microstructure provides crucial insights into dinosaur evolutionary patterns and relationships.
- Stepwise evolution of schmelzmuster is evident in several dinosaur clades, with basal forms acting as precursors.
- Thorough sampling, particularly of basal members within clades, is essential for understanding dinosaur enamel evolution.
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