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Exceptionally prolonged tooth formation in elasmosaurid plesiosaurians.
Benjamin P Kear1, Dennis Larsson2, Johan Lindgren3
1Museum of Evolution, Uppsala University, Uppsala, Sweden.
Plos One
|February 28, 2017
Summary
Elasmosaurid plesiosaurians had slow tooth formation, taking 2-3 years per tooth. This prolonged odontogenesis may have influenced their feeding strategies and prey selection in Mesozoic seas.
Area of Science:
- Paleontology
- Marine Biology
- Vertebrate Zoology
Background:
- Elasmosaurid plesiosaurians were dominant marine reptiles in the Mesozoic Era.
- Their unique dentition, with long necks and fanged jaws, suggests specialized feeding, though details remain unclear.
Purpose of the Study:
- To determine tooth formation rates in elasmosaurid plesiosaurians.
- To understand how tooth development influenced their feeding ecology and functional morphology.
Main Methods:
- Analysis of dentine thin sections from isolated elasmosaurid teeth.
- Counting daily incremental lines of von Ebner to estimate tooth formation cycles.
Main Results:
- Elasmosaurid teeth exhibited an average of 950 daily incremental lines.
- This indicates a protracted tooth formation cycle of approximately 2-3 years, longer than other polyphyodont amniotes.
Conclusions:
- The slow tooth formation may relate to crown morphology, replacement constraints within bony crypts, and a diet of less robust prey.
- This prolonged odontogenesis likely played a role in elasmosaurid ecological specialization for specific aquatic predation.
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