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The morpho-mechanical basis of ammonite form.
D E Moulton1, A Goriely1, R Chirat2
1Mathematical Institute, University of Oxford, Oxford, UK.
Journal of Theoretical Biology
|September 27, 2014
Summary
This study introduces a morpho-mechanical model explaining ammonite rib formation and diversity. The model reveals intrinsic links between shell geometry and ribbing, offering new insights into cephalopod evolution.
Area of Science:
- Paleontology
- Evolutionary Biology
- Biophysics
Background:
- Ammonites, extinct cephalopods, are crucial for understanding biochronology, paleobiology, and evolutionary theories.
- Their spiral shell geometry and ribbing patterns are key features for inferring phylogenetic relationships and evolutionary trends.
Purpose of the Study:
- To develop the first quantitative morpho-mechanical model for ammonite shell morphogenesis, specifically focusing on rib formation.
- To provide a natural explanation for the diversity and development of ammonite ribs based on growth and mechanics.
Main Methods:
- Development of a novel morpho-mechanical model for ammonite shell growth.
- Application of fundamental principles of biological growth and mechanical forces to simulate morphogenesis.
Main Results:
- The model successfully explains the morphogenesis and diversity of ribs in ammonites.
- Identified intrinsic laws connecting ammonite ribbing patterns with shell geometry.
- Established a quantitative framework for analyzing ammonite shell form.
Conclusions:
- The morpho-mechanical model offers a new perspective on ammonite shell development.
- Provides a foundation for reinterpreting ammonite evolutionary trends and the evolution of other shelled mollusks.
- Highlights the interplay between growth, mechanics, and form in biological evolution.
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