Theoretical Modeling of Ammonoid Morphology

  • Takashi Okamoto
Part of the Topics in Geobiology book series (TGBI, volume 13)


Theoretical morphology, which was first developed by Raup and Michelson (1965). is a means of describing the morphological spectra of extant and fossil organisms using a mathematical growth model. Raup (1966, 1967) simulated the three-dimensional morphology and growth pattern of marginally growing molluscan shells by several simple parameters and reproduced these shell shapes with the aid of computer graphics. His approach can be applied not only to interpret the functional and adaptive constraints of morphology but also to analyze morphogenesis. With the recent development of the computer and its graphic techniques, the theoretical morphological approach becomes useful for understanding the morphology of extant and extinct animals including ammonoids.


Shell Growth Shell Morphology Neutral Buoyancy Life Orientation Body Chamber 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • Takashi Okamoto
    • 1
  1. 1.Department of Earth SciencesEhime UniversityMatsuyama 790Japan

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