Spirula—a window to the embryonic development of ammonoids? Morphological and molecular indications for a palaeontological hypothesis

  title={Spirula—a window to the embryonic development of ammonoids? Morphological and molecular indications for a palaeontological hypothesis},
  author={K. Warnke and H. Keupp},
Nautilus is not suitable as a model organism to infer biological functions, embryonic development, or mode of life in ammonoids. A brief review of the available morphological data is given and molecular data are added to discuss the usefulness of Spirula as a biological proxy for ammonoids. Indeed, there are many morphological hints indicating that Spirula could be a useful model organism for approaching the embryonic development of ammonoids. The molecular data seem to support this hypothesis… Expand

Paper Mentions

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