Structural, functional, and physiological signals in ichthyosaur vertebral centrum microanatomy and histology

  title={Structural, functional, and physiological signals in ichthyosaur vertebral centrum microanatomy and histology},
  author={Alexandra Houssaye and Yasuhisa Nakajima and P. Martin Sander},
  pages={161 - 170}
ABSTRACT The first tuna-shaped amniotes evolved among ichthyosaurs, but this group exhibits in fact a wide diversity of morphologies and swimming modes. The histology and microanatomical features of vertebral centra of a diversity of ichthyosaur taxa from most basal to highly derived illustrating this variability were analyzed. The occurrence of unusual parallel fibered bone with platings of true parallel-fibered bone confirms high growth rate in all these taxa. Ichthyosaur vertebrae, which are… 

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