A fishy mosasaur: the axial skeleton of Plotosaurus (Reptilia, Squamata) reassessed
The concept of convergence, that is, how unrelated animals independently evolve similar morphological traits, is a fundamental aspect of evolution. Hitherto, the Mesozoic ichthyosaurs were regarded as the sole obligate marine reptiles that achieved a fully streamlined body and a semilunate tail fluke. However, analyses of vertebral centrum morphometrics and process orientation have revealed that a