How to make a protostome

@article{Nielsen2012HowTM,
  title={How to make a protostome},
  author={Claus Nielsen},
  journal={Invertebrate Systematics},
  year={2012},
  volume={26},
  pages={25 - 40}
}
  • C. Nielsen
  • Published 19 June 2012
  • Biology
  • Invertebrate Systematics
Abstract. The origin and radiation of the major metazoan groups can be elucidated by phylogenomic studies, but morphological evolution must be inferred from embryology and morphology of living organisms. According to the trochaea theory, protostomes are derived from a holoplanktonic gastraea with a circumblastoporal ring of downstream-collecting compound cilia (archaeotroch) and a nervous system comprising an apical ganglion and a circumblastoporal nerve ring. The pelago-benthic life cycle… 

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