Six major steps in animal evolution: are we derived sponge larvae?

@article{Nielsen2008SixMS,
  title={Six major steps in animal evolution: are we derived sponge larvae?},
  author={Claus Nielsen},
  journal={Evolution \& Development},
  year={2008},
  volume={10}
}
  • C. Nielsen
  • Published 1 March 2008
  • Biology, Medicine
  • Evolution & Development
A review of the old and new literature on animal morphology/embryology and molecular studies has led me to the following scenario for the early evolution of the metazoans. [...] Key Result The evolution of multicellularity enabled division of labor between cells, and an "advanced choanoblastaea" consisted of choanocytes and nonfeeding cells. Polarity became established, and an adult, sessile stage developed. Choanocytes of the upper side became arranged in a groove with the cilia pumping water along the groove…Expand
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Early animal evolution: a morphologist's view
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  • Medicine, Biology
    Royal Society Open Science
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