Explaining the Cambrian "Explosion" of Animals

  title={Explaining the Cambrian "Explosion" of Animals},
  author={Charles R. Marshall},
  journal={Annual Review of Earth and Planetary Sciences},
  • C. Marshall
  • Published 28 April 2006
  • Environmental Science
  • Annual Review of Earth and Planetary Sciences
The Cambrian “explosion” is a unique episode in Earth history, when essentially all the animal phyla first appear in the fossil record. A variety of environmental, developmental (genetic), and ecological explanations for this complex and somewhat protracted event are reviewed, with a focus on how well each explains the observed increases in disparity and diversity, the time of onset of the radiation, its duration, and its uniqueness. The increase in disparity (the origin of the phyla) and… 

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