The Cambrian Conundrum: Early Divergence and Later Ecological Success in the Early History of Animals

@article{Erwin2011TheCC,
  title={The Cambrian Conundrum: Early Divergence and Later Ecological Success in the Early History of Animals},
  author={Douglas H. Erwin and Marc Laflamme and S M Tweedt and Erik A. Sperling and Davide Pisani and Kevin J. Peterson},
  journal={Science},
  year={2011},
  volume={334},
  pages={1091 - 1097}
}
Major animal clades evolved tens of millions of years before the widespread appearance of animal fossils. Diverse bilaterian clades emerged apparently within a few million years during the early Cambrian, and various environmental, developmental, and ecological causes have been proposed to explain this abrupt appearance. A compilation of the patterns of fossil and molecular diversification, comparative developmental data, and information on ecological feeding strategies indicate that the major… 

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