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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The advent of animals: The view from the Ediacaran
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  • Geography, Environmental Science
    Proceedings of the National Academy of Sciences
  • 2015
TLDR
It is shown that, although in appearance, these organisms look very strange and unfamiliar, many of them may have had a biology and/or ecology similar to animals today, and some were most certainly bilaterians, cnidarians, and poriferans.
Host-specific infestation in early Cambrian worms
TLDR
New worm associations suggest the earliest known record of aggregate infestation of the integument of a soft-bodied bilaterian, host specificity and host shift in the early Cambrian of China, which may represent the earliest evidence for host-specific infestation in bilaterians.
Megaevolutionary dynamics in reptiles and the role of adaptive radiations in evolutionary innovation
TLDR
A strong decoupling between phenotypic and molecular rates of evolution is found, with many periods of accelerated phenotypesic evolution or expansion of phenotyping disparity at the origin of major reptile clades and body plans that do not correspond to periods of adaptive radiation.
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