Morphological Disparity of Ammonoids and the Mark of Permian Mass Extinctions

@article{Villier2004MorphologicalDO,
  title={Morphological Disparity of Ammonoids and the Mark of Permian Mass Extinctions},
  author={Loïc Villier and Dieter Korn},
  journal={Science},
  year={2004},
  volume={306},
  pages={264 - 266}
}
The taxonomic diversity of ammonoids, in terms of the number of taxa preserved, provides an incomplete picture of the extinction pattern during the Permian because of a strongly biased fossil record. The analysis of morphological disparity (the variety of shell shapes) is a powerful complementary tool for testing hypotheses about the selectivity of extinction and permits the recognition of three distinct patterns. First, a trend of decreasing disparity, ranging for about 30 million years, led… 
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