The Avalon Explosion: Evolution of Ediacara Morphospace

@article{Shen2008TheAE,
  title={The Avalon Explosion: Evolution of Ediacara Morphospace},
  author={B. Shen and L. Dong and S. Xiao and M. Kowalewski},
  journal={Science},
  year={2008},
  volume={319},
  pages={81 - 84}
}
Ediacara fossils [575 to 542 million years ago (Ma)] represent Earth's oldest known complex macroscopic life forms, but their morphological history is poorly understood. A comprehensive quantitative analysis of these fossils indicates that the oldest Ediacara assemblage—the Avalon assemblage (575 to 565 Ma)—already encompassed the full range of Ediacara morphospace. A comparable morphospace range was occupied by the subsequent White Sea (560 to 550 Ma) and Nama (550 to 542 Ma) assemblages… Expand
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TLDR
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The end of the Ediacara biota: Extinction, biotic replacement, or Cheshire Cat?
TLDR
The demonstration of geographic and niche range changes offers a novel means of assessing the downfall of Ediacara-type taxa at the hands of emerging metazoans, which is hypothesize to be most likely due to the indirect ecological impact metazans had upon the Ediacarans. Expand
Fractal branching organizations of Ediacaran rangeomorph fronds reveal a lost Proterozoic body plan
TLDR
Using parametric Lindenmayer systems, a formal model of rangeomorph morphologies reveals a fractal body plan characterized by self-similar, axial, apical, alternate branching, and an adaptive radiation based on 3D space-filling strategies. Expand
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