Ancestral state reconstruction of ontogeny supports a bilaterian affinity for Dickinsonia

@article{Gold2015AncestralSR,
  title={Ancestral state reconstruction of ontogeny supports a bilaterian affinity for Dickinsonia},
  author={David A. Gold and Bruce Runnegar and James G. Gehling and David K Jacobs},
  journal={Evolution \& Development},
  year={2015},
  volume={17}
}
Despite numerous attempts, classification of the Precambrian fossil Dickinsonia has eluded scientific consensus. This is largely because Dickinsonia and its relatives are structurally simple, lacking morphological synapomorphies to clarify their relationship to modern taxa. However, there is increasing precedence for using ontogeny to constrain enigmatic fossils, and growth of the type species Dickinsonia costata is well understood. This study formalizes the connection between ontogeny in… 
Quantitative study of developmental biology confirms Dickinsonia as a metazoan
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This study demonstrates that Dickinsonia grew via pre-terminal ‘deltoidal’ insertion and inflation of constructional units, followed by a later inflation-dominated phase of growth, contrary to the widely held assumption that DickinsonIA grew via terminal addition of units at the end of the organism bearing the smallest units.
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TLDR
This work was funded by the Natural Environment Research Council, and an Australian Research Council Discovery Grant (DP0453393) to JGG.
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