Origins of Bilateral Symmetry: Hox and Dpp Expression in a Sea Anemone

@article{Finnerty2004OriginsOB,
  title={Origins of Bilateral Symmetry: Hox and Dpp Expression in a Sea Anemone},
  author={John R. Finnerty and Kevin Pang and Patrick M. Burton and David Paulson and Mark Q. Martindale},
  journal={Science},
  year={2004},
  volume={304},
  pages={1335 - 1337}
}
Over 99% of modern animals are members of the evolutionary lineage Bilateria. The evolutionary success of Bilateria is credited partly to the origin of bilateral symmetry. Although animals of the phylum Cnidaria are not within the Bilateria, some representatives, such as the sea anemone Nematostella vectensis, exhibit bilateral symmetry. We show that Nematostella uses homologous genes to achieve bilateral symmetry: Multiple Hox genes are expressed in a staggered fashion along its primary body… 

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Early origin of the bilaterian developmental toolkit

  • D. Erwin
  • Biology
    Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2009
It is suggested that placozoans and cnidarians represent a depauperate residue of a once more diverse assemblage of early animals, some of which may be represented in the Ediacaran fauna (c. 585–542 Myr ago).
...

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