Reinterpretation of Yunnanozoon as the earliest known hemichordate

@article{Shu1996ReinterpretationOY,
  title={Reinterpretation of Yunnanozoon as the earliest known hemichordate},
  author={De-gan Shu and X. Zhang and L. Chen},
  journal={Nature},
  year={1996},
  volume={380},
  pages={428-430}
}
THE Chengjiang fossil Lagerstätte is one of the earliest and most important palaeontological sites from the Phanerozoic era1,2, about 530 million years ago3. It yields extremely abundant and remarkably preserved soft-bodied fossils and shells with soft parts of various kinds, including bradoriids4–6, trilobites7,8, crustaceans9, brachiopods, worms, sponges, algae and many unknown forms10–13. One of these fossils is Yunnanozoon14, which we reinterpret here as the earliest known hemichordate… 
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