Hooking some stem‐group “worms”: fossil lophotrochozoans in the Burgess Shale

  title={Hooking some stem‐group “worms”: fossil lophotrochozoans in the Burgess Shale},
  author={Nicholas J.F. Butterfield},
  • N. Butterfield
  • Published 1 December 2006
  • Biology, Environmental Science, Geography
  • BioEssays
The fossil record plays a key role in reconstructing deep evolutionary relationships through its documentation of the early diverging stem groups leading to extant phyla. In the middle Cambrian Burgess Shale, two famously problematic worms, Odontogriphus and Wiwaxia, have recently been reinterpreted as stem‐group molluscs based on their shared expression of a putative radula and putative ctenidia in Odontogriphus. 1 More detailed analysis of these fossil structures, however, reveals pronounced… 
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