A Redescription of a Rare Chordate, Metaspriggina walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada

  title={A Redescription of a Rare Chordate, Metaspriggina walcotti Simonetta and Insom, from the Burgess Shale (Middle Cambrian), British Columbia, Canada},
  author={Simon Conway Morris},
  • S. Morris
  • Published 1 March 2008
  • Environmental Science, Geography
Until recently, our understanding of the earliest history of the fish has been fragmentary in terms of the fossil record and conjectural with respect to many details of phylogeny. Fortunately, significant new information has become available in recent years, most notably from the discoveries of at least three taxa of agnathan fish from the Lower Cambrian Chengjiang Lagerstatte of Yunnan, China (Shu et al., 1999, 2003; Shu, 2003; see also Hou et al., 2002; Hou et al., 2004, p. 192–193; Zhang and… 
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The preservation of soft parts in fossils is rare because fossilization usually occurs long after decay has destroyed soft tissues, a notable exception is the soft-bodied fauna from the Middle Cambrian Burgess Shale located near Field in southern British Columbia, where both completelysoft-bodied groups and the soft parts of creatures with resistant skeletons are beautifully preserved.