Burgess Shale

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Burgess Shale An horizon from the Cambrian of British Columbia which has yielded an exceptionally preserved fauna. It was originally discovered by C. D. Walcott in 1909. Apparently, the fauna was deposited in deep water on or near a submarine fan. Many of the animals are Arthropoda, but other groups are also represented, some of them bizarre. Their identification has been aided by the discovery of other Cambrian faunas, especially those in China, Greenland, and Australia. Some forms, including Anomalocaris and Opabinia, form a metazoan group between the Onychophora and arthropods, but the fauna as a whole represents a rapid radiation and was probably a typical Cambrian fauna, unusual only in the preservation of soft-bodied forms.

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