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Ediacarans |
1 Department of Earth and Ocean Sciences, National University of Ireland, Galway, University Road, Galway, Ireland (e-mail: b.macgabhann1{at}nuigalway.ie)
2 Department of Earth and Ocean Sciences, National University of Ireland, Galway, University Road, Galway, Ireland
3 Department of Geology, Trinity College, University of Dublin, Dublin 2, Ireland
Sole markings from the Upper Cambrian Booley Bay Formation at Booley Bay, Co. Wexford, Ireland, previously described as the Ediacaran-type fossil Ediacaria booleyi appear to possess a number of morphological characteristics which are not consistent with assignment to the genus Ediacaria, nor any other known Ediacaran taxon. An inorganic origin for the structures has been proposed by several workers; we tentatively consider them to be at least in part organic, and are currently working to evaluate this hypothesis critically. If organic, the organisms must have had a density similar to that of the sediment in which they were emplaced, and to survive the transport process, they must have had a rigid integument. Neither of these properties appears to be consistent with an interpretation as an Ediacaran-type organism. We suggest here that the Booley Bay specimens should be removed from the genus Ediacaria. If Ediacaria booleyi is not related to known Ediacaran organisms, this would remove a key aspect of the argument against a mass extinction at the Precambrian/Cambrian boundary.
