Colonization of the deep‐marine environment during the early Phanerozoic: the ichnofaunal record

摘要: Temporal changes in the ichnogeneric diversity and ethological structure of 50 Cambrian to Carboniferous deep-marine ichnofaunal assemblages were quantified. Assemblages age are distinctive: their is lower, pascichnia agrichnia relatively unimportant, ‘shallow-marine’ ichnotaxa more common, than subsequent periods. There appear be no environmental reasons that would have precluded extensive colonization environment during Cambrian. The significant restructuring communities at, or near, Cambrian–Ordovician boundary therefore attributed competition for ecospace and/or resources within shallow-marine environments early Phanerozoic, as a result which ichnotaxa, including examples agrichnia, displaced offshore. Nereites ichnofacies, traditionally understood, thus characteristic only younger Copyright © 2001 John Wiley & Sons, Ltd.