Burgess shale−type biotas were not entirely burrowed away

Abstract

Research Article| March 01, 2012 Burgess shale−type biotas were not entirely burrowed away Robert R. Gaines; Robert R. Gaines 1Geology Department, Pomona College, 185 E. Sixth Street, Claremont, California 91711, USA Search for other works by this author on: GSW Google Scholar Mary L. Droser; Mary L. Droser 2Department of Earth Sciences, University of California−Riverside, Riverside, California 92521, USA Search for other works by this author on: GSW Google Scholar Patrick J. Orr; Patrick J. Orr 3UCD School of Geological Sciences, University College Dublin, Dublin 4, Ireland Search for other works by this author on: GSW Google Scholar Daniel Garson; Daniel Garson 2Department of Earth Sciences, University of California−Riverside, Riverside, California 92521, USA Search for other works by this author on: GSW Google Scholar Emma Hammarlund; Emma Hammarlund 4Nordic Center for Earth Evolution, DK-5230 Odense M, Denmark5Department of Palaeozoology, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden Search for other works by this author on: GSW Google Scholar Changshi Qi; Changshi Qi 6Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China Search for other works by this author on: GSW Google Scholar Donald E. Canfield Donald E. Canfield 4Nordic Center for Earth Evolution, DK-5230 Odense M, Denmark Search for other works by this author on: GSW Google Scholar Author and Article Information Robert R. Gaines 1Geology Department, Pomona College, 185 E. Sixth Street, Claremont, California 91711, USA Mary L. Droser 2Department of Earth Sciences, University of California−Riverside, Riverside, California 92521, USA Patrick J. Orr 3UCD School of Geological Sciences, University College Dublin, Dublin 4, Ireland Daniel Garson 2Department of Earth Sciences, University of California−Riverside, Riverside, California 92521, USA Emma Hammarlund 4Nordic Center for Earth Evolution, DK-5230 Odense M, Denmark5Department of Palaeozoology, Swedish Museum of Natural History, SE-104 05 Stockholm, Sweden Changshi Qi 6Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China Donald E. Canfield 4Nordic Center for Earth Evolution, DK-5230 Odense M, Denmark Publisher: Geological Society of America Received: 14 Jun 2011 Revision Received: 24 Oct 2011 Accepted: 27 Oct 2011 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2012 Geological Society of America Geology (2012) 40 (3): 283–286. https://doi.org/10.1130/G32555.1 Article history Received: 14 Jun 2011 Revision Received: 24 Oct 2011 Accepted: 27 Oct 2011 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Robert R. Gaines, Mary L. Droser, Patrick J. Orr, Daniel Garson, Emma Hammarlund, Changshi Qi, Donald E. Canfield; Burgess shale−type biotas were not entirely burrowed away. Geology 2012;; 40 (3): 283–286. doi: https://doi.org/10.1130/G32555.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Burgess Shale−type biotas occur globally in the Cambrian record and offer unparalleled insight into the Cambrian explosion, the initial Phanerozoic radiation of the Metazoa. Deposits bearing exceptionally preserved soft-bodied fossils are unusually common in Cambrian strata; more than 40 are now known. The well-documented decline of soft-bodied preservation following the Middle Cambrian represents the closure of a taphonomic window that was only intermittently open in marine environments thereafter. The prevailing hypothesis for this secular shift in taphonomic conditions of outer shelf environments is that soft-bodied biotas were literally burrowed away from the fossil record by increasing infaunal activity in muddy substrate environments; this would have affected geochemical gradients and increased the efficiency of organic matter recycling in sediments. New and recently published data, however, suggest a more complex scenario. Ichnologic and microstratigraphic data from Burgess Shale−type deposits indicate that (1) bioturbation exerts a limiting effect on soft-bodied preservation; (2) the observed increase in the depth and extent of bioturbation following the Middle Cambrian would have restricted preservation of Burgess Shale−type biotas in a number of settings; but (3) increasing depth and extent of bioturbation would not have affected preservation in many other settings, including the most richly fossiliferous portions of the Chengjiang (China) deposit and the Greater Phyllopod Bed of the Burgess Shale (Canada). Therefore, increasing bioturbation cannot account for the apparent loss of this pathway from the fossil record, and requires that other circumstances, including, but not limited to, widespread benthic anoxia, facilitated widespread exceptional preservation in the Cambrian. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.