Trilobites in early Cambrian tidal flats and the landward expansion of the Cambrian explosion

Abstract

Research Article| February 01, 2014 Trilobites in early Cambrian tidal flats and the landward expansion of the Cambrian explosion M. Gabriela Mángano; M. Gabriela Mángano * 1Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada *E-mails: gabriela.mangano@usask.ca; luis.buatois@usask.ca; raastini@efn.uncor.edu; ARindsberg@uwa.edu. Search for other works by this author on: GSW Google Scholar Luis A. Buatois; Luis A. Buatois * 1Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada *E-mails: gabriela.mangano@usask.ca; luis.buatois@usask.ca; raastini@efn.uncor.edu; ARindsberg@uwa.edu. Search for other works by this author on: GSW Google Scholar Ricardo Astini; Ricardo Astini * 2Laboratorio de Análisis de Cuencas, Centro de Investigaciones en Ciencias de la Tierra, Universidad Nacional de Córdoba, Av. Velez Sarsfield 1611, X5016GCA Córdoba, Argentina *E-mails: gabriela.mangano@usask.ca; luis.buatois@usask.ca; raastini@efn.uncor.edu; ARindsberg@uwa.edu. Search for other works by this author on: GSW Google Scholar Andrew K. Rindsberg Andrew K. Rindsberg * 3Department of Biological and Environmental Sciences, Station 7, University of West Alabama, Livingston, Alabama 35470, USA *E-mails: gabriela.mangano@usask.ca; luis.buatois@usask.ca; raastini@efn.uncor.edu; ARindsberg@uwa.edu. Search for other works by this author on: GSW Google Scholar Author and Article Information M. Gabriela Mángano * 1Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada Luis A. Buatois * 1Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada Ricardo Astini * 2Laboratorio de Análisis de Cuencas, Centro de Investigaciones en Ciencias de la Tierra, Universidad Nacional de Córdoba, Av. Velez Sarsfield 1611, X5016GCA Córdoba, Argentina Andrew K. Rindsberg * 3Department of Biological and Environmental Sciences, Station 7, University of West Alabama, Livingston, Alabama 35470, USA *E-mails: gabriela.mangano@usask.ca; luis.buatois@usask.ca; raastini@efn.uncor.edu; ARindsberg@uwa.edu. Publisher: Geological Society of America Received: 29 Jul 2013 Revision Received: 29 Oct 2013 Accepted: 03 Nov 2013 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2014 Geological Society of America Geology (2014) 42 (2): 143–146. https://doi.org/10.1130/G34980.1 Article history Received: 29 Jul 2013 Revision Received: 29 Oct 2013 Accepted: 03 Nov 2013 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 M. Gabriela Mángano, Luis A. Buatois, Ricardo Astini, Andrew K. Rindsberg; Trilobites in early Cambrian tidal flats and the landward expansion of the Cambrian explosion. Geology 2014;; 42 (2): 143–146. doi: https://doi.org/10.1130/G34980.1 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 The timing of the early invasion of the continents, the routes to the land, and the environmental breadth of the Cambrian explosion are important topics because they are at the core of our understanding of early evolutionary breakthroughs. Illuminating some aspects of these problems are trilobite trace fossils in tidal-flat deposits from the lower Cambrian Rome Formation in the southern Appalachian Mountains of Tennessee (USA). Morphologic details and size range of the trace fossils suggest production by olenellid trilobites, which occur as body fossils in the same unit. The occurrence of this ichnofauna, together with physical structures indicative of periodic subaerial exposure (desiccation cracks) and deposition within the intertidal zone (flat-topped ripples), shows that trilobites forayed into the upper intertidal zone during the Cambrian. Our finding supports the migration of subtidal organisms into marginal-marine, intertidal settings at the dawn of the Phanerozoic, suggesting that trilobites contributed to the establishment of the intertidal ecosystem during the Cambrian. The sequence of events involved in the colonization of early Paleozoic tidal flats is consistent with the idea that most terrestrial taxa originated from marine rather than freshwater ancestors, and that direct routes to the land from marginal-marine ecosystems were involved in the colonization of continental environments early in the Phanerozoic. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.