Early Cambrian metazoans in fluvial environments, evidence of the non-marine Cambrian radiation

Abstract

Research Article| June 01, 2011 Early Cambrian metazoans in fluvial environments, evidence of the non-marine Cambrian radiation Martin J. Kennedy; Martin J. Kennedy * Department of Earth Science, University of California−Riverside, Riverside, California 92557, USA *Current address: School of Earth and Environmental Science, University of Adelaide, Adelaide, SA 5005, Australia. Search for other works by this author on: GSW Google Scholar Mary L. Droser Mary L. Droser Department of Earth Science, University of California−Riverside, Riverside, California 92557, USA Search for other works by this author on: GSW Google Scholar Geology (2011) 39 (6): 583–586. https://doi.org/10.1130/G32002.1 Article history received: 15 Dec 2010 rev-recd: 04 Feb 2011 accepted: 09 Feb 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 Martin J. Kennedy, Mary L. Droser; Early Cambrian metazoans in fluvial environments, evidence of the non-marine Cambrian radiation. Geology 2011;; 39 (6): 583–586. doi: https://doi.org/10.1130/G32002.1 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 Here we describe the oldest evidence of non-marine animals from the early Cambrian Wood Canyon Formation, California, evidence created by metazoans of a variety of sizes and behaviors. Millimeter-sized vertical trace fossils, including the U-shaped burrow Arenicolites and the vertical burrow Skolithos, as well as a centimeter-scale horizontal trace fossil, occur in conglomerate and gritty arkosic sandstone bed tops within fluvial channels. These fossils demonstrate that animals were dwelling in this habitat coincident with, or possibly predating, the first trilobites, and extend the freshwater record of animals back at least 80 m.y. The development of a functioning terrestrial ecosystem was concurrent with the early Cambrian marine radiation and suggests that freshwater environments were populated early by metazoans and that ecological opportunity likely played a determining role in metazoan exploitation of non-marine habitats versus commonly assumed influences from physiological or nonbiological barriers. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.