Cambrian origin of all skeletalized metazoan phyla—Discovery of Earth's oldest bryozoans (Upper Cambrian, southern Mexico)
Abstract
Research Article| June 01, 2010 Cambrian origin of all skeletalized metazoan phyla—Discovery of Earth's oldest bryozoans (Upper Cambrian, southern Mexico) Ed Landing; Ed Landing * 1New York State Museum, 222 Madison Avenue, Albany, New York 12230, USA *E-mail: elanding@mail.nysed.gov. Search for other works by this author on: GSW Google Scholar Adam English; Adam English 2Chevron Gulf of Mexico Business Unit, 5750 Johnston Street, Lafayette, Louisiana 70503, USA Search for other works by this author on: GSW Google Scholar John D. Keppie John D. Keppie 3Instituto de Geologia, Universidad National Automona de Mexico, Ciudad Universitaria, 04510 Coyoacan, D.F., Mexico Search for other works by this author on: GSW Google Scholar Author and Article Information Ed Landing * 1New York State Museum, 222 Madison Avenue, Albany, New York 12230, USA Adam English 2Chevron Gulf of Mexico Business Unit, 5750 Johnston Street, Lafayette, Louisiana 70503, USA John D. Keppie 3Instituto de Geologia, Universidad National Automona de Mexico, Ciudad Universitaria, 04510 Coyoacan, D.F., Mexico *E-mail: elanding@mail.nysed.gov. Publisher: Geological Society of America Received: 18 Nov 2009 Revision Received: 16 Jan 2010 Accepted: 26 Jan 2010 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2010 Geological Society of America Geology (2010) 38 (6): 547–550. https://doi.org/10.1130/G30870.1 Article history Received: 18 Nov 2009 Revision Received: 16 Jan 2010 Accepted: 26 Jan 2010 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 Ed Landing, Adam English, John D. Keppie; Cambrian origin of all skeletalized metazoan phyla—Discovery of Earth's oldest bryozoans (Upper Cambrian, southern Mexico). Geology 2010;; 38 (6): 547–550. doi: https://doi.org/10.1130/G30870.1 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 Exquisite Pywackia baileyi Landing n. gen. and sp. specimens from the lower Tiñu Formation, southern Mexico, extend the bryozoan record into the Upper Cambrian. They are ∼8 m.y. older than the purported oldest bryozoans from South China, and show that all skeletalized metazoan phyla appeared in the Cambrian. The new form differs from similar, twig-like cryptostomes by its shallow autozooecia and an elongate axial zooid, which may be homologous to the stolon in nonmineralized ctenostomes. It may morphologically resemble mineralized stem group bryozoans that retained a stolon-like individual, although an ability to bud was acquired by the feeding individuals (autozooids). The latest Cambrian origin of bryozoans, several mollusk classes (polyplacophorans, cephalopods), and euconodonts was a major evolutionary development and can be considered the onset of the Ordovician radiation of more complex marine communities. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
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Bryozoa appear relatively late, in the uppermost Cambrian, at the onset of the Ordovician radiation.
“By contrast, Bryozoa certainly appear relatively late, in the uppermost Cambrian, at the onset of the Ordovician radiation (Landing, English & Keppie, 2010).”
From Chronology of early Cambrian biomineralization (2012) · cites this paper as Landing, English & Keppie, 2010
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- Authors
- Landing, E., English, A., & Keppie, J. D.
- Affiliations
- New York State Museum (US)
- Chevron (United States) (US)
- Instituto de Geología (MX)
- Corresponding author
- Landing, Ed
- Venue
- Geology
- Publisher
- Geological Society of America
- Published
- 2010-06
- Volume
- 38
- Issue
- 6
- Pages
- 547-550
- ISSN
- 0091-7613 (ISSN-L)
- 1943-2682
- OpenAlex
- W1989822374
- Cited by
- 67
- References
- 30
- Citations by year
- 2026: 2 · 2025: 1 · 2023: 6 · 2022: 1 · 2021: 4 · 2020: 4 · 2019: 4 · 2018: 2 · 2017: 2 · 2016: 3 · 2015: 6 · 2014: 4 · 2013: 9 · 2012: 6
- FWCI
- 6.32
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Geology (publishedVersion)
- Topics
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Stratigraphy of Fossils
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Evolutionary Biology
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Evolution and Paleontology Studies
- Keywords
- Bryozoa, Upper Cambrian, fossil bryozoans, early metazoan evolution, southern Mexico
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