For most of this time life continued to flourish, but at and near the end of the period there were mass-extinction events that seriously affected planktonic forms like conodonts, graptolites, and some groups of trilobites (Agnostida and Pytchopariida, which completely died out, and the Asaphida which were much reduced). Brachiopods, bryozoans and echinoderms were also heavily affected, and the endoceridcephalopods died out completely, except for possible rare Silurian forms. The Ordovician-Silurian Extinction Events may have been caused by an ice age that occurred at the end of the Ordovician period as the end of the Late Ordovician was one of the coldest times in the last 600 million years of earth history.
Referencesedit
^Hambrey, M.J. (October 1985). "The late Ordovician—Early Silurian glacial period". Palaeogeography, Palaeoclimatology, Palaeoecology. 51 (1–4): 273–289. doi:10.1016/0031-0182(85)90089-6.
^Buggisch, Werner; Joachimski, Michael M.; Lehnert, Oliver; Bergström, Stig M.; Repetski, John E.; Webers, Gerald F. (2009). "Did intense volcanism trigger the first Late Ordovician icehouse?". Geology. 38 (4): 327–330. doi:10.1130/G30577.1. ISSN 1943-2682.
External linksedit
Middle & Late Ordovician Climate
The World during the Middle and Late Ordovician
The Late Ordovician
GeoWhen Database - Late Ordovician
The Ordovician Mass Extinction
BBC Evolution Weekend: Extinction Files (
February 16, 2024
late, ordovician, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, sources, news, newspapers, books, scholar, jstor, january, . This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Late Ordovician news newspapers books scholar JSTOR January 2024 Learn how and when to remove this template message The Late Ordovician also called the Upper Ordovician by geologists is the third epoch of the Ordovician period 1 At this time Western and Central Europe and North America collided to form Laurentia while glaciers built up in Gondwana which was positioned over the South Pole This caused a drop in global temperatures resulting in ice house conditions 2 For most of this time life continued to flourish but at and near the end of the period there were mass extinction events that seriously affected planktonic forms like conodonts graptolites and some groups of trilobites Agnostida and Pytchopariida which completely died out and the Asaphida which were much reduced Brachiopods bryozoans and echinoderms were also heavily affected and the endocerid cephalopods died out completely except for possible rare Silurian forms The Ordovician Silurian Extinction Events may have been caused by an ice age that occurred at the end of the Ordovician period as the end of the Late Ordovician was one of the coldest times in the last 600 million years of earth history References edit Hambrey M J October 1985 The late Ordovician Early Silurian glacial period Palaeogeography Palaeoclimatology Palaeoecology 51 1 4 273 289 doi 10 1016 0031 0182 85 90089 6 Buggisch Werner Joachimski Michael M Lehnert Oliver Bergstrom Stig M Repetski John E Webers Gerald F 2009 Did intense volcanism trigger the first Late Ordovician icehouse Geology 38 4 327 330 doi 10 1130 G30577 1 ISSN 1943 2682 External links editMiddle amp Late Ordovician Climate The World during the Middle and Late Ordovician The Late Ordovician GeoWhen Database Late Ordovician The Ordovician Mass Extinction BBC Evolution Weekend Extinction Files Retrieved from https en wikipedia org w index php title Late Ordovician amp oldid 1193205654, wikipedia, wiki, book, books, library,
