CRISES IN THE DEVONIAN HISTORY OF THE RUGOSE CORALS

Citation
Wa. Oliver et Aeh. Pedder, CRISES IN THE DEVONIAN HISTORY OF THE RUGOSE CORALS, Paleobiology, 20(2), 1994, pp. 178-190
Citations number
41
Categorie Soggetti
Paleontology
Journal title
ISSN journal
00948373
Volume
20
Issue
2
Year of publication
1994
Pages
178 - 190
Database
ISI
SICI code
0094-8373(1994)20:2<178:CITDHO>2.0.ZU;2-G
Abstract
Detailed analysis of the stratigraphic ranges of Devonian rugose coral genera within the Old World and Eastern Americas Realms gives new inf ormation on faunal extinctions and other bioevents in both rearms. Var ious origination and extinction metrics are calculated from tabulation s of occurrences in each stage. The most significant faunal changes we re near or at the ends of the Lochkovian and Frasnian stages. The form er marks the gradual transition from dominance by Silurian families an d genera to the characteristic Devonian coral assemblages; the latter marks the virtual extinction of the Devonian families and genera. Othe r coral events are related to the two major changes. The data provide new bases for comparing the histories of the two realms. Most of the e vents are recorded in both, giving support to previous suggestions tha t the causes were worldwide. The coral record shows an increase (proba bly episodic) in environmental deterioration persisting through the Mi ddle Devonian and culminating in extinction at the end of the Frasnian . Eustatic sea level fluctuations may have caused the precursor events and a bolide impact may have caused the end-Frasnian extinction.