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Extinction and the fossil recordThe author examines evidence of mass extinctions in the fossil record and searches for reasons for such large extinctions. Five major mass extinctions eliminated at least 40 percent of animal genera in the oceans and from 65 to 95 percent of ocean species. Questions include the occurrence of gradual or catastrophic extinctions, causes, environment, the capacity of a perturbation to cause extinctions each time it happens, and the possibility and identification of complex events leading to a mass extinction.
Document ID
20040121557
Document Type
Reprint (Version printed in journal)
Authors
Sepkoski, J. J. Jr (University of Chicago Ill. 60637, United States)
Sepkoski JJ, ,. J. r.
Date Acquired
August 22, 2013
Publication Date
March 1, 1994
Publication Information
Publication: Geotimes
Volume: 39
Issue: 3
ISSN: 0016-8556
Subject Category
Geosciences (General)
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Exobiology
Non-NASA Center