Origination, extinction, and mass depletions of marine diversity

From: Paleobiology | Date: October 1, 2004| Author: Knoll, Andrew H; Wang, Steve C; Bambach, Richard K | Copyright information

Abstract.-In post-Cambrian time, five events-the end-Ordovician, end-Frasnian in the Late Devonian, end-Permian, end-Triassic, and end-Cretaceous-are commonly grouped as the "big five" global intervals of mass extinction. Plotted by magnitude, extinction intensities for all Phanerozoic substages show a continuous distribution, with the five traditionally recognized mass extinctions located in the upper tail. Plotted by time, however, proportional extinctions clearly divide the Phanerozoic Eon...

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