Phanerozoic shallow water diversity driven by changes in sea-level

Abstract

Shallow water (< 50 m) marine diversity curves for the Phanerozoic, based on area changes due to sea-level variation and continental movements, are presented. It is shown that a change in the degree of endemism can alter diversity more than the effect of sea-level change, or change in the number of faunal provinces. The pattern produced, for a constant degree of endemism, shows some rapid, but not periodic, falls in diversity. These occur in the Middle Cambrian, at the end of the Ordovician, Devonian, Permian, Cretaceous and Eocene, and in the Messinian. There is no recurring single cause for these falls.