Phanerozoic biodiversity: rocks or real?

Abstract

The marine biodiversity curve is an icon of paleobiology. The familiar curve shows increasing global diversity in the early Paleozoic, then a plateau, followed by increasing diversity through the Mesozoic and Cenozoic. The curve also gives us often quoted magnitudes of mass extinctions and the relay race of Evolutionary Faunas. When Sepkoski initially published his compilation, Raup, his colleague at the University of Chicago, questioned whether the curve represented a biological signal or was an artifact of the rock record. Raup's argument was compelling but his data modest, so the objection was tabled in the flush of new insight from Sepkoski's database.