Mesozoic marine revolution

The Mesozoic marine revolution (MMR) refers to the increase in shell-crushing (durophagous) and boring predation in benthic organisms throughout the Mesozoic era (251 Mya to 66 Mya), along with bulldozing and sediment remodelling in marine habitats. The term was first coined by Geerat J. Vermeij, who based his work on that of Steven M. Stanley. While the MMR was initially restricted to the Cretaceous (145 Mya to 66 Mya), more recent studies have suggested that the beginning of this ecological/evolutionary arms race extends as far back as the Triassic, with the MMR now being considered to have started in the Anisian or the Aalenian. It is an important transition between the Palaeozoic evolutionary fauna and the Modern evolutionary fauna that occurred throughout the Mesozoic.

The Mesozoic marine revolution was not the first bout of increased predatory pressure; that occurred around the end of the Ordovician. There is some evidence of adaptation to durophagy during the Palaeozoic, particularly in crinoids.