Extinction: end-Triassic mass extinction

One of the five greatest mass extinction events in Earth’s history occurred at the end of the Triassic, c. 200 million years ago. This event ultimately eliminated conodonts and nearly annihilated corals, sphinctozoan sponges and ammonoids. Other strongly affected marine taxa include brachiopods, bivalves, gastropods and foraminifers. On the land, there is evidence for a temporal disturbance of plant communities but only few plant taxa finally dis- appeared. Terrestrial vertebrates also suffered but timing and extent of this extinction remains equivocal. The cause of the end-Triassic mass extinction was probably linked to the contemporary activity of the Central Atlantic Magmatic Province, which heralded the breakup of the supercontinent Pangaea. Possible kill mechanisms associated with magmatic activity include sea-level changes, marina anoxia, climatic changes, release of toxic compounds and acidification of seawater. Remarkably, long-term effects on marine biota were rather different between ecological groups: a nearly instantaneous recovery of level-bottomcommunitiesis contrastedbythe virtual absence of reef systems for nearly 10 million years after the extinction event.