The end and the beginning: recoveries from mass extinctions.

The evolutionary consequences of mass extinctions depend as much on the processes of survival and recovery following these biotic crises as on the patterns of extinction themselves. Paleontologists are currently documenting biotic recoveries from six major mass extinctions and several smaller biotic crises. Although the immediate responses are remarkably similar after each event, with low-diversity assemblages dominated by widespread, eurytopic species, the recovery response in the long-term is more varied. Lineages that survive the extinction can lack the resilience for recovery, whereas others vanish from the fossil record seemingly to return from the dead after several million years.