Mass Extinctions and Their Aftermath

Book excerpt: The first book to review all the evidence concerning both the dinosaur extinctions and all the other major extinctions - of plant, animal, terrestrial, and marine life - in the history of life. All the extinction mechanisms are critically assessed, including meteorite impact, anoxia, and volcanism. - ;Why do mass extinctions occur? The demise of the dinosaurs has been discussed exhaustively, but has never been out into the context of other extinction events. This is the first systematic review of the mass extinctions of all organisms, plant and animal, terrestrial and marine, that have occurred in the history of life. This includes the major crisis 250 million years ago which nearly wiped out all life on Earth. By examining current paleontological, geological, and sedimentological evidence of environmental changes, the cases for explanations based on climate change, marine regressions, asteroid or comet impact, anoxia, and volcanic eruptions are all critically evaluated. -