According to scientists, an asteroid wiped out the last of the dinosaurs approximately 66 million years ago. This is just the most recent major extinction event our planet has experienced. There have been at least five, along with numerous minor events, and more could be on the way. The voices in this balanced anthology discuss whether claims of mass extinction can really be substantiated, the impact of these events, when another large-scale extinction may occur, and whether humans would survive a cataclysmic event designed to reboot the Earth.