There have been 5 major extinction events during the history of life on Earth.
{"Image DocumentName": "There have been 5 major extinction events during the history of life on Earth.", "Image ImageDescription": "Some 99.9% of all species that have ever lived on Earth are now extinct. The Cretaceous-Tertiary Extinction (65.5 MYA) is probably the most well known, as it killed off all non-avian dinosaurs. 75% of all species went extinct.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}