Lecture 21: Impacts and Extinction
We end our exploration of life on the Earth with a look at death in the\nfossil record. This lecture looks at the role asteroidal impacts have\nplayed in the history of the Earth, and their possible role in mass\nextinction events in the fossil record. We will discuss near-earth\nasteroids, historical impacts, and the K-T event in which a massive\nasteroid impact caused a mass extinction of species that included all\nnon-avian dinosaurs among its victims, opening up the biosphere to the\ndominance of mammals. We'll look at other mass extinctions during the\npast 500Myr, and talk about whether extinction-class impacts are in our\nfuture. Recorded live on 2009 Oct 22 in Room 1005 Smith Laboratory on\nthe Columbus campus of The Ohio State University.