"EVIDENCE FOR IMPACT-GENERATED EXTINCTIONS"
Over the past few decades scientists have learned that life on Earth nearly became extinct, not once, but several times. These abrupt extinction events may all be associated with an asteroid or cometary impact event like the one that wiped out the dinosaurs some 65 million years ago.
Dr. Becker's presentation
(PowerPoint - 9 MB) and accompanying video (Quicktime
- 3 MB) are available.
These are based on her article in the March, 2002, issue
of Scientific
American.