Overall this is an interesting lecture from 2009 on the nature of life, death, extinction, and evolution. Fast forward to 38min and 15sec. This is presented to put our current global circumstance into true perspective.
The real meat is when Yale professor Stephen C. Sterns provides a breakdown of the extinction of the dinosaurs due to a 30km asteroid slamming into Earth at 100,000 mph about 64 million years ago.
Apparently it took 15-25 million years for Mother Earth to return to it's former glory after that calamity.
Unfortunately this is basically how long it is going to take Nature to replenish the planet with biodiversity after our current day man-made mass extinction. -- Collapsenet Staff