New report suggests Earth on the brink of a great extinction

Aired: 6/1/2014 | 0:03:41 | Clip
According to new research published in the journal Science this week, plant and animal extinctions are happening at a rate 1000 times greater than before humans walked the Earth. Stuart Pimm of Duke University joins Hari Sreenivasan to illuminate how extinction rates are determined and what can be done to help set conservation priorities.