KNTV NBC Nightly News With Lester Holt December 1, 2015 01:48:00
Sixth massive extinction. >> it's the biggest loss since a comet hit the planet 65 million years ago and killed the dinosaurs. >> reporter: this time, it is not a comet, but a combination of things driving extinction. the carbon emissions the destruction of forests, and the overhunting. >> we are losing species between 100 and a thousand times faster than it should be. all accelerated because of one species. us. we are all trying to prevent life on the planet becoming another museum. >> i'm afraid we're sort of the asteroid right now. >> reporter: it is a dire prediction backed up by the world...