People tend to focus on the here and now. The problem is that, once global warming is something that most people can feel in the course of their daily lives, it will be too late to prevent much larger, potentially catastrophic changes.

I traveled really to amazing places. I went to the Great Barrier Reef, I went to the Amazon, I went to the Andes, to try to bring people stories of sort of what's going on out in the world and bring this issue alive, in a way, and put it out there.

It may seem impossible to imagine that a technologically advanced society could choose, in essence, to destroy itself, but that is what we are now in the processnof doing.

Humans will eventually become extinct. People treat that as a radical thing to say. But the fossil record shows us that everything eventually becomes extinct.

Mitochondrial DNA, which is a sort of abridged version of DNA, is passed directly from mother to child, so it's something that can be looked at to trace matrilineal descent.

Humans will eventually become extinct. People treat that as a radical thing to say. But the fossil record shows us that everything eventually becomes extinct. It depends what "eventually" means. But the idea that were going to be around for the rest of global history...I don't think there's any scientist who would suggest that is true. It could be millions of years from now. We may leave descendants that are humanlike.

People sometimes say we need to be really almost on a wartime footing if you want to change. Our whole economy is based on burning fossil fuels, which is taking CO2 out of the ground and putting it up into the air.