Many of the medicines we use today, to fight everything from AIDS to cancer, originate as a toxin in an amphibian skin. When we lose these animals, we lose resources. We lose keystone species in the environments where they live.

The natural resources we've depended on, if the places where they exist are not stable, our own livelihood and our health is put at risk.

Running is my addiction. It's always present. I'm constantly thinking about my next run.

I think a human animal is far more wild and unpredictable and dangerous and destructive than any other animal.

Our health as a society, our robustness as a community, as a nation, as a people, is not only dependent upon fiscal stability, military might, political strength - it's also dependent on a healthy planet.

We live in a time where we have more extinction happening on our planet than since the dinosaurs were wiped out 50 million years ago.

We are not far away from the point of no return when it comes to life on earth, and we have some radical choices to make.