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.

I'm really worried about what the world is going to be like when my daughters are young women, [when] they are young leaders or mothers or businesspeople - whatever they're going to be. I'm afraid they're going to have a less healthy and less biologically rich planet.

I'm glad I'm inspiring somebody.

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.

What drives me is that moment of discovery. I love the unknown.

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

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.

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

Today, I’m a conservationist because I believe that my species doesn’t have the right or option to determine the fate of other species, even ones that inspire fear in us.

Whether it's exploring the woods around where I grew up, or even today exploring the coastal habitats and environments where I live in New England, or in a remote wilderness we're featuring in one of my series - I love to be in the field and I love to explore.

I am really sobered by what's happening to ecosystems around our planet and to the wildlife that is to be found there.

Today, I’m a conservationist because I believe that my species doesn’t have the right or option to determine the fate of other species, even ones that inspire fear in us.

I'm a biologist. At my core, I'm a naturalist.

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.

I am really inspired when I am in an experience, at the front lines of conservation, and I see someone - a woman, a man, a child, a person - who has given up an opportunity to have a family, an opportunity for financial riches, even an opportunity for security, [to] put their whole life on the line to protect a species.

It's the best - combining the mediums of television, documentary, and books, to give you this transmedia experience for kids, for families, and for teachers.

We know that when push comes to shove, [we can] drive ourselves to save our planet.