I suppose happiness is something one enjoys, but I suspect that happiness is not a state but rather a transition.

It's coming home to roost over the next 50 years or so. It's not just climate change; it's sheer space, places to grow food for this enormous horde. Either we limit our population growth or the natural world will do it for us, and the natural world is doing it for us right now.

What I am interested in with birds, just as I am with spiders or monkeys, is what they do and why they do it.

I don't run a car, have never run a car. I could say that this is because I have this extremely tender environmentalist conscience, but the fact is I hate driving.

The World is full of wonders, but they become more Wonderful, not less Wonderful when Science looks at them.

I've been to Nepal, but I'd like to go to Tibet. It must be a wonderful place to go. I don't think there's anything there, but it would be a nice place to visit.

[W]hen we look at the graphs of rising ocean temperatures, rising carbon dioxide in the atmosphere and so on, we know that they are climbing far more steeply than can be accounted for by the natural oscillation of the weather ... What people (must) do is to change their behavior and their attitudes ... If we do care about our grandchildren then we have to do something, and we have to demand that our governments do something.