If my grandchildren were to look at me and say, 'You were aware species were disappearing and you did nothing, you said nothing', that I think is culpable. I don't know how much more they expect me to be doing, I'd better ask them.

I'm absolutely strict about it. When I land, I put my watch right, and I don't care what I feel like, I will go to bed at half past eleven. If that means going to bed early or late, that's what I live by. As soon as you get there, live by that time.

If you watch animals objectively for any length of time, you're driven to the conclusion that their main aim in life is to pass on their genes to the next generation.

If I can make programmes when I'm 95, that would be fine. But I would think I'll have had enough by then.

All our environmental problems become easier to solve with fewer people and harder - and ultimately impossible to solve - with ever more people.

We can now manipulate images to such an extrodinary extent that there's no lie you cannot tell.

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