Now, I find that very difficult to reconcile with notions about a merciful God.

It's a moral question about whether we have the right to exterminate species.

The process of making natural history films is to try to prevent the animal knowing you are there, so you get glimpses of a non-human world, and that is a transporting thing.

People talk about doom-laden scenarios happening in the future: they are happening in Africa now. You can see it perfectly clearly. Periodic famines are due to too many people living on land that can't sustain them.

Terrorism is an immediate problem that people are very concerned about, and I am as concerned about that as anyone else. But it isn't an either or situation.

Humanity is facing a very big, slow, long, drawn-out threat, and that is to do with the way the weather is changing and the size of the population.

Very few species have survived unchanged. There's one called lingula, which is a little shellfish, a little brachiopod about the size of my fingernail, that has survived for 500 million years, but it's survived by being unobtrusive and doing nothing, and you can't accuse human beings of that.