I think a major element of jetlag is psychological. Nobody ever tells me what time it is at home.

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 mean, it is an extraordinary thing that a large proportion of your country and my country, of the citizens, never see a wild creature from dawn 'til dusk, unless it's a pigeon, which isn't really wild, which might come and settle near them.

If I can bicycle, I bicycle.

I don't think we are going to become extinct. We're very clever and extremely resourceful - and we will find ways of preserving ourselves, of that I'm sure. But whether our lives will be as rich as they are now is another question.

Fundamentally not to waste energy. If we were all to reduce our demands for energy, it would make an enormous amount of difference.

I think a major element of jetlag is psychological. Nobody ever tells me what time it is at home.