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.

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

The future of life on earth depends on our ability to take action. Many individuals are doing what they can, but real success can only come if there's a change in our societies and our economics and in our politics. I've been lucky in my lifetime to see some of the greatest spectacles that the natural world has to offer. Surely we have a responsibility to leave for future generations a planet that is healthy, inhabitable by all species

Climate change will affect the whole of humanity, while terrorist attacks will only affect a small section of humanity. Of course, you wouldn't say that if you were related to someone who had been beheaded or blown up or murdered. But 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.

The idea that the Lord had given us a present, that the world is a gift from God... well, the amount of stuff, back then, that the Lord was giving away was limited. We do not have dominion.

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.

Bringing nature into the classroom can kindle a fascination and passion for the diversity of life on earth and can motivate a sense of responsibility to safeguard it.