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

I've been bitten by a python. Not a very big one. I was being silly, saying: 'Oh, it's not poisonous' Then, wallop! But you have fear around animals.

Being in touch with the natural world is crucial.

Do we really require so many gardening programmes, makeover programmes or celebrity chefs?

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

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.

Getting to places like Bangkok or Singapore was a hell of a sweat. But when you got there it was the back of beyond. It was just a series of small tin sheds.