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.

All the modern devices we have enable us to investigate things and have enabled us to do better.

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

You've got to be fairly solemn [about the environment]. I mean the mere notion that there are three times as many people on Earth as there were when I started making television. How can the Earth accommodate them? When people, including politicians, set their faces against looking at the consequences-it's just unbelievable that anyone could ignore it.

An understanding of the natural world and what's in it is a source of not only a great curiosity but great fulfillment...

The reverse side of the coin in having this extraordinary ability to go anywhere, is that no one anywhere is remote any more.

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