The most extraordinary thing about trying to piece together the missing links in the evolutionary story is that when you do find a missing link and put it in the story, you suddenly need all these other missing links to connect to the new discovery. The gaps and questions actually increase - it's extraordinary.

How could I look my grandchildren in the eye and say I knew what was happening to the world and did nothing.

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.

In the old days... it was a basic, cardinal fact that producers didn't have opinions. When I was producing natural history programmes, I didn't use them as vehicles for my own opinion. They were factual programmes.

I'd like to see the giant squid. Nobody has ever seen one. I could tell you people who have spent thousands and thousands of pounds trying to see giant squid. I mean, we know they exist because we have seen dead ones. But I have never seen a living one. Nor has anybody else.

One in eight plant species face extinction.

I often get letters, quite frequently, from people who say how they like the programmes a lot, but I never give credit to the almighty power that created nature.