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 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.

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.

Nature isn't positive in that way. It doesn't aim itself at you. It's not being unkind to you.

Dealing with global warming doesn't mean we have all got to suddenly stop breathing. Dealing with global warming means that we have to stop waste, and if you travel for no reason whatsoever, that is a waste.

In the West, that's what's happening. The birth rate has been dropping steadily and still is. But there is still a vast amount of the world where that's not the case. And that is where the big population growth is taking place.

I've never actually met one in the wild, but I have seen a king cobra. They go towards people, they rear up six feet tall and they're very aggressive and they are very fast. And one bite means certain death. So if I encountered a king cobra in the wild I would be very alarmed.