I'm not a propagandist, I'm not a polemicist; my primary interest is just looking at and trying to understand how animals work.

The process of making natural history films is to try to prevent the animal knowing you are there, so you get glimpses of a non-human world, and that is a transporting thing.

It's like saying that two and two equals four, but if you wish to believe it, it could also be five ... Evolution is not a theory; it is a fact, every bit as much as the historical fact that William the Conqueror landed in 1066.

There are some four million different kinds of animals and plants in the world. Four million different solutions to the problems of staying alive.

Before the BBC, I joined the Navy in order to travel.

I can mention many moments that were unforgettable and revelatory. But the most single revelatory three minutes was the first time I put on scuba gear and dived on a coral reef. It's just the unbelievable fact that you can move in three dimensions.

I had a huge advantage when I started 50 years ago - my job was secure. I didn't have to promote myself. These days there's far more pressure to make a mark, so the temptation is to make adventure television or personality shows. I hope the more didactic approach won't be lost.