Birds were flying from continent to continent long before we were. They reached the coldest place on Earth, Antarctica, long before we did. They can survive in the hottest of deserts. Some can remain on the wing for years at a time. They can girdle the globe. Now, we have taken over the earth and the sea and the sky, but with skill and care and knowledge, we can ensure that there is still a place on Earth for birds in all their beauty and variety - if we want to... And surely, we should.

I'm a humanist. I'm neither one side nor the other.

I just wish the world was twice as big and half of it was still unexplored.

Children start off reading in books about lions and giraffes and so on, but they also-if theyre lucky enough and have reasonable privileges of any human being-are able to go into a garden and turn over stone and see a worm and see a slug and see an ant.

All our environmental problems become easier to solve with fewer people and harder - and ultimately impossible to solve - with ever more people.

I'm not an animal lover if that means you think things are nice if you can pat them, but I am intoxicated by animals.

Human beings, because we're so clever, have removed every single one of those population limiting factors... So nothing controls our increase in numbers except our own wish. Since I first started making television programs, the population of the world has increased three times. That's an extraordinary notion. Can it increase four times? Can it increase five times? The Earth is a finite size. So a point will eventually come when we run out of food, when we run out of space and when we will have destroyed most of the natural world. So ought we to do something about it before that happens?