Louis [Leakey] was anxious to initiate a scientific study of these chimpanzees. It would be difficult, he emphasized, for nothing was known; there were no guidelines for such a field study; and the habitat was remote and rugged. Dangerous wild animals would be living there, and chimpanzees themselves were considered at least four times stronger than humans. I remember wondering what kind of scientist he would find for such a herculean task.

It may sound trite, but young people really are the future.

I would never say I was an icon, but so many people have said I am, so I suppose I am. I mean, I can't not be what everyone says I am. But I don't feel like an icon.

Hundreds and thousands of young people around the world can break through and can make this a better world for all living things. Once young people know the problems and are empowered to act, they have great power to impact the world.

Chimps are unbelievably like us - in biological, non-verbal ways. They can be loving and compassionate and yet they have a dark side... 98 per cent of our DNA is the same. The difference is that we have developed language - we can teach about things that aren't there, plan for the future, discuss, share ideas

You can't do everything. You can't do health and forestry and agriculture. You've got to focus and do one or the other.

I've got different ideas of complete happiness. But one is being by myself out in a forest, completely happy. Another is walking with a dog in some nice place. And three is sitting around preferably a fire, but not necessarily, and drinking red wine with friends and telling stories.