Anyone who tries to improve the lives of animals invariably comes in for criticism from those who believe such efforts are misplaced in a world of suffering humanity.

What you do makes a difference, and you have to decide what kind of difference you want to make.

The tree I had in the garden as a child, my beech tree, I used to climb up there and spend hours. I took my homework up there, my books, I went up there if I was sad, and it just felt very good to be up there among the green leaves and the birds and the sky.

The chimpanzees taught me a lot about nonverbal communication. The big difference between them and us is that they don't have spoken language. Everything else is almost the same: Kissing, embracing, swaggering, shaking the fist.

Chimpanzees have given me so much. The long hours spent with them in the forest have enriched my life beyond measure. What I have learned from them has shaped my understanding of human behavior, of our place in nature.

Animals were my passion from even before I could speak apparently. When I was about 10, 11 I fell in love with Tarzan.

Chimps are very quick to have a sudden fight or aggressive episode, but they're equally as good at reconciliation.