I had a wonderful teacher about animal behavior - my dog Rusty. He taught me that animals have personalities, minds, and feelings.

One thing I had learned from watching chimpanzees with their infants is that having a child should be fun.

I don't have any idea of who or what God is. But I do believe in some great spiritual power. I feel it particularly when I’m out in nature. It’s just something that's bigger and stronger than what I am or what anybody is. I feel it. And it's enough for me.

I was even accused of teaching the chimps how to fish for termites which I mean that would have been such a brilliant coup.

As a child, we couldn't afford holidays overseas, so instead I travelled through books. I was inspired by Dr Dolittle and Tarzan.

If you educate women, family size tends to go down.

It's been proven by quite a few studies that plants are good for our psychological development. If you green an area, the rate of crime goes down. Torture victims begin to recover when they spend time outside in a garden with flowers. So we need them, in some deep psychological sense, which I don't suppose anybody really understands yet.