Chimps are brutal, and it is so deliberate. The males go out and get near the boundary of their territory. And they walk very silently trying hard not to make any noise. They will climb into a tree and stare out over hostile territory for hours. They are waiting for the right opportunity. And then they attack.

Chimpanzees can be quite political.

I see that within each human being there are two extremes: there's the loving, the passionate, altruistic side that has evolved with us, and then there's the violent, brutal side that has evolved with us. The question for each individual is: which side is going to come out on top?

I sometimes wonder how some people can live with themselves in some of the big companies today. So many far-reaching decisions are based on how they will affect the next shareholders' meeting.

It's not that humans and non-humans are identical... but the lack of understanding that led to the slave trade is the same lack of understanding many people have about animals today. When slaves were brought over from Africa, many people believed they were not humans, that they didn't have feelings. Many people believe that primates and other animals don't have feelings, too, but they do.

When you meet these outstanding leaders who have been through a programme that empowers them to take positive action, to make things better for people, for animals and for the environment - when you watch them interact and they start brainstorming, you realise you can relax, because they have got it right. They understand that there's more to this life than just money.

Especially females and the younger ones like to be with somebody who is wise.