It has actually been suggested that warfare may have been the principle evolutionary pressure that created the huge gap between the human brain and that of our closest living relatives, the anthropoid apes. Whole groups of hominids with inferior brains could not win wars and were therefore exterminated.

Without the support of local people, you might as well give up because you can make all the noise you like, you can demarcate a national park, but if the people outside want to go creeping into a forest you really can't stop them. They've got to get a benefit.

When I was a child, the African forest sounded like a dream to me, because it was full of animals and it was wild.

There isn't a sharp line dividing humans from the rest of the animal kingdom. All the time, we find animals doing things that, in our arrogance, we thought were just human.

I am obstinate and I will not give in.

I just have this absolute belief that humans are moving away from cruelty and destruction towards a time when we can truly live in harmony with nature. When we understand that there is a spiritual power around us from which we can draw strength. That is where I believe human destiny ultimately is taking us. I just hope we have time.

The chimps' way of aggression is quick and brutal. I compare them to gang attacks.