Language allows us to talk about the past and plan the future. We can teach children about things that are not present. And above all, we can bring people with different backgrounds and different knowledge together to discuss our problems. This actually gives me hope. I still think we are smart enough to not destroy planet Earth, our only home.

It's not Africa that is destroying the African rainforest, it's selling concessions to timber companies that are not African, they are from the developed world - Japan, America, Germany, Britain.

Your life matters. You can't live through a day without making an impact on the world. And what's most important is to think about the impact of your actions on the world around you.

You're thinking about putting scientists into small cages and doing research on them. I wish it could happen sometimes.

I never wanted to give up. I thought I might have to. Especially at the beginning when chimpanzees had never seen a white person before.They gave one look at me and ran away! They were scared, but eventually I got their trust.

Just think of the trust that often exists in soldiers. Within their own unit, you could say they have to trust each other. A spirit of camaraderie builds up and, in the end, they will risk their lives for each other. They may even go so far as to dehumanise the other, enemy group - a mechanism you can also observe in chimps.

Young people, when informed and empowered, when they realize that what they do truly makes a difference, can indeed change the world.