The planet needs trees. If there is indeed that carbon dioxide out there in the atmosphere, the only species on the planet that can actually trap it for us in a natural process of photosynthesis are the trees.

As a scientist I cannot say we don't want to hear anything about GMOs, because these are advances in science. But I think its also important, especially when you are dealing with food, to be cautious.

The people are learning that you cannot leave decisions only to leaders. Local groups have to create the political will for change, rather than waiting for others to do things for them. That is where positive, and sustainable, change begins.

Obviously the world is moving away from high carbon energy to low carbon energy, and eventually moving away toward renewable energy. So it is in the interest of Africa to move towards that, because that's where the world is moving.

Education, if it means anything, should not take people away from the land, but instill in them even more respect for it, because educated people are in a position to understand what is being lost. The future of the planet concerns all of us, and all of us should do what we can to protect it. As I told the foresters, and the women, you don't need a diploma to plant a tree.

There are certain areas where foreign investors can help the local people to generate wealth, and improve their quality of life. Some companies, for example, Del Monte, which produces pineapples in Kenya, pay a huge amount of taxes, I am sure, to the Kenyan government, and they do create jobs for thousands of locals.

Having studied biology really helped me a lot because I quickly understand how biological systems work, and how they fail, and the tragedy of when they fail, because we are dealing with life systems, and when we hear that a species has become extinct, or is threatened, you realize that this could mean that this species will disappear from the face of the earth forever! So that understanding really gives you energy to do something to save it.