I turned 65 last year, and each year I get more and more interested in human health. For most people it happens around age 50, but I've always been a slow learner. It's critical in terms of the cost of health care.

I've had a very unusual background in science - not the usual route of planning on being a scientist from age 3. I think my story shows that success is more about personal motivation and determination than it is about where you were born or what your economic status was.

In the past, geneticists have looked at so-called disease genes, but a lot of people have changes in their genes and don't get these diseases. There have to be other parts of physiology and genetics that compensate.

My early years were hardly a model of focus, discipline, and direction. No one who met me as a teenager could have imagined my going into research and making important discoveries. No one could have predicted the arc of my career.

We're still expecting capitalism to solve problems: 'Maybe if we sell enough oil, we can give some profits to an environmental agency!' Capitalism isn't a moral system.

I was so fanatical about trying to save wildlife... I was unable to accept that we couldn't solve this problem of thousands of years, of wherever humans operated, the environment deteriorated.

As populations continue to increase, and the climate continues to deteriorate, and as people flock in ever increasing numbers to large, underdeveloped cities, the threat of multiple protracted mega-emergencies has become reality.

The higher the stakes, the more responsible we have to be. It was with this in mind that I began to build my Green Economy and Climate Agenda.