We need to continue to decrease the growth rate of the global population; the planet can't support many more people.

In agriculture, people have taken wild plants that can't be eaten by people - and turned them into wonderful food sources. And that's because genomes can change, and people working with plants have picked mutations. Mutations are nothing more than genetic changes.

In many places in the developed world, we eat or waste probably twice as many food calories as we really need. We're wasteful of food. We ship all over the world. We're now realizing that generating the energy to ship the food around the world is also ruining our climate.

We've gotten so good at growing food that we've gone, in a few generations, from nearly half of Americans living on farms to 2 percent. We no longer think about how the wonderful things in the grocery store got there, and we'd like to go back to what we think is a more natural way.

If there are more and more environmental refugees, they are going to end up on your doorstep too.

In the last century, as we learned more about genes, we were able to devise ways of accelerating evolution.

We are sliding back into a dark era, and there seems little we can do about it. I am profoundly depressed at just how difficult it has become merely to get a realistic conversation started on issues such as climate change or genetically modified organisms.