I think small animals can escape from many kinds of natural disaster more easily. There are just more places for them to hide, and more ways for them to find safe habitats. So this means that rats are set up to rule the Earth, but most of us already knew that. Now you know why.

I would want us to start our quest to survive mass extinction by rethinking how we build cities. Cities should be commonplaces of production, rather than consumption - they should be producing food, and fuel.

I disagree that we need to contemplate eliminating ourselves in order to move forward. Sure, I think a good dystopian story can serve to steer us on the right path toward a better world. But we also need stories that offer solutions to our problems that are realistic, and workable today.

To be fair, if we are having a mass extinction, we're in the early stages of it. I think it's knowing facts like that which has made me less fearful about the future. Mass extinction is a long, complicated process that we are just now beginning to understand - and likewise, we are just beginning to understand how we might prevent one.

GMO agriculture will probably save the world in this century. But in the developed world, where few people are haunted by the specter of famine, people are free to fetishize heirloom tomatoes and worry about the provenance of what sits on their dinner tables.

I try to be realistic and pragmatic. I have a lot of hope for humanity as a species, but obviously as individuals we can be extremely flawed. We may have to go through some very terrible times in the near future, even if we ultimately survive as Homo sapiens.

We have converted huge swaths of land and ocean into human habitats where we live and grow food and harvest energy. But there's been a sea change in the past century.