I think that humans are also set up to survive. We're not as small as rats, but we make up for that by being intelligent enough to make our own hiding places and to adapt to new habitats, even if they are changing very quickly. We have an enormous population, and can afford to lose billions of people without suffering very much as a species. Indeed, some would say losing five billion people would be good for the planet - I disagree with them, but can't deny that we would do just fine if there were two billion of us or even one billion.

The fact that we have been able to perturb the carbon cycle with our industrial revolution is evidence of how vulnerable we are - because when we destroy our environments, we destroy our food and energy supplies. In short, we destroy ourselves.

So science alone cannot solve this problem [mass extinction of humans]. It's something that we can only tackle by bringing science together with culture, economics, and even politics.

Imagining the world without us is a recipe for despair and paralysis. I actually think it's more helpful to imagine the world before us, to look back at those unstable ecosystems of the Triassic and realize that were in another phase of unstable ecosystems. Knowing that, demystifying our situation as it were, makes it easier to think about solutions. We are not looking into the unknown. The only thing unknown about the situation is how we're going to fix it, and when.

A lot of environmental and biological science depends on technology to progress. Partly I'm talking about massive server farms that help people crunch genetic data - or atmospheric data. But I also mean the scientific collaborations that the Internet makes possible, where scientists in India and Africa can work with people in Europe and the Americas to come up with solutions to what are, after all, global problems.

I think it's the process of demystification, and realizing that we are not talking about some supernatural nightmare - we're talking about a natural process that the planet has gone through before, and which animals have survived before.

There are definitely recurring themes in humanity's relationship with our environment. The biggest is probably adaptation, because humans are incredibly good at adapting to new environments in relatively short periods of time. The ancestors of Homo sapiens started leaving Africa over one million years ago, moving from warm, tropical climates into the freezing wilderness of Europe and the desert ecosystems of the Middle East.