There are plenty of publicly-funded organizations and nonprofits that are trying to develop GMO crops that could help feed people in developing nations by producing disease-resistant or drought-resistant strains of staple crops like cassava or bananas.

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.

Part of what I wanted to do in my book was point out that we have almost reached the point where we can prevent a mass extinction with the science and technology we have today. We can build carbon neutral cities.

The early Triassic was a period when the planet was recovering from the worst mass extinction it had ever known - that was the end Permian extinction, where climate change caused in part by mega-volcanic eruptions wiped out ninety-five percent of life on Earth. It took about ten or twenty million years for the planet's ecosystems to stabilize. During that time you saw a lot of weird, out-of-balance ecosystems where, for example, crocodile-like predators ripped the crap out of each other along the coasts.

Humans are a great survivor species but our survival will be pretty grim if all of the plants and animals we depend on die out. That's why any human survival strategy has to include a plan to maintain our environment roughly in the state that it's in now.

Survivor species tend to have huge populations, so they can afford to lose many individuals and still survive as a species. They also tend to be small. If you're small, you need less food - which is great in a situation where famine is everywhere.

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.