Even though I now know that it's likely the Earth will suffer through mega-volcanoes or meteor strikes that could take out millions or billions of people, I feel less anxious about it because I actually understand what the threats are. There's nothing like researching something exhaustively to make it less terrifying.

Cities should function more like ecosystems, or even metabolisms. When we build, we should be thinking about how we can integrate into the ecosystems around us, but without sacrificing all the niceties of civilization like good restaurants, concert halls, and high-speed Internet access. I'm saying that partly tongue-in-cheek, but I'm also deadly serious. The future of technology is sustainable ecology.

think we're still stuck in that agricultural mindset, where we imagine that we can shape the Earth. Sure, we can do that. But the Earth has the power to shape us much more powerfully. To survive climate change, we'll have to realize how dependent we are on our ecosystems for our own survival.

That said, a lot of people buy products with "green" in the brand name, but make no attempt to understand what it would really take to live sustainably. I think one of the most pernicious examples of magical environmental thinking is the anti-GMO movement.

The fact is that humans have been shaping the genetics of what they eat for thousands of years. Genetic engineering simply speeds up the process that used to take generations. Preventing people from getting things like golden rice or disease-resistant cassava destroys human life, and does not spare the environment in any way.

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.

Obviously it depends on how you define a word like "evolution," because of course we have been evolving - both biologically and culturally - in relation to the natural world for hundreds of thousands of years.