One of the most amazing parts of writing this book was getting a chance to discuss the future of humanity with so many scientists, engineers, philosophers, historians, technicians, and sundry brainiacs. That over a hundred people would take the time to share their ideas with a stranger, about everything from geological history to space exploration, is testimony to the basic awesomeness of humanity.
Thanks to my fantastic agent, Laurie Fox, for making all of this happen, and to my benevolent editor, Gerald Howard. Thanks to Hannah Wood for tons of editorial help, and to artist Neil Webb (who created the gorgeous cover).
I could not have written this book if my boss, Nick Denton, hadn’t given me the time to do it—thanks, Nick! And thanks to the io9 crew for always inspiring me: Charlie Jane Anders, Cyriaque Lamar, Esther Inglis-Arkell, George Dvorsky, Lauren Davis, Meredith Woerner, Robbie Gonzalez, Rob Bricken, and Steph Fox.
Thanks to members of the unnamed writing group: Claire Light, Sacha Arnold, Nicole Gluckstern, Lee Konstantinou, and Naamen Tilahun.
Many friends and strangers read early versions of the manuscript and gave me feedback: Deb Chachra, Tom Levinson, Maggie Koerth-Baker, Ed Yong, Terry Johnson, Dave Goldberg, Matthew Clapham, Peter Eckersley, and Daniel Rokhsar. None of the factual errors in this book are their doing.
Most important, thanks to three wonderful hominins, Charlie, Chris, and Jesse, who put up with all kinds of nonsense while I was writing this book, and whose love makes me the luckiest person in this limb of the galaxy.