When Will Wright was developing Spore, his much acclaimed computer game, he interviewed several life scientists. He asked them how nature had actually done what he was attempting to simulate in the game—which was, among other things, the development of the earliest stages of life and its evolution. (Some billboard advertisements for the game feature the slogan “Evolution Begins at Spore.com.”) Among the scientists Wright consulted were Michael Levine, a geneticist at the University of California, Berkeley; Neil H. Shubin, a paleontologist at the University of Chicago; and Hansell Stedman, a surgeon at the University of Pennsylvania School of Medicine.