Persuading the Body to Regenerate Its Limbs

Each year, researchers from around the world gather at Neural Information Processing Systems, an artificial-intelligence conference, to discuss automated translation software, self-driving cars, and abstract mathematical questions. It was odd, therefore, when Michael Levin, a developmental biologist at Tufts University, gave a presentation at the 2018 conference, which was held in Montreal. Fifty-one, with light-green eyes and a dark beard that lend him a mischievous air, Levin studies how bodies grow, heal, and, in some cases, regenerate. He waited onstage while one of Facebook's A.I. researchers introduced him, to a packed exhibition hall, as a specialist in "computation in the medium of living systems." Levin began his talk, and a drawing of a worm appeared on the screen behind him.