M y first encounter with a Galápagos tortoise came when the driver of my taxi from the airport attempted a risky overtaking maneuver into the path of an oncoming bus. On the island of Santa Cruz, which is bisected by a single highway, this is a favorite sport: The white Toyota HiLuxes that serve as taxis overtake tour buses, while tour buses overtake trucks. But this time, the driver quickly pulled back behind the slow-moving car ahead of us. “Tortoise,” she explained. And there it was—a great