The difference between humans and their closest relatives is partly a matter of taste. Yams, pumpkins, and squash are as bland as potatoes to our tongues today, but to a chimp and our ancestors, wild varieties were bitter and yucky. Now scientists have pinpointed some of the genetic changes that allowed our ancestors to diversify their palates, potentially allowing them to take better advantage of a wide range of foods—and conquer the world. As humans adapted to new habitats, they had to become open to new culinary experiences. They ate more starchy tuberous roots, learned to cook their meat and bitter root vegetables, and eventually domesticated plants and animals. Those dietary revolutions helped make us human, giving our bodies the extra calories that enlarged our brains, while allowing our guts, jaws, and teeth to shrink as we ate softer, more easily digestible food.