One theory of the origins of agriculture holds that domesticated plants first emerged on dump heaps, where the discarded seeds of the wild plants that people gathered and ate—already unconsciously selected for sweetness or size or power—took root, flourished, and eventually hybridized. In time people gave the best of these hybrids a place in the garden, and there, together, the people and the plants embarked on a series of experiments in coevolution that would change them both forever.
