We tend to think of agriculture as a human innovation. But insects beat us to it by millions of years. Various ant species cooperate with fungi, creating a home for them, providing them with nutrients, and harvesting them as food. This reaches the peak of sophistication in the leafcutter ants, which cut foliage and return it to feed their fungi, which in turn form specialized growths that are harvested for food. But other ant species cooperate with fungi—in some cases strains of fungus that are also found growing in their environment.