Leaf-cutter ants in the amazon bring their freshly cut leaves to their home beneath the soil. They pile the leaves and let them age. Over weeks, a specific species of fungi releases enzymes that degrade the complex carbohydrates in the leaves. It is only after the fungi have deconstructed these carbohydrates that the ants are able to enjoy their meal.
The relationship is not one-sided. The ants are a vector for a bacteria that releases antimicrobial compounds on the fungi, which keeps other pathogenic mold from growing on the ants’ crop (the beneficial fungi has developed a resistance to the these compounds).
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