Leaf-cutter ants tend gardens of fungi that efficiently deconstruct plant biomass. This process converts lipids in the leaves into lipids the ants can use. Lipids in these gardens are an energy source, a component of cells, and a chemical for communication between organisms. A multi-institutional team studied the variation in lipid content at the top, middle, and bottom regions of these fungal gardens. The three regions correspond to different stages of leaf degradation. The team also analyzed the lipids in the leaves that ants feed to the gardens and in nutrient-rich swellings called gongylidia that the fungi produce, and the ants eat. Using advanced chromatography and mass spectrometry techniques, the team found that the leaves and fungal garden components were enriched with different lipids.