Termites farmed fungi long before humans did

Termites of the subfamily Macrotermitinae build fungus gardens in their nests. Workers gather dead plant material, break it up and pass it through their gut, creating a substrate for Termitomyces. The fungus breaks down the difficult components of plants, and the termites eat the enriched mycelium and the nodules it produces. Neither partner runs the farm alone: the colony supplies raw material and a stable microclimate, while the fungus carries out much of the chemical digestion.

The association is about thirty million years old. Fossil structures interpreted as fungus gardens show that this form of agriculture existed long before humans. Analyses of relationships point to an African origin for the symbiosis, after which the termites and their fungi spread to other tropical areas of the Old World. Successive generations of colonies either carry inoculum or acquire it from the environment, depending on the termite lineage.

Termitomyces can produce large fruiting bodies growing up above a mound. In many regions of Africa and Asia these are prized food gathered by people. Underground, however, the mycelium remains most important. The mound works as a ventilation system and a temperature buffer, which helps maintain the conditions both the insects and the fungal culture need.

Termites are not the only farmers. Leafcutter ants and ambrosia beetles independently developed their own systems of cultivation. They differ in host, substrate and the way cultures are transmitted, so this is not one invention inherited from a common ancestor. Comparing these arrangements shows that agriculture does not require human planning: it can arise gradually, as natural selection ties the success of two organisms ever more closely together. In a tropical ecosystem the scale matters for the cycling of matter too: colonies process enormous quantities of dead vegetation and change the properties of the soil around their mounds. A garden is therefore at once a source of food and an element of the local ecosystem.

What the evidence actually shows

The oldest direct record is not a preserved mushroom but nest architecture. In Tanzania’s Rukwa Rift Basin, researchers described Oligocene fossil termite nests containing chambers and structures corresponding to fungus combs. Geological dating places them at roughly 25 million years old, confirming that African Macrotermitinae practised fungiculture long before human agriculture. Modern colonies bring fragmented plant material into the nest, inoculate it with Termitomyces, and consume the processed substrate and fungal nodules. “Farming” is a useful functional analogy, not a claim of conscious planning. Fossils provide a minimum age for the behaviour; molecular analyses may place the origin of the symbiosis earlier. They also do not show that all termites cultivate fungi. Fungus farming belongs to a specialized African and Asian termite lineage, while most termite species rely on other combinations of gut microbes and diets.