From this and previous research, it is clear that the evolution of fungus farming in these ants had as drastic an impact on ant life as the transition of humans from a nomadic, hunter- gatherer lifestyle to an agricultural one had on human life. The survey focused on gardens of the seven most evolutionarily primitive attine ants because those were the ants likely to be using the oldest, least evolved farming methods and fungi varieties. In much the same way researchers studying the history of human agriculture examine non-industrial agricultural societies like the indigenous farmers in New Guinea or Amazonia rather than wheat farmers in Kansas. Attine ants, who evolved the use of pesticides millions of years before humans, have developed herbicidal glands that produce antifungal secretions that are harmful to alien fungi but not to the symbiotic fungi the ants cultivate. Long before humans, ants also began to take steps to optimize growing conditions for their crops.
Ants grow their fungi in a compost or manure that is carefully prepared.
The ants then mix this vegetable matter with their own and other insects' feces to produce the manure in which the fungus grows. The fungus thus receives protection by the ants and a never-ending supply of carefully selected substrate brought in by the ant foragers. For their part in the symbiosis, the fungi convert plant matter into sugars and proteins that the ants consume. The fungi also detoxify ant food by degrading some of the insecticidal compounds produced by many plants. For attine ants, the switch 50 million years ago from a predatory to agrarian lifestyle opened up a novel food resource, just as it would for humans millions of years later.