A river of eggs flows along the elaborate conveyor system at Granja Mantiqueira, the largest egg farm in South America, where each day, some 5.4 million eggs travel from 8.4 million hens to egg crates without ever being touched by a human. Located in Primavera do Leste, Mato Grosso, Brazil, the highly automated facility increases efficiency and cuts costs, creating economies of scale that have dominated global agriculture since the Green Revolution of the 1960s. But the winds of change are now blowing in the other direction. The company is investing in a cage-free system that is certified humane, as well as organic eggs to meet a growing demand from consumers for better treatment of farm animals and fewer chemical inputs.