Agriculture clearly revolutionized human society, but the practice seems to have occurred on a simpler scale among a broad range of species. Termites, ants, fish, and snails all practice simple forms of "farming," in which a food source is organized and encouraged to proliferate in order to ensure a steady food supply. Today's issue of Nature identifies a similar case, this one involving a very unexpected species: the slime mold, which spends a big part of its life cycle operating as a single-celled amoeba.
One species of slime mold, Dictyostelium discoideum, has been used extensively for research, but no one had observed anything resembling farming within the lab populations. A team at Rice University, however, spotted it while working with samples freshly obtained from wild populations. At two sites, the farming strain was only about a third of the total population. So it's not clear whether this is a case of nobody having looked carefully or the lab strains not exhibiting any farming behavior.
