The slime mold Dictyostelium discoideum spends much of its time as an apparently typical microscopic single-celled amoeba, oozing around in wet soil as it grazes on bacteria. Something truly odd happens, however, when the food runs out. Starving D. discoideum band together to form a conglomerate organism. A multicellular slug of sorts, the group grows into a spore-making tower, a beacon for sending amoebae out to richer grounds.