In Fiji, ants have learned to grow plants to house their massive colonies (ArsTechnica)
High in the trees on the Fiji islands, ants in the species Philidris nagasau are doing something extraordinary. They've brought in seeds from several species of a large, lumpy fruit from a plant known as Squamellaria and carefully planted them in the nooks and crannies of the tree bark. Once the plant takes root in the tree and begins to grow, the ants climb inside its young stalks and fertilize it. But then the real action starts. As the fruit swells, the ants move inside, carving tunnels and rooms into the fleshy interior. When the colony expands, it may include dozens of these fruits, which look like strange tumors sprouting from tree branches. (...)