A single ant is almost helpless. An ant colony can act like one giant animal

No individual ant plans the colony's nest layout, food supply chains or defense, yet together thousands of ants reliably solve all three, through nothing more than simple local signals like pheromone trails. Biologists call this emergent intelligence a superorganism: a colony that behaves, as a whole, less like a crowd of individuals and more like a single organism with ants as its cells.

— Bert Hölldobler, E.O. Wilson, The Superorganism: The Beauty, Elegance, and Strangeness of Insect Societies — W.W. Norton, 2009
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