Ant hills made by the yellow meadow ant, and the heaped leaf-litter nests of wood ants, always look impressive but pale into insignificance compared with the subterranean cities of exotic ant species.

In Central and South America, the interconnected labyrinth of brood chambers, fungus gardens (using those cut leaves as compost) storage silos and waste storage facilities of leafcutter ants can reach the size of a tennis court. Experiments in which latex or plaster is poured into these tunnels, then excavated, have revealed structures the size of camper vans, suggesting colony populations of six million ants.

However, the largest colonies may be those of the Argentine ant Linepithema humile, an invasive ‘tramp’ species native to South America. In North America, Japan, Australia, South Africa and Europe, where the species has been accidentally introduced, neighbouring colonies have mingled and united to form supercolonies.

One supercolony in Europe spans 6000 km of the coasts of Portugal, Spain, France and Italy and contains millions of interconnected nests and countless billions of happily cooperating sisters.

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Anthill in a coniferous forest © Getty Images