Ant colonies often appear as small mounds in a garden, but some species build structures of massive proportions. In South America, leafcutter ants construct underground labyrinths with chambers for fungus, waste, and brood. Researchers using liquid casts have mapped these nests to discover structures as large as camper vans, housing populations of six million insects.
These impressive structures are small compared to the global impact of the Argentine ant, Linepithema humile. Native to South America, this invasive species has spread across North America, Japan, Australia, South Africa, and Europe. Unlike typical ant populations that defend territory from neighbors, these ants unite to form supercolonies.
One such supercolony in Europe spans 6000 km along the coasts of Portugal, Spain, France, and Italy. This massive network contains millions of interconnected nests. Within this territory, billions of ants cooperate, acting as a single entity across international borders. These supercolonies represent a significant shift in insect behavior where invasive success relies on the elimination of traditional territorial competition.