ant
Insect belonging to the family Formicidae, and to the same order (Hymenoptera) as bees and wasps. Ants are characterized by a conspicuous waist and elbowed antennae. About 10,000 different species are known; all are social in habit, and all construct nests of various kinds. Ants are found in all parts of the world, except the polar regions. It is estimated that there are about 10 million billion ants.
Ant behaviour is complex, and serves the colony rather than the individual. Ants find their way by light patterns, gravity (special sense organs are located in the joints of their legs), and chemical trails between food areas and the nest.
Specialized roles
Communities include
workers, sterile, wingless females, often all alike, although in some species large-headed ‘soldiers’ are differentiated;
fertile females, fewer in number and usually winged; and
males, also winged and smaller than their consorts, with whom they leave the nest on a nuptial flight at certain times of the year. After aerial mating, the males die, and the fertilized queens lose their wings when they settle, laying eggs to found their own new colonies. The eggs hatch into wormlike larvae, which then pupate in silk cocoons before emerging as adults.
Remarkable species
Some species conduct warfare. Others are pastoralists, tending herds of
aphids and collecting a sweet secretion (‘honeydew’) from them. Army (South American) and driver (African) ants march nomadically in huge columns, devouring even tethered animals in their path. Leaf-cutter ants, genus
Atta, use pieces of leaf to grow edible fungus in underground ‘gardens’ which can be up to 5 m/16 ft deep and cover hundreds of square metres. Weaver ants, genus
Oecophylla, use their silk-producing larvae as living shuttles to bind the edges of leaves together to form the nest. Eurasian robber ants
Formica sanguinea raid the nests of another ant species,
Formica fusca, for pupae, then use the adults as ‘slaves’ when they hatch. Among honey ants, some workers serve as distended honey stores.
| The largest ant communities known have about 3 million members. One is in the Jura Mountains, eastern France, covering 7 sq km/2.7 sq mi and comprising 1,200 linked ant hills. |
