Ants and their nests can be bizarre, frightening, and fascinating—all at the same time. These lairs, or colonies, are almost as varied as the thousands of ant species that live on earth. Ants may live in massive underground networks, huge aboveground mounds, rotting wood and, undoubtedly, in and around your home. Army ants are among the only ant species that do not build permanent nests. They create temporary shelters made entirely of ants with their legs linked. This type of nest is called, appropriately, a bivouac. Whatever the style, the nest acts as a fortress, shelter, storage facility and nursery.
Typical garden ants prefer soft, easy-to-excavate, soil under a rock, wall, or other protective feature. Some species build relatively simple nests with only a few galleries while others dig down more than 3 feet to create a complex maze of flat-floored chambers and interconnecting tunnels. Black garden ants also practice home invasion, overrunning nests built by other ant species which are better builders than they.
One of the biggest ant nests in the world was created in Europe by invasive Argentinian Argentine ants. The colony stretched for 3,750 miles and posed a major threat to local animals and crops. These invaders drive out native ants like the Formica rufa which build huge mounds from pine needles and other forest detritus. These nests are formed around rotting tree stumps. The mound-builders heap up piles of debris more than 3 feet high and 7 feet in circumference. The nests can also extend several feet below the surface.
Weaver ants are some of the most fascinating nest builders. Common in Africa and Asia, weaver ants create nests by sewing leaves together from a sticky secretion created by their larvae. The workers form a living chain to pull together the edges of two leaves and hold them in place. Other workers hold the larvae like a caulk gun, touching the head to the seams and pulling back. The silk emerges from the larvae and holds the leaves together. The process is repeated numerous times by thousands of ants until a ball of leaves all sewn together into a nest where the ants will live.