Армейские муравьи: особенности поведения и роль в экосистеме.

Name used for several ant species

The name army ant (or legionary ant or marabunta) is applied to over 200 ant species in different lineages. Because of their aggressive predatory foraging groups, known as "raids", a huge number of ants forage simultaneously over a limited area.

The workers of army ants are usually blind or can have compound eyes that are reduced to a single lens. There are species of army ants where the worker caste may show polymorphism based on physical differences and job allocations; however, there are also species that show no polymorphism at all.

Colonies of real army ants always have only one queen, while some other ant species can have several queens. The queen is dichthadiigyne (a blind ant with large gaster) but may sometimes possess vestigial eyes. The stationary phase, which lasts about two to three weeks, begins when the larvae pupate. From this point on, the prey that were previously fed to the larvae are now fed exclusively to the queen.

The whole colony of army ants can consume up to 500,000 prey animals each day, so can have a significant influence on the population, diversity, and behaviour of their prey. While foraging, army ants cause many invertebrates to flee from their hiding places under leaves of the forest floor, under tree bark, and other such locations, thereby allowing predators to catch them more easily. For example, in the tropical rainforests of Panama, swarms of army ants attract many species of birds to this feast of scrambling insects, spiders, scorpions, worms, and other animals. Some of these birds are named "antbirds" due to this tendency. While focused on feeding on these invertebrates, birds at army ant swarms typically allow very close approach by peoplewithin in many casesoften providing the best opportunities to see many of these species. Depending on the size of the ant swarm and the amount of prey the ants stir up, birds can number from a few to dozens of individuals. Birds that frequent army ant swarms include the white whiskered puffbird, rufous motmot, rufous vented ground cuckoo, grey cowled wood rail, plain brown woodcreeper, northern barred woodcreeper, cocoa woodcreeper, black striped woodcreeper, fasciated antshrike, black crowned antshrike, spotted antbird, bicolored antbird, ocellated antbird, chestnut backed antbird, black faced antthrush, and gray headed tanager.

Army ants do not build a nest like most other ants. Instead, they build a living nest with their bodies, known as a bivouac. Bivouacs tend to be found in tree trunks or in burrows dug by the ants. The members of the bivouac hold onto each other's legs and so build a sort of ball, which may look unstructured to a layman's eyes, but is actually a well organized structure.