Amazon Ants - Slave Owners of the Wild

Ants have social parasitism, a phenomenon in which one species lives off another. Amazonian ants of the genus Polyergus raid other people's anthills, capture brood. These are future slaves who take full care of their masters. Polyergus does not have its own caste of working ants. They are not able to provide themselves with food, build a nest, take care of cocoons.

Gender Description

Amazonian ants (Polyergus) belong to the order Hymenoptera, family of ants, subfamily Formicina. The subfamily includes evolutionarily advanced species. The genus of Amazons is known for its "slaveholding" mode of existence. Its representatives are social parasites using the labor of other ants.

Insects are large enough, the covers of the body are dull, and the head is shiny. The main type of color is red-brown, there are types of red and black. The size of the soldier is 5.5-7 mm, the head is elongated, the chest is slender, the abdomen is pointed. The eyes are oval, there are eyes. The mandibles are thin and narrow. The lower jaw is reduced. The male is larger 6-7.5 mm. The head is wide, the abdomen is elongated, and the chest is short. The wings are transparent.

The female is distinguished by the largest size of all family members - 8-9.5 mm. The antennae, stings and paws are darker than the rest of the body. The wings are half darkened. In females and soldiers, the antennae consist of 12 segments, and in males, of 13. The smooth surface of the saber-shaped mandibles allows the invaders to deliver quick, precise strikes. In insects of the genus, the form of the mandible is with notches helping to retain food or larvae.

Distribution area

Amazon ants belong to the Holarctic group. Insects live in the Northern Hemisphere, their distribution zones are the northern part of Eurasia and America. Most of the species are found in the USA and Canada, 3 live in the countries of central and southern Europe. Representatives of three species live in Russia.

Lifestyle

How does the capture of another's nest and the transformation of ants into obedient slaves occur? An adult female of Amazons chooses a suitable anthill and kills the queen. In most cases, the colony takes it for its uterus. The female lays eggs, workers look after a brood of another species. Polyergus adults need periodic replenishment of slaves. New helpers get in the campaigns.

Soldiers conduct reconnaissance, find the nearest nest of representatives of the genus formika. Amazons line up in a column, reaching a length of 2 m, and a width of up to 25 cm. Their movement is clearly visible in the grass or on the steppe land. Soldiers swiftly attack the colony, grab larvae and eggs. Local ants do not immediately fight back, but after a few minutes they organize the evacuation of brood and engage in battle with the invaders. At this point, the main part of the Amazons with prey is heading to its nest. The remnants of the invaders are inferior in numbers to the enemy and die. After each campaign, the colony loses dozens of soldiers.

Interesting fact. Amazons use visual landmarks and chemical markers during raids.

The interaction of slaves and masters

In the process of evolution, the families of the genus Polyergus lost the caste of workers. They do not have ants capable of building nests for families, foraging, caring for offspring.They assign all these functions to the slaves that grew from the captured larvae. There is an exchange of information between insects. After several returns with prey, the workers begin to expand in advance the entrances to the anthill.

Slaves look after the brood: they feed the larvae, help the Amazons get out of the cocoon after the pupal phase is completed. They are engaged in the construction of nests. Hungry polyerhus touch the antennae with the front legs of the slaves, forcing them to feed. In the steppe, the main part of the dwelling is located underground, and a mound is built in the forest. The number of Amazons and slaves in one colony is approximately 1000 and 1500 individuals.

Information. The most commonly used slaves are brown forest and nimble steppe ants.

Kinds

There are 14 known species and subspecies. Among the most common:

• P. rufescens (yellow Amazon ant) ​​- the distribution area of ​​eastern and southern Europe, Western Siberia. Inhabit coniferous and deciduous forests, settle on the edges and clearings. The body of females and soldiers is yellowish red, covered with sparse black hairs. The size of females is 8–9 mm, males are 6–7 mm, and soldiers are 5–7 mm. Brown forest ants are abducted as labor. The species is listed in the Red Book of Belarus, the European Red List.
• P. topoffi - brown-red color, body length 5.5-6.6 mm. They live in the USA and Mexico. Raids are made in the evening, after a decrease in air temperature.
• P. breviceps is endemic to the United States. Adults are brown. In raids to capture slaves, soldiers and winged females participate. Insects are on the Red List of Threatened Species.
• P. samurai - distributed in China, Japan, Korea, the Far East. Females are black, workers are dark brown. Most nests have only one female.
• P. bicolor - differs from other Amazons in two-tone color and a small number of hairs. It lives in Canada.
• P. mexicanus is a typical area of ​​Mexico. Body color red, gray hairs. It inhabits open forests, meadows, found in the mountains.
• P. nigerrimus - the body of the workers is opaque, the females are shiny, the color is black. Found in Mongolia and southern Siberia - Buryatia, Tuva. The species is listed in the International Red Book.
• P. vinosus is a North American group found in coastal regions.
• P. lusidus are the red-brown Amazons of North America.
• P. oligergus - found in the southern United States (Florida). Females are red-brown, males are black.

The life of Amazon ants is completely dependent on the diligence of slaves, if they are deprived of helpers, insects will die of hunger. In the laboratory, experiments were conducted in which the Polyergus imago could not independently accept the food provided.