Kiparaki Marianthi

729

Family: Formicidae

Order: Hymenoptera

Class: Hexapoda

The External and Internal Structure of Ants

Color: usually black, brown or rust in color, though there are yellow, purple, green and blue ants.

The ant body consists of head, thorax and abdomen.

Head :

• One pair of antennae: most important sense organ of the ant. Ants use their antenna not only to touch but also to smell, communicate and explore.
• Eyes are not so important. Some species are blind. Other has 2 well — developed compound eyes, along with 3 simple eyes(on top of the head)
• Ants also have a pair of large strong jaws.

Thorax:

• Ants have 6 legs. The legs are very strong. This is why the ant does not fall off when hanging upside down. The foreleg has a brush (arrow) on the forelimbs for cleaning purposes.
• Ants have 2 pairs of membranous wings. Wings are present only during the nuptial period of reproductive males and females.
• The outside of the body is covered with a hard armor, which is called the exoskeleton.

Abdomen:

• The abdomen is articulated to the thorax by means of an abdominal pedicel, or stalk..

• The abdomen contains 2 stomachs. One stomach holds the food for itself and second stomach is for food to be shared with other ants.
• In winter, the amount of fat is increased and the abdomen becomes hard and thick.

Ants have 4 distinct growing stages:

Egg, Larva, Pupa and the Adult.

• The queen lays the minute egg
• The eggs hatch in 2 to 6 weeks and develop into white larvae.
• Larvae become pupae, after feeding for a period of a few weeks to several months.
• In some species the pupa is naked, and in others it is covered with cocoons spun from a substance that they secrete at the end of larva stage.

• After pupal stage, during which no food is eaten, the insect enters the adult stage.
• The ant has attained its full size when it leaves the pupa stage.

Ants are generally omnivorous, eating both plant and animal matter.

Some species, however, eat only certain specialized foods.

Ants sometimes attack on a living insect. Ants cooperate to cary food together into the nest.

Most ants build some sort of nest and store food in it.

Ants live in organized groups or "colonies".

Ants are social animals.

Social means that they work together and help everyone in the colony. In order for the colony to run smoothly, different ants have different jobs.

Some ants are farmers, gardeners, engineers, construction workers, tunnel diggers, babysitters and soldiers.

Each ant colony has at least one or more queens.

An ant colony lives in a nest.

Different types of ants build different kinds of nests. The nests of many species of ants commonly consist of chambers excavated under stones or logs or underground.

There are rooms in the nest, which are used for the storage of the ant eggs, others for storing food. Tired ants have rooms for resting. Young ants live in some of the rooms.

One large chamber is just for the queen and her eggs.

Colony activity varies from a high degree of activity a certain times at the day (usually early morning and late afternoon) to lethargy at other times, as through midday or in the early hours before dawn.

Activity in temperate zone ants also varies seasonally , from a high level in midsummer to dormancy in winter

Ants like all social insects have some degree of polymorphism.

Castes: the different types of individuals in a colony.

Caste determination is a developmental phenomenon regulated by the presence or absence of certain substances provided in the immature stages by other member of the colony.

• Males are only produced when they are needed and the only time they are needed is when new queens are looking for mates.

• Males generally die after fertilizing the queens in the nuptial flight.

• The males compete for the females.

• Females may mate with more than one male during the nuptial flight but they never mate again after it.

• The job of the queen is to lay eggs that the worker ants look after.

• Workers are generally sterile females.
• The workers dig tunnels that connect the chambers.

• The adult workers fed,clean and attend the immature ants during development.
• Only the older ants hunt for food. Once they have found food and eaten it, they come back to the nest and share it.

• Soldiers are specialized workers, with enlarged jaws that do virtually nothing but crack the seeds for the other ants to eat.

Note: Some ants after finding food, in returning to the nest they release a track of chemical secretion that directs others to the food.