Ants are insects. Their relatives are wasps. There are over 12,000 species of ant, so if they all look alike to you, they are not. You can tell an ant from another insect because the feelers (called antennae) that stick out from their heads and act to sense the environment, have elbow joints. They also have very thin waists.

Ants form some of the world's largest colonies of living things. Leafcutter ant colonies may, for example, contain 8 million ants.

Ant colonies are well organised, so that different types of ant do different jobs. Very few of the ant colony can breed. Most are sterile – and female. Most of these wingless females are the 'workers' of the colony. Others are 'soldiers. So if you look at a large soldier ant and think it must be male, then you are mistaken. In fact, the colony has relatively few males. They are known as drones, and just one or two female ants called queens, who do all of the egg laying.

Ants begin life as eggs. The egg hatches within the nest, and becomes a larva (a kind of caterpillar, plural larvae). These larvae cannot move, and have to be fed by worker ants. The ants do this by bringing back up liquid food and passing it to the larvae. When larvae are nearly fully grown they may also be fed pieces of prey, fungus and so on. After moulting and growing several times, the larva begins to change. This is called pupating. They then emerge as adult insects, just as butterflies emerge after being caterpillars.

Larvae and pupae need to be kept at an even temperature, and workers move them about in the nest to make sure of this.

A worker spends the first part of her life attending to the nest, and then becomes part of the army that goes out looking for food or defending the colony.

Queens can live for up to 30 years, and workers live from 1 to 3 years. Males, however, live for only a few weeks.

Ants are active all year long in the tropics, but, in cooler regions they go into something close to hibernation.

Ants can be found everywhere except Antarctica. The number of ants is phenomenal. In most places, about a fifth of the entire animal mass is made of ants. So they outnumber beetles, bears, deer and so on in terms of the weight of their bodies.

Ants are very highly organised, and there are so many of them that they can even change the environment they are living in. Many of them also have special relationships with other animals, for example ants and greenfly.

Ants defend themselves by using soldiers who have large jaws, and also by spraying formic acid at their enemies. So many ants can usually be called on when there is danger, that they simply overwhelm their opponents.