About
Range: All continents except Antarctica
Habitat: All land habitats Ants are everywhere!
You've seen them at picnics, wandering around your kitchen, and in the garden: ANTS! They seem to be everywhere—and we are lucky that they are. Ants are one of the most abundant animals on Earth, and their contributions to our ecosystems are important.
Ant basics
Ants are complex insects that live in large social groups called colonies. As insects, ants have a hard outer body called an exoskeleton and three body parts: head, thorax, and abdomen. Ants have two pairs of appendages on their head: the mandibles, used for grabbing or fighting, and maxillae, used for breaking up food into small bits for swallowing. Typically, ants have 2 compound eyes containing 6 to 1,000 lenses, though in some species the eyes are reduced or even non-functional. These eyes can only see objects close up but are very good at detecting motion. The head has antennae, which are used for touching, feeling, smelling, and tasting. Ants also use the antennae to communicate with one another and keep the colony running smoothly. An ant's six legs are attached to its thorax. Each leg has nine segments and two claws for gripping whatever the ant is climbing. The ant's abdomen holds the digestive organs, including the crop, which can be used to store food for the colony.
Hail to the queen!
Most ant colonies live in nests on or under the ground or in trees, but some ant species live in clusters, not building any nests at all. Most ant colonies have a queen, large numbers of female worker ants, and occasionally some males. The queen's only job is to lay eggs, and this she does throughout her entire life. But how does she begin her "reign"?
Beginning her "reign"
A young winged queen leaves her birth colony on her first and only flight with a number of winged males. Males are only produced for mating purposes and do no work other than to fertilize virgin queens. Mating flights typically include neighboring ant colonies, and the signals for this coordinated nuptial swarm are still not fully understood. After the queen and males mate, the males die. The young queen now finds a good site to make her nest and start her colony. She rakes the wings off her body, as she no longer needs them for her new life. The queen begins her new colony there, laying eggs and staying with the colony for the rest of her life. Some ant colonies do not have queens at all, and several species use a different strategy to start a new colony in addition to having a founding queen. In many primitive ant species, certain workers become egg layers and mate with males inside the nest to continue the colony after the queen dies. And many species of ants have several queens, either at the nest-founding stage or for the length of the colony's life.
Born to work
A queen ant lays thousands, sometimes millions, of eggs in her lifetime. Workers move each egg to a brood chamber in the nest, where they it hatches into larva and is fed until it turns into a pupa. The process that determines what kind of ant a young larva becomes is still not fully understood, but it is thought to be influenced by both workers and the queen and includes considerations like gender-based selective rearing and chemical signals. Talk about teamwork: ants really know how to work well together. Recent research has shown that ants in the nest change jobs regularly, and some spend a good deal of time doing nothing at all! The jobs within the colony are the same for all ant species. Workers must feed and care for the young and the all-important queen, provide food for the colony, defend their resources, and maintain the nest. Keeping the nest clean of waste and the bodies of dead members is important for the health of all.
Call out the cavalry
While all workers defend the nest as needed, many species have specialized workers called majors, also known as soldiers. These ants are larger than the other workers and have specialized mandibles for fighting, moving large objects, and crushing tough food items like seeds. However, it has been shown in some species that the kind of ant sent to defend the nest depends on the type of intruder. Invasions by other ant species of similar size bring the smaller workers running, but disturbances from larger animals call out the soldiers, which are better equipped to stab tender flesh and encourage the predator to look elsewhere for food!
