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Ant is a Social Insect which is closely related to Wasps and Bees. Ants are one of the oldest kind of living creatures in the world. Ants today are not much different from Ants that lived 60 million years ago. Ants evolved from Wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. After the rise of flowering plants about 100 million years ago they diversified and assumed ecological dominance around 60 million years ago. They are the one of the topmost most successful of and numerous of all Insect Species. The reason behind their success is attributed to their social organisation and their ability to modify habitats, tap resources, and defend themselves.

Information on Ants

Ant Life Cycle
Types of Ants
Ant Anatomy
Ant Scientific Classification
Ant Behaviour
What Eats Ants?
Ant Habitat
Ant Reproduction
Ants and Society

Facts about Ants

Today, Ants thrive in most ecosystems and sometimes form 15–25% of the total population of organisms in a Forest. Their long co-evolution with other species has led to mimetic, commensal, parasitic, and mutualistic relationships. They are so numerous that, according to an estimate there are 22,000 Species, out of which more than 12,500 have been classified. They are easily identified by their Elbowed Antennae and a distinctive node-like structure that forms a Slender Waist.

The Life Cycle of the Ant has Four Stages. These are:

1. Egg - Ant Eggs are oval shaped and measure about 1 mm long. The Queen Ant cares for the first batch of Eggs, but once the new adults emerge, they take over nursery duties so the Queen can concentrate on laying more eggs.

2. Larva - Ant Larva look like worms. They have no legs, no eyes and rely on the Worker Ants in the colony to feed them. As they grow, they moult, shedding their skin to accommodate their increased size.

3. Pupa - A Pupa is the Cocoon Stage of the Ant. The Larva in some Species will spin webs around themselves within the colony nest in order to complete their transformation into adults. Other Ant Species have Pupa that are more like soft-bodied adults who simply need a short period of time inside the nest to form their hard outer body shell.

4. Adult - An Adult Ant appears in about six to 10 weeks after the Egg is laid. If the egg was Fertilized, the adult is a Female (diploid) and will join the colony as a Worker or Solider Ant. Unfertilized Eggs become Male Ants (haploid).

Most Ants live from 6 to 10 weeks, although certain Queens may live for as long as 15 years, and some Workers for up to 7 years.

Some Types of Ants

Army Ants - These travel in very large groups and eat any edible thing that comes in their path.

Carpenter Ants - These are known so because of their habit of making their nest in rotten wood. They consume the sweet juices from insects and plants.

Cornfield Ants - These eat the Honeydew that they milk from aphids.

Fire Ants - These can kill a small animal with their toxic sting.

Formica Ants - These suck on the juices from insects that they kill.

Harvester Ants - These usually eat seeds, but sometimes they eat insects too. They also store seeds to be eaten later.

Leaf Cutting Ants - These cut leaves to make underground gardens. Then they grow mushrooms in their gardens for food.

Odorous House Ant - These raise their abdomen in the air when disturbed and produce an odour when they are killed. This odour is similar to rotten coconut, giving them their odd name.

Thief Ants - These nest near and sometimes within the nests of other types of Ants, and steal both food and larva from them.

Weaver Ants - They make elaborate nests out of living tree-leaves.

Scientific Classification

Kingdom - Animalia.
Phylum - Arthropoda.
Class - Insecta.
Order - Hymenoptera.
Suborder - Apocrita.
Superfamily - Vespoidea.
Family - Formicidae.

Physical Features

Colour - Ants tend to come in dark or earth tones. Their colour is usually Yellow, Brown, Red, or Black. Different Species are Black, Earth-Tone Reds, Pale Tans, and Basic Browns. A Few Genera like Pheidole of North America have a Metallic Lustre.

Weight - Ant Weights differ from Species to Species. A 6 millimetres long Ant weighs about 3 milligrams (or 0.003 grams).

Size - Ants range in size from 0.75 to 52 millimetres (0.030–2.0 in)

Typically, an Ant has a Large Head and a Slender, Oval Abdomen joined to the Thorax, or Midsection, by a Small Waist.

In all Ants there are either One or Two Fin-like Extensions running across the Thin Waist Region.

Their Antennae are always Elbowed.

Ants don’t have ears. Ants "hear" by feeling vibrations in the ground through their feet.

There are Two Sets of Jaws: the Outer Pair is used for carrying and digging, and the Inner Pair is used for Chewing. Some Species have a Powerful Sting at the tip of the Abdomen.

Ants have Compound Eyes made from numerous Tiny Lenses attached together. They also have Three Small Ocelli (simple eyes) on the top of the head that detect light levels and polarization. Ants' Eyes are good for acute movement detection but do not give a high resolution.

Most Ants have poor-to-mediocre eyesight and a few Subterranean Species are completely Blind. However Australia's Bulldog Ant has exceptional vision.

Ants have an Exoskeleton, which is an external covering that provides a protective casing around the body and a point of attachment for muscles which is unlike Humans who have Internal Skeleton.

Ants do not have Lungs. Oxygen and other gases like Carbon Dioxide pass through their Exoskeleton through tiny valves called Spiracles.

Ants also lack closed blood vessels, instead, they have a long, thin, perforated tube along the top of the body, called the 'Dorsal Aorta' that functions like a Heart, and pumps Haemolymph towards the head, thus driving the circulation of the internal fluids.

The Nervous System consists of a Ventral Nerve Cord that runs the length of the body, with several Ganglia and Branches along the way reaching into the extremities of the Appendages.

All Six Legs of Ants are attached to the Mesosoma ("thorax"). They have a Hooked Claw at the end of each Leg which helps them climb and hang onto surfaces.

Most Queens and Male Ants have Wings. However, Queens shed the Wings after the Nuptial Flight, leaving Visible Stubs, a distinguishing feature of Queens. But there at the same time there are some species where Queen (ergatoids) and Males are Wingless.

The Metasoma i.e. the Abdomen of the Ant houses important Internal Organs, including those of the reproductive, respiratory (tracheae) and excretory systems. Workers of many Species have their egg-laying structures modified into Stings that are used for subduing prey and defending their nests.

Ants have special chemicals known as Pheromones, which are produced by a wide range of structures including Dufour's glands, poison glands and glands on the hindgut, pygidium, rectum, sternum and hind tibia.

Geographical Range and Habitat

Ants occur worldwide but are especially common in hot climates. They do not occur in Antarctica..

Behaviour

Ant Ranking / Castes- There are generally Three Castes, or Classes, within a colony:

1. Queen Ant - A Queen is generally the Largest Ant in the colony. She has wings until after her mating flight, when she removes them. The primary function of the Queen is reproduction, but after establishing a new nest she may also care for and feed the first brood of workers. Once she has produced her first brood, she becomes an "egg-laying machine," cleaned and fed by her offspring. She may live for many years until replaced by a Daughter Queen. Some Ant Species have more than one Queen in the nest.

2. Male Ant - Male Ants are generally winged and usually keep their wings until death. The Male Ant's only function is to mate with the Queen. After Mating the Male Ant dies, generally within two weeks. Males are produced in old, mature colonies.

3. Worker Ant - The Worker Ant is a Sterile, Wingless Female. They build and repair the nest, care for the brood, defend the nest, and feed both immature and adult Ants, including the Queen. There may be Specialised Workers and Soldiers of different sizes who specialize in certain tasks.

Ants communicate with each other using Pheromones (chemical secretion). Ants use the soil surface to leave Pheromone Trails which can be followed by other Ants. When a Foraging Ant find food it leaves a food trail on the way back to the colony; this trail is followed by other Ants, these Ants then reinforce the trail when they head back with food to the colony. When the food source is exhausted, no new trails are marked by returning Ants and the scent slowly dissipates.

Ants also use Pheromones as an alarm call. When an Ant is killed, it emits an Alarm Pheromone that sends nearby Ants into an attack frenzy and attracts more Ants from further away. In Ant Species with Queen Castes, Workers begin to raise new Queens in the colony when the Dominant Queen stops producing a specific Pheromone.

Ants attack and defend themselves by biting and, in many species, by stinging, often injecting or spraying chemicals like Formic Acid. This Acid causes mild to severe pain in other animals depending upon the Species.

Ants identify kin and nest-mates through their scent, which comes from Hydrocarbon-Laced Secretions that coat their Exoskeletons. If an Ant is separated from its original colony, it will eventually lose the colony scent. Any Ant that enters a colony without a matching scent will be attacked.

Ants form symbiotic associations with a range of Species, including other Ant Species, other insects, plants, and fungi. Aphids and other Hemipteran Insects secrete a sweet liquid called Honeydew when they feed on plant sap. The sugars in Honeydew are a high-energy food source, which many Ant species collect. In some cases the Aphids secrete the Honeydew in response to the Ants' tapping them with their Antennae. The Ants in turn keep predators away and will move the Aphids between feeding locations. On migrating to a new area, many colonies will take the Aphids with them, to ensure a continued supply of Honeydew.

Ants share their food by a Process named 'Trophallaxis', in which an Ant regurgitates Liquid Food held in its Crop, also known as 'Social Stomach'. The same process is also observed when Worker Ants provide food to the Larva.

The differentiation into Queens and Workers (which are both Female), and different Castes of Workers (when they exist), is determined by the Nutrition the Larva obtains.

Larva and Pupae require to be kept at fairly constant temperatures to ensure proper development, and as such are often moved around the various Brood Chambers within the colony.

In the tropics, Ants are active all year long but in cooler regions they survive the winter in a state of dormancy or inactivity. The forms of inactivity are varied and some temperate species have Larva going into the inactive state (diapause), while in others, the adults alone pass the winter in a state of reduced activity.

An Ant can lift 20 times its own body weight of their strong legs. It is also because strength is proportional to length squared (=surface area), and weight is proportional to length to the third power (=volume).

Ants use two most common methods of forming a new colony.

These are:

1. Budding - Budding is the breakaway of a group of Ants from a mature colony to form a new colony. The group usually consists of one or more Queens and some workers carrying Larva. Budding is common with species of Ants that have multiple Queens, such as Pharaoh Ants and Argentine Ants.

2. Swarming - Most Ants establish new colonies through swarming. Every now and then, particularly in spring or early summer, mature Ant colonies generate large numbers of winged forms. These are the young Queens and males, going off to mate. An inseminated Queen then rids herself of her wings and attempts to start a new nest in a cavity, under a stone or a piece of bark, or by excavating a hole in the ground. She rears her first brood alone, feeding them with salivary secretions and infertile eggs. If successful, the first brood opens up the nest and brings in food for themselves, the Queen, and subsequent broods, and the colony grows. However, the percentage of Queens that successfully begin new colonies is thought to be very small.

Ants are also known to keep Slaves of other Species of Ants. Ant colonies invaded by slave makers are quickly overcome and forced to support the slavemaking colony. Most commonly worker slavemaking Ants will raid a colony of another species of Ant, stealing eggs and bringing them back to their own nest.

Some Species raid the nest of other Ants and get rid of the Queens and replace her with one of their own. The new Queen mimics the old Queen by consuming pheromones from her body and releasing them to the attending Ants. This new Queen having mated with a Slavemaking male earlier begins to produce new slave makers.

In some species of Slavemaking Ants, the workers are strictly bred for the purpose of going out and conquering other nests. This colony cannot survive without slaves as the Slavemaking Ants lack the abilities to tend to the Queen, raise young and hunt for food.

Diet - The Diet of Ants consist of both Plant and Animals.

Certain Species, of the genus Formica, often eat the eggs and larva of other Ants or those of their own Species.

Some Ant Species consume the Liquid Secretions of Plants. The Genera - Leptothorax sips the Honeydew that has fallen onto the surface of a Leaf. Similarly the Argentine Ant and the Fire Ant also consume Honeydew.

The Honey Ants also obtain Honeydew from certain Aphids which actually is a by-product of digestion secreted by them. The Ant usually obtains the Liquid by gently stroking the Aphid’s abdomen with its Antennae.

Harvester Ants collect grass, seeds, or berries in the nest.

South America's Ants of the genus Trachymyrmex eats only Fungi which they cultivate in their nests.

Predators - Their Predators include Anteaters, Pangolin's, Spiders, Bears, Garden Lizard, Birds and several Marsupial species.

Reproduction

Most Ants are Univoltine, i.e. they produce a new generation each year. During the species specific breeding period, new reproductive, Winged Males and Females leave the colony in what is called a Nuptial Flight. Typically, the Males take flight before the Females. Males then use visual cues to find a common mating ground, for example, a landmark such as a pine tree to which other Males in the area converge. Males secrete a mating pheromone that Females follow. Females of some Species mate with just one Male, but in some others they may mate with anywhere from one to ten or more different Males. Mated Females then seek a suitable place to begin a colony. There, they break off their Wings and begin to lay and care for Eggs. The Females store the sperm they obtain during their Nuptial Flight to selectively fertilise future Eggs. The first Workers to hatch are weak and smaller than later Workers, but they begin to serve the colony immediately. They enlarge the nest, forage for food and care for the other Eggs. This is how new colonies start in most Species.

However there are Species where Females are capable of reproducing asexually through Thelytokous Parthenogenesis which means producing Females from unfertilized Eggs. There is one Species, Mycocepurus smithii which is a colony of All-Females.

In Folklore and Culture

In the Book of Proverbs in the Bible, Ants are held up as a good example for humans for their hard work and cooperation.

Aesop Fable 'The Ant and the Grasshopper' is also based on Ants hard work.

In the Quran, Sulayman is said to have heard and understood an Ant warning other Ants to return home to avoid being accidentally crushed by Sulayman and his marching army (Qur'an 27:18).

In parts of Africa, Ants are considered to be the messengers of the Gods.

Ant bites are often said to have curative properties. The sting of some species of Pseudomyrmex is claimed to give fever relief. Others use Ant bites in initiation ceremonies as a test of endurance.

Some Native American mythology, such as the Hopi mythology, considers Ants as the very first animals.

Mark Twain wrote about Ants in his 'A Tramp Abroad'. Some modern Authors have used the example of the Ants to comment on the relationship between society and the individual. Examples are Robert Frost in his poem 'Departmental' and T. H. White in his fantasy novel' The Once and Future King'.

From the late 1950s through the late 1970s, Ant farms were popular educational children's toys in the United States. Later versions use transparent gel instead of soil allowing greater visibility.

In some parts of the world (mainly Africa and South America), large Ants, especially army Ants, are used as surgical sutures. The wound is pressed together and Ants are applied along it. The Ant seizes the edges of the wound in its mandibles and locks in place. The body is then cut off and the head and mandibles remain in place to close the wound.

In South Africa, Ants are used to help harvest rooibos (Aspalathus linearis), which are small seeds used to make a herbal tea. The plant disperses its seeds widely, making manual collection difficult. Black Ants collect and store these and other seeds in their nest, where humans can gather them en masse. Up to half a pound (200 g) of seeds can be collected from one Ant-heap.

Ants and their larva are eaten in different parts of the world. The eggs of two species of Ants are the basis for the dish in Mexico known as 'Escamoles'. They are considered a form of insect caviar and can sell for as much as USD 40 per pound (USD 90/kg) because they are seasonal and hard to find.

In areas of India, and throughout Burma and Thailand, a paste of the green weaver Ant (Oecophylla smaragdina) is served as a condiment with curry.

The successful techniques used by Ant colonies have been studied in computer science and robotics to produce distributed and fault-tolerant systems for solving problems.