Ants, facts and information

Common Name:

Ants

Scientific Name:

Formicidae

Type:

Invertebrates

Diet:

Omnivore

Group Name:

Army, colony

Average Life Span:

Several weeks to several years

Size:

0.08 to 1 inches

Size relative to a paper clip:

What are ants?

Ants are common insects, but they have some unique capabilities—including their legendary communication skills that allow their colonies to function as superorganisms.

There are 20 quadrillion ants on Earth—that’s 2.5 million ants for every human. Known ant species (members of the family Formicidae) number over 12,000, and some experts estimate upwards of 20,000 exist. They can be found almost anywhere in the world, with the exception of Antarctica, Iceland, Greenland, and some island nations.

(How do ants make “milk”?)

Invasive ant species are becoming a problem, however, with research showing that over 500 species of ants were found in countries where they aren’t native, having hopped a ride with humans, or our cargo and goods. These alien ants can change the dynamics of an ecosystem, consume resources, and kill other organisms. This damage adds up: From 1930 to 2021, invasive ants caused an estimated $51 billion in economic losses.

Appearance

Ants range in size from the miniscule up to one inch long, and usually appear black, brown, red, or yellow.

Ants look much like termites, and the two are often confused. Ants can be identified by their elbowed antennae, and narrow "waist" between the abdomen and thorax. Some ants have wings, which are longer in the front and shorter by their hind legs. The presence of wings indicates an ant’s fertility—ants with wings are either queens or the drones whose job it is to mate with them.

Diet and behavior

Enthusiastically social insects, ants typically live in structured nest communities that may be located underground, in ground-level mounds, or in trees. Carpenter ants, which include more than a thousand species in the genus Camponotus, nest in wood and can be destructive to buildings. (Much like termites, which cause far more severe damage.) Some species, such as army ants, defy the norm and do not have permanent homes.

A single ant colony can contain hundreds of thousands of individual ants. Communities are headed by a queen or queens—some polygynous species can have as few as two or up to thousands of queens. Queens lay thousands of eggs to ensure the survival of the colony. In some species, male ants (known as drones) often have only one role—mating with the queen. They often die shortly after. Worker ants, the most visible colony members, are females that never reproduce, but instead forage for food, care for the queen's offspring, work on the nest, and protect the community. Some workers can carry 50 times their own body weight. 

(Why invasive ants are a bigger threat than previously thought.)

Ants communicate and cooperate by secreting pheromones, or scent chemicals, that can alert others to danger or lead them to a promising food source. They typically eat nectar, seeds, fungus, or insects. However, some species have diets that are more unusual. Army ants, with their large mandibles and painful stings, may prey on reptiles, birds, or even small mammals.

Ant colonies are so tightly knit and efficient, they can pass useful knowledge between generations, which some experts believe constitutes a colony “memory.” This kind of communal knowledge is essential for defense, so ants can easily differentiate friendly and hostile forces.

Unusual ants

Within the many thousands of known ant species, there are many that fill unique ecological roles, resulting in the development of special physical characteristics and interesting behavior.

For example, ants have a variety of biological defenses. Fire ants bite and sting with a venom called solenopsin. They can also survive floods by clumping together to float on the water’s surface. Other species, like the newly discovered Pheidole drogon, have evolved to grow spikes or spines from their exoskeletons.

(How these ants help find fossils.)

One Amazon species (Allomerus decemarticulatus) cooperatively builds extensive traps from plant fiber. When an insect steps on one of the trap’s many holes, hundreds of ants inside use the openings to seize it with their jaws.

Another species, the yellow crazy ant (Anoplolepis gracilipes), is capable of forming so-called supercolonies that house hundreds or even thousands of queens. On Australia’s Christmas Island, the accidental introduction of yellow crazy ants in the early 20th century has led to a destructive infestation. The ants are a significant threat to the island’s endemic population of red crabs, displacing the crustaceans from their burrows or even killing them as they pass by ant nests during their annual migration from the forest to the coast.