Amazing ant facts
May 15, 2012
  • /Crop Sciences

There are an estimated ten thousand trillion ants worldwide, and they weigh roughly the same as all of humanity, according to University of Illinois Extension horticulture specialist Ron Wolford.

"This is very impressive, considering that the average ant is about one-millionth the size of a human being," he said.

Myrmecology, which is the term for the study of ants, comes from the Greek words myrmex (ant) and logos (study). Myrmecologists have discovered many amazing things about ants.

Ants can be found all over the world, except in Antarctica, Greenland, and a few inhospitable or remote islands. They live 45 to 60 days. They are very social and live in structured communities, which may be located underground, above-ground in mounds, or even in trees.

Ants are divided into castes, or classes: workers, males, and queens. Some species, including army ants, some leaf cutter ants, and Messors (a species of harvester ants), also have soldier ants

Worker ants forage for food, care for the queen's offspring, work on the nest, protect the community, and perform many other duties. They are all wingless females and generally do not lay eggs.

Soldier ants defend the colony. Their heads are large and packed with muscle. Often, the normal-sized worker ants are the first to enter a battle, but then they call in their larger soldiers to help.

The function of the queen ants is to lay enough eggs to ensure the colony's survival. Queens are usually larger than workers and are instantly recognizable because they have larger thoraxes (the middle section of the ant's body) to support their wing muscles. The queen's abdomen is also larger to accommodate the advanced egg-producing organs. Male ants are quite often the smallest of the castes. They usually have only one role in life, which is to mate with a queen. Male ants are produced from unfertilized eggs laid by the queen. Their antennae are not jointed, as are those of the other castes, though they probably have the best eyesight of all castes.

Ants mate "on the wing." The large-winged queens and smaller-winged males take to the air, following thermal currents. They can mate in the air or on the ground. The male will die after a day or two; the queen may mate with several more males.

The queen then finds a nesting site. She uses her middle and hind legs to detach her two pairs of wings, which she discards because she will never fly again. If she neglects to remove her wings, they will break off or get chewed off by a worker ant. She then digs a small hole, climbs into it, and plugs up the entrance from the inside. Hidden from the world, she lays her eggs and spends the rest of her life in darkness.

Ants communicate using chemical signals (pheromones), taste, physical touch, and sometimes, the vibration of their bodies to send messages about food, enemies, and the nest. Scents can travel rapidly over distances, enabling ants to signal many others.

Ants sometimes use sound to communicate. If the nest caves in, the ants inside signal with a little squeak that they need to be dug up. Some ants can send out a squeaking or buzzing sound by rubbing segments of their bodies together.

When an ant finds a large piece of food, it returns to the nest to collect its fellow workers, leaving a trail of odors as landmarks to help it find its way back to the food. This odor also leaves a message, "follow me to food," for the other ants in the colony.

It is estimated that ants can carry 10 to 50 times their body weight. This is because their muscles are thicker relative to their body size than those of larger animals.

Humans have many different types of faces, but ant faces are even more diverse. The shape of an ant's head and mandibles (strong jaws) and the size of its eyes can reveal the diet and lifestyle of each ant species.

For example, the Trap-jaw ant has mandibles that slam shut when they touch a target. "The closing of these mandibles is one of the fastest movements in the animal kingdom -- up to 145 miles per hour!" said Wolford. "That is 2,300 times faster than the blink of a human eye."

"On a gardening-related note, you may have noticed that peonies attract a lot of ants," Wolford said. "That is most likely because the ants have found aphids that are producing honeydew (excrement) that the ants harvest for their nests. With peonies, the flower-bud scales secrete sap that is rich in carbohydrates and that the ants can use as a food source."

"It was once thought that ants were necessary for peony flowers to open," he continued. "However, research shows that this is not true. The flowers open without any ant activity."

For more information about ants, visit the University of Illinois Extension web site, All about Ants, Be transported into the fascinating life of ants in Farmers, Warriors, and Builders: The Hidden Life of Ants at the Museum of Science and Industry in Chicago through July 8 (