Argentine ant

These ants are very small and brown.

They come from a place called Argentina. Now they live in many lands. They can even live in your home.

These ants like to find food. They like to find water too. They can live in cracks in walls.

Many ants live together in one big group. They do not fight their own kind. This helps them grow very large.

Sometimes they fight other ant groups. They fight for their space.

These ants are very good at living in new places.

Argentine ants are small, brown insects. They are only about 2.2 to 2.6 mm long.

These ants come from South America. They live in places like Argentina and Brazil. Now, they live on almost every continent. Humans helped move them to new lands.

Most ants fight other colonies. Argentine ants are different. They often live in giant groups called supercolonies. In these groups, ants from different nests do not fight. They act like one big family. One group in California may have nearly one trillion ants!

These ants can cause problems. They take over homes and farms. They can push out native ants. This hurts other animals. For example, lizards may lose their food. In South Africa, they may stop plants from growing by not moving seeds.

Argentine ants like to find food and water. They can live in the ground or in walls. If their nest gets too much water, they move to dry ground. They carry their babies to stay safe.

The Argentine ant is a tiny insect that has become a major traveler. These small, brown ants are only 2.2 to 2.6 mm long.

They are originally from South America. They live in places like Argentina, Uruguay, Paraguay, and Brazil. However, humans have helped them move all over the world. Now, they live on almost every continent except Antarctica. They thrive in areas with Mediterranean climates. This includes places like California, Japan, and Australia. Because they move so much, they are now considered one of the world's 100 worst invasive species.

Most ant species are very territorial and fight other colonies. Argentine ants work in a different way. In many new lands, they form what scientists call supercolonies. This happens because their genetic makeup is very similar.

Because they are so similar, ants from different nests do not attack each other. They can mingle and live together peacefully. One huge colony in California stretches from San Diego to near San Francisco. This single group may have nearly one trillion ants! They only fight when they meet a different supercolony. On those borders, millions of ants may die in constant battles.

Scientists have studied these ants for a long time to understand them. An Austrian scientist named Gustav L. Mayr first identified them in 1866. He found the first specimens near Buenos Aires, Argentina. Over the years, their scientific name has changed. They were once called *Hypoclinea humilis* and *Iridomyrmex humilis*. Eventually, they were moved to the name *Linepithema humile*. In 1913, researchers Newell and Barber reported that these ants do not show aggression between separate colonies. This was a big discovery about how they live together.

These ants can change how nature works in a new area. They often push out native ants that lived there first.

This can hurt other animals that rely on those native ants. For example, some lizards in California have declined because their food source is gone. In South Africa, these ants can even affect how plants grow. They do not move seeds underground like some other ants do. This means the seeds stay on the surface and may not grow. They also protect tiny pests like aphids to get sweet food called honeydew.

Argentine ants are also common pests in our homes and farms. They look for food and water in kitchens or cracks in walls.

If their nests in the ground get flooded, they will move to dry ground. They are very good at carrying their babies to safety. Because they have many queens, they are hard to stop with sprays. Instead, people often use slow-acting poison baits. These baits are carried back to the nest by workers. This eventually reaches the queens and the whole colony. Scientists are even finding ways to use the ants' own scents to control them.

The Argentine ant, known scientifically as Linepithema humile, is a small insect with a massive global impact. These ants are tiny, measuring only 2.2 to 2.6 mm in length. They are usually a dull light to dark brown color.

While they are native to the riparian floodplains of South America, they have become one of the world's 100 worst invasive species. Humans have accidentally moved them across the globe. They now thrive in Mediterranean climates on almost every continent except Antarctica. This includes places like Japan, Australia, Europe, and the continental United States.

In their native lands, Argentine ants live in small, territorial colonies. However, in the new areas where they have been introduced, they behave very differently. Because their genetic makeup is so uniform, ants from different nests often do not recognize each other as enemies. Instead of fighting, they form massive groups called supercolonies.

These supercolonies can stretch across hundreds or even thousands of kilometers. One famous example is the Very Large Colony in California. This single population stretches from San Diego to beyond San Francisco. It may contain nearly one trillion individual ants.

Conflict does still happen when different supercolonies meet. When the borders of two massive groups clash, the fighting is constant and violent. Unlike other ants that might fight for a few hours, Argentine ants clash ceaselessly. In San Diego, scientists mapped the boundaries where different supercolonies fight. On the border between the Very Large Colony and the Lake Hodges Colony, thirty million ants die every year. These battles occur on a battlefront that covers many miles. These fights can sometimes be stopped by heavy rain or adverse weather.

Scientists have worked to understand how these ants recognize their own kind. One interesting factor is the role of diet in their identity. Researchers found that ants incorporate hydrocarbons, which are oily chemical compounds, from their food into their cuticle, or outer shell.

Ants that eat the same things appear to recognize each other as kin. If two groups eat completely different foods, such as flies versus grasshoppers, they develop different chemical cues. These groups then react violently toward one another. This suggests that what an ant eats helps shape its social identity.

History shows how our understanding of this species has evolved. An Austrian entomologist named Gustav L. Mayr first identified these ants in 1866. He found the first specimens near Buenos Aires, Argentina. Originally, the species was named Hypoclinea humilis. It was later moved to the genus Iridomyrmex. Finally, in the early 1990s, it was placed in the genus Linepithema. In 1913, researchers Newell and Barber were the first to report that separate colonies of these ants showed no apparent antagonism toward each other.

Argentine ants can disrupt entire ecosystems when they arrive in a new place. They often displace native ants, which causes a chain reaction. For instance, in southern California, the decline of coastal horned lizards is tied to these ants. The lizards lose their food source when Argentine ants push out the native ants the lizards eat. In South Africa, these ants affect plant life. They do not take seeds underground like native ants do. This leaves seeds on the surface, where they may fail to germinate. They also protect pests like aphids and mealybugs to feed on honeydew. This protection can cause problems for farmers in agricultural areas.

In urban settings, Argentine ants are common household pests. They enter buildings looking for food or water. They are especially active during hot, dry weather. They also move into homes to escape flooded nests.

Because colonies have many queens, they are difficult to control with standard sprays. Spraying can actually cause queens to lay even more eggs. Instead, people use slow-acting poison baits. These baits are carried back to the nest by workers to reach the queens. Researchers are even studying ways to use synthetic pheromones or the ants' own scents to disrupt their trails or control their populations.