Ants and Their Biology

No one wants to find ants inside their buildings, whether it is a home or a commercial property. To better understand why the ants are there and how you can get rid of them, you must first gain some basic understanding about the biology of this pest insect.

Social Insects
The biology of ants is very complex as well as varied based on the various species of ants. All types of ants, however, are similar in the fact that they are social insects. As such, they always live in colonies that include many sterile workers along with several (or just one) individual ants that can reproduce. The social structure of the ant colonies has all of the members of the colony work together to meet their common goals, such as finding food and caring for each other.

Varieties of Ants
To say there are many species of ants is an understatement as there are more than 12,000 different species of these critters. These can include slave-making ants, driver ants, leafcutter ants, army ants, weaver ants, and more. Some ants will form a mutualism with another plant or animal species. For example, some ants work with leaf-feeding insects to enjoy their carb-rich secretions. The plant-feeding insects get protection while the ants get energy and food.

Distribution of Ants
You can find ants on every single continent in the world, with the exception of Antarctica. Some experts estimate that ants account for around 10 percent of the total animal biological mass around the world. This figure gets even higher if you limit the scope to the Amazon rainforest, where they account for nearly a full third of animal biomass.

Comparing Species Size
To provide an idea of the differences in ant appearance across various species, consider the following typical lengths based on species:
• Argentine ants are usually 1/8 of an inch long.
• Carpenter ants tend to measure between ¼ and ½ inches.
• Odorous house ants tend to be about 1/8 of an inch long.
• Pavement ants are about 3/16 of an inch.
• Pharaoh ants are usually about 1/16 of an inch in length.
• Red imported fire ants are between 1/16 and 1/5 of an inch long.
• Southern fire ants are between 1/8 and ¼ of an inch in length.
• Thief ants are about 1/32 of an inch long.

Metamorphosis in Ants
Ants undergo full metamorphosis throughout their lives. This means that their life begins as an egg before they become larva, then pupa, and finally adults. There are three types of adult ants: males, queens, and workers. For most ant species, the process of becoming a worker ant from an egg will take between three and five weeks.

Biology of Specific Adult Ant Roles
Queen ants are the biggest individuals in a colony of ants. They are the only female ants that can reproduce and they do so by laying eggs. Queens will help the works feed as well as groom the ants in the larvae stage. Queens are also responsible for locating nesting sites. Some species of ants will have a single queen in each colony while others might have more than one. It is important to note that of the thousands of queens that tend to be produced, just a few will successfully find a new colony. Queen ants live the longest of all ant castes. Male ants do not have any involvement in the general activities of the colony. Their main role is to mate with the queens. In most cases, a male ant will typically die within the two weeks following its mating.

Finally, worker ants are the most numerous types of ants and they are all sterile females. There are some variations in worker ants based on the species of ant. Some, like fire and carpenter ants, for example, are polymorphic. This means that there are multiple different sizes of ants that workers, with the size of the worker ant correlating to the types of duties it has in the colony. Other types of ants will have a single size of adult, including with Argentine ants. For these ants, the responsibilities of the worker ants are determined by age. The younger workers will relay as well as store food. They also defend the colonies, build tunnels. These younger workers additionally take care of the larvae, including protection, grooming, feeding, and transportation. The older worker ants are mainly responsible for gathering the food.

Establishing Colonies
Most new ant colonies are formed when a new queen leaves her former colony. In this case, she will then mate with one of the male ants and find a good site for her new colony. When she arrives at the new colony site, she will drop her wings. She then excavates a new nest. At this point, she will cloister herself in the nest for at least several weeks, depending on how long it takes for the eggs in her to mature. She will then lay the eggs in the nest. At this point, the queen dedicates her time to caring for the new young ants. She almost never leaves the nest at this point. Once the first generation of ants is reared, the queen gets help feeding the colony and grooming her from worker ants. In certain ant species, including the pharaoh ant and Argentine ant, new colonies will arise via budding. In this situation, the queen will mate while still in the old nest. Instead of going to a new site by herself, some workers from the old colony will follow the new queen to her new nesting site. For ants that make new colonies in this way, the queens might not fly very well or they may not even have wings.

It is also possible for workers to create new colonies via budding either without or with a mature queen. In this case, they will take some of the immature ants in the existing colony to the new nest site. This includes carrying the pupae, larvae, and eggs. They then ensure that some of these immature ants are reared to become reproductive females and males. Most of the biggest pests in the ant world, including carpenter, pharaoh, and Argentine ants, tend to have more than one queen in their colonies. Pavement ants and others, however, just have one queen. Depending on the specific species of ants, a new colony will begin producing reproductive ants which leave to create new colonies in either a few years or after just one season.

Ideal Nesting Sites
The majority of ants prefer to nest in soil. Even so, some will also choose to nest in voids in walls or wood. The ideal space for a nesting colony will offer protection for the queen and her larvae. It will also be close to food and moisture. Common nesting locations that get in the way of humans include under wood decks, in piles of firewood, in tree stumps, along sidewalks, by plants that produce honeydew, by buildings with plants or moisture, by leaking plumbing, under homes, in wall voids, and under stones, mulch, or stumps. Depending on the ant species, the colony will either stay in one location for years on end or move. Those ants that move frequently tend to do so thanks to insecticide treatments, physical disturbances, temperature changes, and flooding.

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