Ant

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Ants in amber

Scheme ant worker anatomy-en

Bullant head detail

Ant Head

Ants are a group of eusocial insects that belong to the family Formicidae within the order Hymenoptera, which also includes bees and wasps. Ants evolved from wasp-like ancestors in the Cretaceous period, around 140 million years ago, and have since diversified into a wide variety of species that are found on all continents except Antarctica. They are particularly prevalent in tropical forests, where they may constitute up to 25% of the terrestrial animal biomass.

Characteristics

Ants are easily identifiable by their elbowed antennae and a distinctive node-like structure that forms their slender waists. Adult ants typically fall into one of three roles within their highly organized social structure: queens, workers, or males. Queens are the reproductive females that establish new colonies and lay eggs; workers are non-reproductive females that gather food, care for the queen's offspring, and protect the community; males are winged ants whose primary role is to mate with the queen.

Behavior and Ecology

Ants exhibit complex behaviors and have the ability to organize vast colonies; some are known to consist of millions of individuals. Their social structure is based on an efficient division of labor and a sophisticated communication system that relies heavily on chemical signals known as pheromones. Ants are capable of finding food sources and communicating their location to other members of the colony, engaging in warfare with other colonies, and forming mutualistic relationships with other species, such as aphids and certain types of fungi.

Foraging and Food

Ants are omnivorous and have a diverse diet that includes nectar, fungi, seeds, and insects. Some species have specialized feeding habits, such as the leafcutter ants that cultivate fungus, which they feed on, by cutting and transporting leaves to their colonies.

Communication

Communication among ants is sophisticated and primarily chemical. Pheromones are used for a variety of purposes, including marking food trails, signaling alarm, and controlling reproduction. Physical communication, such as antennal contact and body language, also plays an important role in the social life of ants.

Reproduction and Life Cycle

The life cycle of ants begins with the mating flight, during which virgin queens mate with males and then land to start a new colony. After mating, males typically die, while fertilized queens shed their wings and seek a suitable nesting site. The queen lays her initial batch of eggs, which hatch into larvae that are entirely dependent on her for food. As these larvae develop into adult workers, they take over the duties of foraging, nest maintenance, and care of subsequent offspring produced by the queen.

Ant Societies

Ant societies are characterized by a high degree of cooperation and complex social organization. The colony, or nest, is the central unit of ant life, and activities are coordinated to support the survival and reproduction of the colony rather than individual ants. This eusocial behavior includes division of labor, cooperative care of the young, and, in some species, the presence of sterile castes.

Impact on the Environment and Humans

Ants play a vital role in the environment as predators of pests, dispersers of seeds, and aerators of the soil. However, some species are considered pests themselves, particularly when they invade homes in search of food or shelter. Notably, the red imported fire ant (Solenopsis invicta) and the Argentine ant (Linepithema humile) have been known to cause economic damage and ecological disruption in areas where they have been introduced.

Conservation

While ants are abundant and widespread, certain species are threatened by habitat loss and the use of pesticides. Conservation efforts are important to maintain biodiversity and the ecological roles ants play.