A eusocial insect (family Formicidae) belonging to the same order (Hymenoptera) as the bees and wasps, with a characteristic constriction (‘wasp-waist’) of the body segment separating the mesosoma (equivalent to the thorax) and metasoma (abdomen). Ants range in size from 0.75–52 mm, live in colonies, and occur worldwide except for Antarctica and some remote islands. Most are predators or scavengers, but some cultivate fungi and others tend aphids and feed on their sugary secretions. There are about 22,000 species.