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Specialized habitats

are like an extension of her body. Based on the

combined weight of their workers or the volume

of food they consume, ant colonies are some of

the largest predators on earth. Troops of workers

hunt other invertebrates and sometimes even

vertebrates: African driver ants can overcome big

animals such as dogs and goats that are caged or

tethered, and their marching columns are used by

African people to clear their homes or crop fields

of pests. These driver ants, and their South

American equivalents, the army ants, have no

fixed nest, but carry the queen and larvae with

them in ever-marching columns. Most other ants

have a vigorously defended nest, to which they

ANT NESTS AND COLONIES

Modern social ants arose from wasp-like ancestors

about 100 million years ago during the Cretaceous

period, when dinosaurs walked the earth. They

rose to ecological dominance, and still play a

major role as predators and scavengers in most

land ecosystems. An ant colony is a superorganism

controlled by a reproductive queen which

produces thousands of infertile workers that

forage and hunt for the colony, defend it, and rear

more workers. There is a view that an ant colony

is a single composite organism, because the queen

is the only individual capable of reproducing, and

the workers produced and controlled by the queen