These are some of the most common ants in Australia but are less common elsewhere.  They are found throughout Australia and can be very abundant, especially in urban areas such as yards, gardens and parks.  Some species, especially those found in forested areas, generally forage during the day while many of the arid zone species forage primarily in the evening and at night.  In forested areas they will forage on low vegetation and trees as well as on the ground.  They are general predators or scavengers, with some also taking honeydew and others showing a strong preference for seeds.  Workers generally forage singly or less often in small groups.  Some of the smaller species have a potent sting while others, including the larger species, have a weak sting or are unable to sting.
Nests are generally in soil either in the open or under rocks or other objects on the ground.  When in the open, nests range from low and messy mounds to large mounds decorated with stones and small twigs or leaves.  Species found in wet sclerophyll and rainforest often nest in rotten wood.  Some rainforest species will occasionally nest arboreally (although they nest on the ground as well).
Most species lack queens and instead have fertilised workers which produce brood.  In some, where true queens are present, the queens may be replaced by fertilised workers when they die.