Ant new estimates suggest that nearly 9% of all plant species may have such ant associations. Some plants in fire-prone grassland systems are particularly dependent on ants for their survival and dispersal as the seeds are transported to safety below the ground. Many ant-dispersed seeds have special external structures, elaiosomes, that are sought after by ants as food. A convergence, possibly a form of mimicry, is seen in the eggs of stick insects. They have an edible elaiosome-like structure and are taken into the ant nest where the young hatch. Most ants are predatory and some prey on and obtain food
Fire ant takes care of regular tasks (the main tasks in a colony are caring for the eggs/larvae/pupae, cleaning the nest, and foraging for food). However, "Solenopsis daguerrei" colonies contain no workers, as they are considered social parasites. Although most fire ant species do not bother people and are not invasive, "Solenopsis invicta", known in the United States as the red imported fire ant (or RIFA) is an invasive pest in many areas of the world, notably the United States, Australia, China and Taiwan. The RIFA was believed to have been accidentally introduced to these countries via shipping crates, particularly with Australia