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
Red harvester ant high availability of food and good foraging conditions, therefore a favorable cost-benefit ratio for the foragers exists. If the patroller return rate is too high, it may be a warning of danger, such as the sighting of a predatory lizard. A lower return rate could indicate lack of available food, or heavy competition Ant foraging is guided by chemical signals that lead the ants up to 50–60 m from the nest at times. Once an ant has decided to forage, it will almost always continue until it has found food to take back to the nest; 90% of returning foragers