<P> Winged females and males leave their respective nests en masse and engage in a nuptial flight known as the revoada . Each female mates with multiple males to collect the 300 million sperm she needs to set up a colony . </P> <P> Once on the ground, the female loses her wings and searches for a suitable underground lair in which to found her colony . The success rate of these young queens is very low, and only 2.5% will go on to establish a long - lived colony . To start her own fungus garden, the queen stores bits of the parental fungus garden mycelium in her infrabuccal pocket, which is located within her oral cavity . </P> <P> In a mature leafcutter colony, ants are divided into castes, based mostly on size, that perform different functions . Acromyrmex and Atta exhibit a high degree of biological polymorphism, four castes being present in established colonies--minims, minors, mediae, and majors . Majors are also known as soldiers or dinergates . Atta ants are more polymorphic than Acromyrmex, meaning comparatively less difference occurs in size from the smallest to largest types of Acromymex . </P> <Ul> <Li> Minims are the smallest workers, and tend to the growing brood or care for the fungus gardens . Head width is less than 1 mm . </Li> <Li> Minors are slightly larger than minima workers, and are present in large numbers in and around foraging columns . These ants are the first line of defense and continuously patrol the surrounding terrain and vigorously attack any enemies that threaten the foraging lines . Head width is around 1.8--2.2 mm . </Li> <Li> Mediae are the generalized foragers, which cut leaves and bring the leaf fragments back to the nest . </Li> <Li> Majors, the largest worker ants, act as soldiers, defending the nest from intruders, although recent evidence indicates majors participate in other activities, such as clearing the main foraging trails of large debris and carrying bulky items back to the nest . The largest soldiers (Atta laevigata) may have total body lengths up to 16 mm and head widths of 7 mm . </Li> </Ul>

How do grass cutter ants access the nutrients of tough grasses growing in south america