434 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 60 



stroked by a hungry worker, they respond by regurgitating droplets 

 of their honeydew. It is not explained whether these "repletes," as 

 they are called, voluntarily offer themselves as colony food bags, or 

 get that way because of their greed for honeydew. 



As already noted, in any society there must be some bond that holds 

 the members together. With the ants as with the termites, the bond 

 appears to be mutual food exchange between individuals. The adult 

 ants exchange regurgitated food, and the young larvae may be fed 

 in the same manner, though most larvae can eat solid food. The 

 larvae themselves, however, produce exudates from the skin and 

 salivary secretion that appeal to their adult nurses, and are also much 

 in demand by the other workers and the queen. The larvae thus get 

 much attention from all members of the colony. The ants therefore 

 like one another in a very literal (gustatory) sense. Furthermore, 

 various other insects that have agreeable exudations to offer live as 

 welcome guests or as permanent residents in the ant nest. 



There are species of ants that have acquired the name of "slave- 

 makers," but they are really kidnapers, and as such they demand no 

 ransom. They raid the nests of some other species and carry off older 

 larvae and pupae to their own nest. When the adults of the captured 

 species emerge they at once assume the duties of workers, being en- 

 tirely unaware that they are in a strange nest, and the captors treat 

 them as members of their own species. The "slaves" therefore suffer 

 no more than a change of nests, and in some cases they become more 

 numerous than the nest owners. 



Then there are the so-called amazon ants, named not from the river 

 but from those famous female fighters of fiction. The females of the 

 species are amied with such long, sharp, curved mandibles that they 

 cannot construct a nest of their own. The fertilized queen therefore 

 insinuates herself into the nest of another species, perhaps kills the nest 

 queen, and becomes accepted in the host colony. The workers of her 

 own brood do no work in the nest, but raid other nests and bring home 

 immature stages. These on maturity become the foraging workers of 

 the colony and do not take part in the raids. Such colonies thus come 

 to include raiding individuals of one species, and ordinary workers of 

 another species. 



All ants do not live underground. There are, for example, the 

 famous army ants of the Tropics that live for the most part on the 

 surface. Though these ants are called army ants, they do not go 

 out to fight battles. Vast numbers of them together carry out foraging 

 raids on the territory around the nest. Almost every small ground- 

 living creature that cannot escape is captured, killed, and carried off 

 as food ; even young nestling birds may be attacked, and humans do 

 best to step lively. The biology of the army ants on Barro Colorado 



