Ants Carrying Chips

Not all ants have the same kind of societies. The Australian bulldog ants are among the biggest and most basal of ants. Like virtually all ants they are eusocial, but their social behaviour is poorly developed compared to other species. Each individual hunts alone, using its large eyes instead of its chemical senses to find prey.
Some species (such as Tetramorium caespitum) attack and take over neighbouring ant colonies. Others are less expansionist but just as aggressive; they invade colonies to steal eggs or larvae, which they either eat or raise as workers/slaves. Extreme specialists among these slave-raiding ants, such as the Amazon ants, are incapable of feeding themselves and need captured workers to survive. Captured workers of the enslaved species Temnothorax have evolved a counter strategy, destroying just the female pupae of the slave-making Protomognathus americanus, but sparing the males (who don't take part in slave-raiding as adults).
Ants identify kin and nestmates through their scent, which comes from hydrocarbon-laced secretions that coat their exoskeletons. If an ant is separated from its original colony, it will eventually lose the colony scent. Any ant that enters a colony without a matching scent will be attacked.
Parasitic ant species enter the colonies of host ants and establish themselves as social parasites; species like Strumigenys xenos are entirely parasitic and do not have workers, but instead rely on the food gathered by their Strumigenys perplexa hosts. This form of parasitism is seen across many ant genera, but the parasitic ant is usually a species that is closely related to its host. A variety of methods are employed to enter the nest of the host ant. A parasitic queen can enter the host nest before the first brood has hatched, establishing herself prior to development of a colony scent. Other species use pheromones to confuse the host ants or to trick them into carrying the parasitic queen into the nest. Some simply fight their way into the nest.