Secret Lives of Ants

10. Con Artists of the Ant World: Parasites That Have Cracked the Ants’ Secret Code

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 parasites that have cracked the ants’ secret code Con Artists of the Ant World 10 To human eyes, it really is quite a sight to see slave ants faithfully serving their slavemasters, even though the master ant looks nothing like the slave. Ants do have eyes and can see the differences between one object and another. However, since ants rely so heavily on a chemically based language, some things happen frequently in the ant world that we humans who rely so heavily on our sense of sight might find hard to believe. Humans can see that uninvited guests such as beetles and caterpillars that ants willingly give food to do not belong to the ant colonies they exploit; it is, however, their ability to imitate the ants’ smells and behavior that cons the ants into giving them what they want. Rove Beetles, Masters of Disguise Rove beetles are the best-known of thousands of types of mites, moths, beetles, millipedes, crickets, and butterflies that live as the uninvited guests of ant colonies. When an ant nest is dug open, one can find rove beetle adults and larvae wandering around unmolested in the nursery, for example, or other heavily guarded areas of the nest. They receive food from the worker ants as if they were ant larvae, and they even feast upon the ants’ larvae right before the workers’ eyes. The worker ants go so far as to groom these con artist rove beetles as if they were their own larvae. How do the beetles pull off cracking the ants’ code, slipping through their security net and swaggering around inside the belly of the beast? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . c o n a r t i s t s o f t h e a n t w o r l d 83 The rove beetle larvae’s technique of begging for food from passing ants by tapping on them is so refined that they do this in exactly the same way that ant larvae do. As soon as the ant’s antennae feel the rove beetle larva’s body, the ant lifts up the upper part of the larva’s body and the larva feels around until it finds the ant’s face. The larva then lightly taps on the ant’s mouth, below the jaws, with its own mouth. The ant then feeds the larva by spitting up food into its mouth before carrying the larva to the nest. The rove beetles do not just give a password to get past the ant sentries; their trickery allows them to penetrate deep inside the enemy camp escorted by the very guards whose job is to keep them out. The rove beetle larvae are masters of disguise, with infiltration missions that are like something from Mission Impossible. Rove beetle adults can also imitate the way that worker ants beg each other for food. The rove beetle uses its antennae to tap passing worker ants to get their attention, and if an ant comes over, the beetle taps on the ant’s mouth with its front legs. The ant then spits up some food into its jaws for the rove beetle to slurp up. As if these mouth-to-mouth feedings were not enough pampering for the rove beetles, they even have glands that imitate the pheromones that ant larvae secrete to ask the worker ants to lick them clean. A rove beetle has secretory glands on both sides of its back that produce chemicals almost identical to the chemicals that the larvae are coated in so that the worker ants can identify them. The rove beetles’ false chemicals are so effective that when they are squeezed onto a piece of paper shaped like an ant larva, ants will pick up the paper “larvae” and carry it to the colony’s nursery. Highwaymen of the Ant World Not all rove beetles infiltrate the ants’ nests in order to cause them trouble. Instead, they fleece the ants of the food that they are carrying back to their nests. Some rove beetles, also known as highwayman beetles, trick the ants by imitating the way worker ants beg each other for food. These beetles, however, are not equipped with the deceptive glands that other species of rove beetles have, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . t h e c u l t u r e o f a n t s o c i e t y 84 so often the ants...