Directions: Read the following passages and choose the best answer.
Social parasitism involves one species relying on another to raise its young.Among vertebrates, the best known socal parasites are such birds as cuckcos and cowbirds; the female lays an egg in a nest belonging to another spacies and leaves it for the host to rear. The dulotic species of ants, however, are the supreme social parasites. Consider, for example, the unusual behavior of ants belonging to the Genus polyergus. All special of this ant have lost the ability to care for themselves. The workers do not forage for food .feed their brood or queen, or even dean their own nest. To compensate for these deficits. Polyergus has become specialized at obtaining workers from the related Formiaca. to ,Polyergus do these chores.
In a raid, several thousand Polyergus workers will travel up to 500 feet in search of a Formica nest, penetrate It,drive off the queen and tier. Workers, capture the pupal brood and transport it back to their nest The captuer brood is then reared by the resident is Formica workers untill the developing pupae emerge to add to the Formaci population, which maintains the mixed-species nest The Formica. workers forage for food and give it to colony. Members of both species . The also. remove wastes and excavate new chambers as the population increases.
The true extent of the Polyergus ants dependence on the Fomica becomes apparent when the worker population grows too large for the existing nest. Formica scouts locate a new nesting site, return to the mixed -species colony, and recruit additional Fomica nest mates. During a period that may last seven days, the Fomcica workers carry to the new nest all the Polyergus eggs, lanae, and pupae, every Polyergus egg,larvae, and pupae, every the Polyergus Queen.
of the approximately 8.000 species of ants in the world, all 5 species of Polyergus the and some 200 species in other genera have evolved some degree of parasite relationship with other ants.