Some species of ants keep slaves. Probably the best known for the practice is the large brownish-red Amazon ant. A slave raid starts with an assembly of the Amazon warriors outside their own nest. Then, almost ___(26)___ at a given signal, the group begins to march toward the colony ____(27)____. When the Amazons reach the nest of their intended victims, a fierce battle may take place. The Amazons fight on ____(28)____ they seize the pupae of the raided nest. They carry these back home. In time the pupae develop into adults and spend their lives working for the Amazons. The Amazons are completely dependent on their slaves ____(29)___ their sharp jaws, so well suited for fighting, are useless in taking care of larvae or for digging. Also, the masters become so lazy that, after a while, they lose their muscles, and they become too weak ___(30)___ to feed themselves. Finally, they become so unhealthy that they die.
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