Final answer:
The larvae of the African fly can survive in a dehydrated state, enter a dormant state when water is scarce, and rehydrate and grow into adult flies when water becomes available.
Step-by-step explanation:
The unique ability of the larvae of an African fly is that they can survive in a dehydrated state. These larvae typically inhabit puddles and when these puddles dry up, the larvae are capable of entering a dormant state. They can remain in this sleep-like state without any water for extended periods, with the provided example being as long as 17 years. When the environment is favorable again and water becomes available, the larvae are able to rehydrate, awaken, and continue their growth into adult flies.