Some animals can survive extreme conditions that are beyond the limits of their normal metabolic activity. Adaptations to achieve this include dormancy and migration.
Aestivation is an adaptation for survival in high temperatures or drought conditions.
It is used as a method to stop desiccation (drying out) of the animal. Aestivation is common in invertebrates such as worms and snails as well as other animals like lungfish and crocodiles.
The lungfish can survive without water because it can breathe air and can hibernate for four years underground to stop desiccation.