What is estivation and how does it differ from hibernation?

The answer

Estivation (also spelled aestivation) is a state of dormancy similar to hibernation but triggered by extreme heat and drought rather than cold. The African lungfish can survive up to four years buried in dried mud, encased in a mucus cocoon, with its metabolic rate dropping to one-sixtieth of normal. The western spadefoot toad burrows underground and secretes a waterproof cocoon of shed skin to prevent dehydration, emerging only when it detects the vibrations of heavy rainfall. Some land snails estivate by sealing their shell opening with a layer of dried mucus called an epiphragm. While hibernation is characterized by dropping body temperature, estivation often involves maintaining elevated temperatures, and the physiological mechanisms for preventing organ damage during prolonged inactivity differ significantly.