Aestivation Aestivation Aestivation or æstivation (from , summer, but also spelled estivation in American English) is a state of animal dormancy, similar to hibernation, characterized by inactivity and a lowered metabolic rate, that is entered in response to high temperatures and arid conditions. It takes place during times of heat and dryness, the hot dry season, which are often the summer months. Invertebrate and vertebrate animals are known to enter this state to avoid damage from high temperatures and the risk of desiccation. Both terrestrial and aquatic animals undergo aestivation. The fossil record suggests that aestivation may have evolved several hundred
Chionophile colder conditions arrive, animals go into a state of suspended animation called hibernation, when they go into a state of inactivity for long periods of time, which they do not come out of until more suitable conditions for them to survive in arrive. However, when animals live in an environment that is inhospitable for much of the year, then hibernation is not necessary. One of the few animals that does so are lemmings, which have a mass migration after they come out of dormancy. However, most animals living in the arctic would still be active, even during the most brutal