Aestivation

Aestivation is characterized by inactivity and a lowered metabolic rate, that is entered in response to high temperatures and arid conditions.

Invertebrate and vertebrate animals are known to enter this state to avoid damage from high temperatures and the risk of desiccation.

A study done on Otala lactea, a snail native to parts of Europe and Northern Africa, shows that they can wake from their dormant state within ten minutes of being introduced to a wetter environment.

[2] Gastropoda: some air-breathing land snails, including species in the genera Helix, Cernuella, Theba, Helicella, Achatina and Otala, commonly aestivate during periods of heat.

To seal the opening to their shell to prevent water loss, pulmonate land snails secrete a membrane of dried mucus called an epiphragm.

In certain species, such as Helix pomatia, this barrier is reinforced with calcium carbonate, and thus it superficially resembles an operculum, except that it has a tiny hole to allow some oxygen exchange.

[7] Adult alfalfa weevils (Hypera postica) aestivate during the summer in the southeastern United States, during which their metabolism, respiration, and nervous systems show a dampening of activity.

Some amphibians (e.g. the cane toad and greater siren) aestivate during the hot dry season by moving underground where it is cooler and more humid.

[17] Animal physiologist Kathrin Dausmann of Philipps University of Marburg, Germany, and coworkers presented evidence in a 2004 edition of Nature that the Malagasy fat-tailed dwarf lemur hibernates or aestivates in a small tree hole for seven months of the year.