Metabolic Changes during
Estivation in the Common Earthworm Aporrectodea caliginosa.
Estivation (from the Latin word aestas, meaning summer) is a state of summer sleep'' or dormancy, resorted to by many animals during times of extremely high temperatures and drought.
Estivation is the summer version of hibernation; the newt takes a months' long sleep during the hot and dry months.
These data were collected during the early part of the dry season, when crabs begin a three-month period of
estivation (Sherman 1997).
He may also have been influenced by Francis Bacon whose Essays he is known to have read: in 'Of Building', first published in the third edition in 1625, Bacon writes that 'On the Under Story, towards the Garden, Let it be turned to a Grotta, or place of Shade, or
Estivation.' (7)
Rather than migrating to other bodies of water, the turtles remained buried in the basin after the pond was completely desiccated, possibly in a state of
estivation. Individuals continued to stay buried in th e dry basin and were located at the same sites two months later.
In addition to hibernating through the cold winter, many desert vertebrates (lizards, tortoises, ground squirrels, and susliks) also enter dormancy, or
estivation, during the hot dry summer period.
Aquatic turtles not only use upland habitats for nesting, but also for winter hibernation, summer
estivation, and movement from unsuitable aquatic habitats (Gibbons 1986, Buhlmann 1995).
These snails can survive during drought conditions for up to a year -- a period called "
estivation."
While the function of the coelacanth Aqp2-like channels remains unknown, the physiological role of the Aqp2-like channels in lungfishes is to promote antidiuresis during terrestrial
estivation in a manner entirely synonymous with the arginine-vasoticin-induced regulation of AQP2 channels in the kidneys of modern tetrapods (Konno et al., 2010).
Response to drought conditions depends largely on whether a species evolved in an arid or a humid environment; species with arid climate evolutionary histories have behavioral adaptations, such as
estivation, to cope with dry conditions, whereas those that did not evolve in an arid or xeric climate must emigrate (Gibbons et al., 1983; Christiansen and Bickham, 1989).
When temperatures become unbearable, they use clawed front feet to dig burrows and eventually enter a state known as
estivation, their metabolism slowed and systems all but shut down.
For example, during
estivation, the mouth of the shell of desert snails is closed by a thick epiphragm of calcified slime, which reduces water loss by evaporation so much that some desert snails can remain dormant for five years and revive when wetted.
Estivation studies of the convergent lady beetle in Arkansas.
This low wealth during the months of June, July and August can be explained by
estivation of snails for the purpose of protect themselves from desiccation due to high temperatures and intense sunshine during that season.
