Dormancy

Dormancy is a state of reduced metabolic activity that many organisms adopt during periods of environmental stress.[1] The stress may be expected (e.g., winter and summer, two common times of dormancy) or unexpected (e.g., drought). Dormancy during winter and summer is called hibernation and aestivation, respectively.

## Contents

* 1 Hibernation
* 2 Aestivation
* 3 Non-biological uses
* 4 References

## Hibernation[edit]

As noted above, hibernation is a behavior of certain animals, particularly in cold climates, of entering dormancy as a means of coping with the vicissitudes of winter. While many animals will sleep more than usual during the winter, true hibernation involves dramatically reduced heartrates and body temperatures, generally over a single unbroken period of torpor.

Animals that hibernate include bears, the dormouse, the hedgehog, and many types of reptiles and amphibians.

Most birds migrate to avoid harsh seasonal conditions; the common poorwill, a type of nightjar, is the only bird known to hibernate. Historically, swallows were believed to hibernate at the bottom of ponds.

## Aestivation[edit]

As noted above, aestivation is a behavior of certain animals, typically in hot climates, involving a period of dormant behaviour to avoid the extremes of summer. It is a rather less common behaviour than hibernation. Animals that aestivate include certain types of crocodile and lungfishes.

## Non-biological uses[edit]

The words "dormancy" (noun) and "dormant" (adjective) are also used more generally to describe things that are not active. For example, a dormant volcano is one that is not erupting,[2] and the term "Dormant Commerce Clause" refers to situations in which Congress has not exercised its powers under the Commerce Clause.

## References[edit]

1. ↑ "dormancy." Encyclopædia Britannica Online
2. ↑ Definition of "dormant"