# Are there any animals that do not sleep? **URL:** \ **Category:** Factual Questions\ **Created:** [March 23, 2008, 4:11pm UTC](https://boards.straightdope.com/t/are-there-any-animals-that-do-not-sleep/442440 "2008-03-23T16:11:02Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![doubled](https://avatars.discourse-cdn.com/v4/letter/d/51bf81/32.png) [@doubled](https://boards.straightdope.com/u/doubled)\ **Post date:** [March 23, 2008, 4:11pm UTC](https://boards.straightdope.com/t/are-there-any-animals-that-do-not-sleep/442440/1 "2008-03-23T16:11:02Z")
Is there any type of animal that does not need to sleep? Even a simple life form like an insect, maybe? ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [March 23, 2008, 5:17pm UTC](https://boards.straightdope.com/t/are-there-any-animals-that-do-not-sleep/442440/2 "2008-03-23T17:17:33Z")
As I understand there’s debate over whether sharks sleep or not, but no one knows for sure. Dolphins sleep one brain hemisphere at a time; so while they get sleep, as an individual they are never wholly asleep. ---
**Author:** ![ChrisBooth12](https://avatars.discourse-cdn.com/v4/letter/c/e95f7d/32.png) [@ChrisBooth12](https://boards.straightdope.com/u/ChrisBooth12)\ **Post date:** [March 23, 2008, 6:02pm UTC](https://boards.straightdope.com/t/are-there-any-animals-that-do-not-sleep/442440/3 "2008-03-23T18:02:55Z")
From what I understand insects do not sleep. ---
**Author:** ![Chez\_Guevara](https://avatars.discourse-cdn.com/v4/letter/c/aeb1de/32.png) [@Chez\_Guevara](https://boards.straightdope.com/u/Chez_Guevara)\ **Post date:** [March 23, 2008, 6:20pm UTC](https://boards.straightdope.com/t/are-there-any-animals-that-do-not-sleep/442440/4 "2008-03-23T18:20:44Z")
SD Staff Report: [Do Insects Sleep?](http://www.straightdope.com/mailbag/minsectsleep.html) (Short answer: Yes, but not the way we do.) ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [March 23, 2008, 7:01pm UTC](https://boards.straightdope.com/t/are-there-any-animals-that-do-not-sleep/442440/5 "2008-03-23T19:01:49Z")
Albatrosses, which need to fly continuously, as well as ducks, also sleep with one hemisphere at a time, so they are never entirely asleep. ---
**Author:** ![mks57](https://avatars.discourse-cdn.com/v4/letter/m/b9bd4f/32.png) [@mks57](https://boards.straightdope.com/u/mks57)\ **Post date:** [March 24, 2008, 6:00am UTC](https://boards.straightdope.com/t/are-there-any-animals-that-do-not-sleep/442440/6 "2008-03-24T06:00:37Z")
Sooty terns (wideawake birds) spend most of their lives in the air. When I was in the South Atlantic, I could go outside, late at night, and see large numbers of them flying in the breeze. They only seemed to land for nesting and breeding. > **[Sooty tern](https://en.wikipedia.org/wiki/Sooty_Terns)** > > 2-9, see text > Onychoprion fuscata (lapsus) > Sterna fuscata Linnaeus, 1766 > Sterna fuliginosa J.F. Gmelin, 1789 > Sterna fuscata fuscata Linnaeus, 1766 > Sterna fuscata nubilosa > and see text > The sooty tern (Onychoprion fuscatus) is a seabird in the family Laridae. It is a bird of the tropical oceans, returning to land only to breed on islands throughout the equatorial zone. ---
**Author:** ![Flander](https://avatars.discourse-cdn.com/v4/letter/f/8c91f0/32.png) [@Flander](https://boards.straightdope.com/u/Flander)\ **Post date:** [March 24, 2008, 1:30pm UTC](https://boards.straightdope.com/t/are-there-any-animals-that-do-not-sleep/442440/7 "2008-03-24T13:30:11Z")
Chuck Norris doesn’t sleep. He waits. d & r ETA - Haven’t we done this one before?