Do all animals sleep?

TitleDo all animals sleep?
Publication TypeJournal Article
Year of Publication2008
AuthorsSiegel JM
JournalTrends Neurosci
Date Published2008 Apr
KeywordsAnimals, Rats, Sleep, Sleep Deprivation

Some animals never exhibit a state that meets the behavioral definition of sleep. Others suspend or greatly reduce 'sleep' behavior for many weeks during the postpartum period or during seasonal migrations without any consequent 'sleep debt.' Rats die from one form of sleep deprivation, but sleep loss has not been shown to cause death in well-controlled studies in other vertebrate species. Some marine mammal species do not show evidence for REM sleep, and convincing evidence for this state in reptiles, fish and insects is lacking. The enormous variation in the nature of rest and sleep states across the animal kingdom and within the mammalian class has important implications for understanding the evolution and functions of sleep.

Alternate JournalTrends Neurosci.
PubMed ID18328577
Grant ListHL41370 / HL / NHLBI NIH HHS / United States
MH64109 / MH / NIMH NIH HHS / United States
NS14610 / NS / NINDS NIH HHS / United States