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sleep
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Hear how scientists are studying the sleep-related brain activity of animals and migratory birds
Electroencephalogram
Why does jet lag happen?
Do we really swallow spiders in our sleep?
How biological clocks influence daily behavior
how poor sleep affects pain
Why sleep is so important
Why smartphones can disrupt sleep
adult polar bear and cub
For Students
adult polar bear and cub
sleep summary
Quizzes
greylag. Flock of Greylag geese during their winter migration at Bosque del Apache National Refugee, New Mexico. greylag goose (Anser anser)
Biology Bonanza
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Persian cat is sleeping
Why Do Cats Sleep So Much?
One day old human baby sleeping in a hospital. Newborn, dreaming, infant, napping sleep. reproductive system.
9 Fun Facts About Sleep
Irish Cobs in autumn pasture, horses
Why Do Horses Sleep Standing Up?
Discover
Berries and leaves of the bittersweet nightshade (Solanum dulcamara) plant. Poisonous plant
7 of the World’s Deadliest Plants
Shadow of a man holding large knife in his hand inside of some dark, spooky buiding
7 of History's Most Notorious Serial Killers
Drinking water is poured into a glass.
Water Fluoridation: Just the Facts
Aurochs. Bos primigenius. Skeleton. Extinct animal. Skeleton of an Aurochs, an extinct wild ox.
6 Animals We Ate Into Extinction
Internet http://www blue screen. Hompepage blog 2009, history and society, media news television, crowd opinion protest, In the News 2009, breaking news
Who Invented the Internet?
Gutzon Borglum. Presidents. Sculpture. National park. George Washington. Thomas Jefferson. Theodore Roosevelt. Abraham Lincoln. Mount Rushmore National Memorial, South Dakota.
9 Memorials and Monuments in the United States
Figure 13: A Maxim machine gun, belt-fed and water-cooled, operated by German infantrymen, World War I.
7 Deadliest Weapons in History

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News •

Max Richter's music put dozens of soldiers to sleep • May 16, 2025, 11:49 PM ET (CBC)

Photos and Videos

Electroencephalogram
adult polar bear and cub
Hear how scientists are studying the sleep-related brain activity of animals and migratory birds
Why does jet lag happen?
Do we really swallow spiders in our sleep?
How biological clocks influence daily behavior
how poor sleep affects pain
See All Videos and Images →

Related Topics and References

Topics
Dig Deeper: More Articles That Discuss This Topic

Key People

Édouard Claparède
Swiss educator and psychologist

Related Quizzes and Features

Quiz
greylag. Flock of Greylag geese during their winter migration at Bosque del Apache National Refugee, New Mexico. greylag goose (Anser anser)
Biology Bonanza
List
Hand washing. Healthcare worker washing hands in hospital sink under running water. contagious diseases wash hands, handwashing hygiene, virus, human health
17 Questions About Health and Wellness Answered
Demystified
Persian cat is sleeping
Why Do Cats Sleep So Much?
Irish Cobs in autumn pasture, horses
Why Do Horses Sleep Standing Up?