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sleep
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References & Edit History Related Topics
Images & Videos
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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17 Questions About Health and Wellness Answered
Persian cat is sleeping
Why Do Cats Sleep So Much?
Irish Cobs in autumn pasture, horses
Why Do Horses Sleep Standing Up?
One day old human baby sleeping in a hospital. Newborn, dreaming, infant, napping sleep. reproductive system.
9 Fun Facts About Sleep
Discover
illustration of the walking titanosaurus, Patagotitan mayorum
Titanosaurs: 8 of the World's Biggest Dinosaurs
Ahura Mazda - relief of the Zoroastrian god Ahura Mazda at the ancient ruins of Persepolis in Iran. Also known as Ormazd Zoroastrianism,
Which Religion Is the Oldest?
Rural Irish landscape, Sligo, Ireland.
Why Is Ireland Two Countries?
Titanic infographic. The 30th anniversary of its discovery is September 1, 2015. SPOTLIGHT VERSION.
Timeline of the Titanic’s Final Hours
Fish. Lionfish. Lion-fish. Turkey fish. Fire-fish. Red lionfish. Pterois volitans. Venomous fin spines. Coral reefs. Underwater. Ocean. Red lionfish swims by seaweed.
10 of the World’s Most Dangerous Fish
New Zealand. Political/Physical map. Includes locator.
Where Is “Old Zealand”?
Small, white rat (genus Rattus) on a glass table. (rodent, laboratory, experiment)
Cruel and Unusual Punishments: 15 Types of Torture

sleep: Related Content

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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
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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?