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NOVA
Mysteries of Sleep
Season 47
Episode 4
From fruit flies to whales, virtually every animal sleeps. But why? Why do we need to spend nearly a third of our lives in such a defenseless state? Scientists are peering more deeply into the sleeping brain than ever before, discovering just how powerful sleep can be, playing a role in everything from memory retention and emotional regulation to removing waste from our brains.
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53:32
Discover how two revolutionary ancient inventions changed the course of humanity forever.
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53:27
Discover how Homo sapiens outlasted Neanderthals – and how they helped make us who we are today.
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53:25
Follow Homo sapiens as they venture out of Africa and spread farther than any other human species.
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53:32
Trace the remarkable origin story of Homo sapiens and the crucial moments that shaped our species.
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53:27
Forensic science is put to the test after the first-ever staged multi-vehicle pileup.
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53:29
A first-of-its-kind experiment aims to stage a multi-vehicle pileup to gain new data on car safety.
1:36:42
After centuries of pseudoscience, researchers examine the causes of racial health disparities.
53:41
Follow scientists in a quest to understand how complex forest ecosystems can help cool our planet.
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53:39
Explore key military technologies in the American colonies’ fight for freedom.
53:32
Follow the investigation into the deadly container ship collision that closed the Port of Baltimore.
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53:40
Archaeologists uncover new truths about Pompeii, a wealthy Roman playground with dark secrets.