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It's Okay to Be Smart
Traffic Lights Are So Much Weirder Than You Realize
Why are stop lights red? The common explanation about red light traveling farther through fog is actually wrong. The real story involves early railroads, deadly accidents, an exploding gas traffic light, forgotten inventors, and even the evolution of primate color vision. Here’s how history and biology accidentally created the nearly perfect traffic signal.
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16:47
If everything around us is made of atoms, why can’t we actually see them?
10:51
This video explores the bizarre mathematics that show how infinity is far stranger than a number.
24:25
How Gerardus Mercator later created a map that transformed navigation forever.
22:37
DNA solves crimes, but what happens when it sends innocent people to prison?
14:52
How thousands of tiny brains, obeying simple rules, solve problems no individual can understand.
19:50
Joe visits a flavor lab to uncover how our senses shape our taste.
22:36
How did the mass extinction of the dinosaurs play out, moment by moment?
12:37
Think traits like eye color or tongue-rolling are simple genetics? Think again.
11:08
Why is the Martian sky red by day… but blue at sunset?
