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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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12:38
This could have devastating effects on our future.
11:57
We dug a classic doc that tells the story of the transcontinental burrito hypertunnel.
19:29
We explore all the questions that teach us what's possible in evolution!
14:49
We use lots and lots of mousetraps and ping-pong balls to show how this works.
16:43
Explore why we lie if we’re supposed to be the most socially developed species on Earth?
5:42
Glass is made of sand, which is a kind of rock. But glass is transparent. We explore why!
8:01
Do you know the true story of how his famous experiment changed the world?
15:14
Here’s the true story of one of the oldest human customs still in use today.