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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.
Season 14 Episode 1 Length 17:13 Premiere: 03/10/26

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Season 14 Episodes

The New Kind of Heat Humans Can’t Handle
S14 E7 Length 21:23 Premiere Date 07/01/26

Scientists Finally Figured Out What Love Is For
S14 E6 Length 16:47 Premiere Date 06/11/26

We've never seen an atom. But we know what they look like.
S14 E5 Length 16:47 Premiere Date 05/28/26

Infinity isn’t a number. It's something much weirder.
S14 E4 Length 10:51 Premiere Date 05/14/26

Something Strange Happens When You Flatten the Earth…
S14 E3 Length 24:25 Premiere Date 04/21/26

You've Been Lied to About DNA Evidence
S14 E2 Length 22:37 Premiere Date 03/31/26

Traffic Lights Are So Much Weirder Than You Realize
S14 E1 Length 17:13 Premiere Date 03/10/26

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