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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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15:15
We explore what we can actually do about pollution.
9:21
The biggest thing that has ever lived on Earth… is a tree? Hard to believe, but it’s true!
15:33
We travel to Great Sand Dunes National Park to climb the largest sand dunes in America.
12:05
There are parts of you that are living and dying at the same time. We find out how much.
12:27
This episode is about the science and evolutionary history of...butts.
