Is Your Eye Color Real?

The eyes are often the first thing we see when we look at someone. And when you look at them up close, everyone’s eye color is a kaleidoscope of shapes and hues. How does eye color work? The answer involves some very cool physics, and probably isn’t what you were taught in school.

Season 7 Episode 10 Length 05:37 Premiere: 05/18/19

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Season 7 Episodes

Show Episodes

Show Clips & Previews

Could You Be a Chimera? (ASL)

S7 E31 Length 09:43 Premiere Date 06/21/19

This Could Change the Future of Space Travel

S7 E30 Length 11:30 Premiere Date 12/30/19

The Strange (Unexpected) Reason Ice is Slippery

S7 E29 Length 07:20 Premiere Date 12/17/19

Recycling Is Broken. Here’s How We Can Fix It.

S7 E28 Length 11:11 Premiere Date 12/10/19

I Tried Eating Bugs… Here's What I Learned

S7 E27 Length 14:55 Premiere Date 11/23/19

Evolution Fails in the Human Body

S7 E26 Length 11:53 Premiere Date 11/19/19

This Face Changes the Human Story

S7 E25 Length 13:11 Premiere Date 10/21/19

What If We Could See Nature In Infrared?

S7 E24 Length 08:51 Premiere Date 10/25/19

What Color Is A Banana?

S7 E23 Length 08:46 Premiere Date 11/09/19

What’s In a 20,000 Year-Old Cube of Ice?

S7 E22 Length 11:20 Premiere Date 10/07/19

The History of Money (From Barter To Bitcoin)

S7 E21 Length 09:36 Premiere Date 09/29/19

7 Scientific Urban Legends Debunked!

S7 E20 Length 11:24 Premiere Date 09/06/19

Why Don't Birds Lay Square Eggs?

S7 E19 Length 07:21 Premiere Date 08/19/19

How Blind People See With Sound

S7 E18 Length 16:07 Premiere Date 08/11/19

Why do Trees Talk to Each Other?

S7 E17 Length 05:27 Premiere Date 07/27/19

Why We Are Losing the Night Sky

S7 E16 Length 10:26 Premiere Date 07/14/19

Apollo’s Most Important Discovery: NASA’s Moon Rock Vault

S7 E15 Length 10:25 Premiere Date 07/09/19

Could You Be a Chimera?

S7 E14 Length 09:43 Premiere Date 06/21/19

Using Gene Editing To Repaint Butterfly Wings

S7 E13 Length 11:12 Premiere Date 06/18/19

1 MILLION Species Could Go Extinct… Here’s Why.

S7 E11 Length 05:55 Premiere Date 05/24/19