Blood Types Are Weirder Than You Think

Across life on Earth, blood comes in blue, green, purple, even clear. But why? And what makes your blood different from mine? This is the strange world of blood—what it does, why it varies, and why we can’t live without it.

Season 13 Episode 8 Length 16:20 Premiere: 07/10/25

Recent Episodes

The Intelligence Test Where Ants Beat Humans

S13 E17 Length 14:52 Premiere Date 02/05/26

Everything I Thought I Knew About Flavor Was Wrong

S13 E16 Length 19:50 Premiere Date 01/15/26

The Scientific Lie That Damaged Generations of Men

S13 E15 Length 20:05 Premiere Date 12/18/25

Inside the Vault Where They Keep the Dinosaur Apocalypse

S13 E14 Length 22:36 Premiere Date 12/04/25

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S13 E12 Length 11:08 Premiere Date 10/23/25

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S13 E11 Length 36:47 Premiere Date 10/02/25

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Length 21:29 Premiere Date 09/16/21

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Length 17:08 Premiere Date 09/01/21

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Length 20:59 Premiere Date 08/18/21

These Death-Eating Scavengers Are Real Life-Savers

Length 29:33 Premiere Date 08/04/21

Elephant Moms Carry the Wisdom of Generations

Length 25:36 Premiere Date 07/21/21

Are Some Species More Important Than Others?

Length 25:47 Premiere Date 07/08/21

The Surprising Species That Everything Else Depends On

Length 25:47 Premiere Date 07/08/21

The Superb Owl!

Length 04:11 Premiere Date 02/02/17

The 12 Days of Evolution - Complete Series!

Length 17:43 Premiere Date 01/26/17

The Surprising Origin of Thanksgiving Foods

Length 05:09 Premiere Date 11/13/16

Do Animals Mourn Their Dead?

Length 04:17 Premiere Date 10/23/16

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