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Why Is Sex a Thing?

Why does sex exist? You might think the obvious answer is “reproduction” but there are plenty of organisms on Earth that don’t require sex to reproduce. And the more that scientists examined sex, the more they realized that it’s an expensive and inefficient way to get your genes to the next generation. The true purpose of sex is actually one of the longest-standing mysteries in biology.

Season 9 Episode 9 Length 12:31 Premiere: 07/30/21

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

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Season 9 Episodes

Show Episodes

Show Clips & Previews

The Unbelievable Science of How We Read

S9 E20 Length 16:14 Premiere Date 02/15/22

The Weird Way That Movies Trick Your Brain

S9 E19 Length 17:56 Premiere Date 02/01/22

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S9 E18 Length 16:20 Premiere Date 01/25/22

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S9 E17 Length 15:15 Premiere Date 01/06/22

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S9 E16 Length 14:29 Premiere Date 12/22/21

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S9 E15 Length 14:06 Premiere Date 11/23/21

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S9 E14 Length 09:21 Premiere Date 11/06/21

Sand Dunes Shouldn’t Exist (Here’s Why They Do)

S9 E13 Length 15:33 Premiere Date 10/20/21

I Can't Believe We're Making Another COVID Video

S9 E12 Length 16:20 Premiere Date 10/08/21

How the Zebra Really Got Its Stripes?

S9 E11 Length 13:13 Premiere Date 09/22/21

How Much Of You Is Alive?

S9 E10 Length 12:05 Premiere Date 09/07/21

Why Is Sex a Thing?

S9 E9 Length 12:31 Premiere Date 07/30/21

A Brief (Scientific) History of Butts

S9 E8 Length 12:27 Premiere Date 06/30/21

How Your Brain Makes Its Own Electricity

S9 E7 Length 18:46 Premiere Date 06/02/21

Why Are We Warm-Blooded?

S9 E6 Length 11:18 Premiere Date 05/04/21

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S9 E5 Length 12:38 Premiere Date 04/19/21

The Transcontinental Burrito Hypertunnel

S9 E4 Length 11:57 Premiere Date 04/01/21

What is Impossible in Evolution?

S9 E3 Length 19:29 Premiere Date 03/17/21

The Golden Ratio: Is It Myth or Math?

S9 E2 Length 22:36 Premiere Date 03/10/21

When Is Now?

S9 E1 Length 20:26 Premiere Date 02/15/21

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