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# Evolution: On the Run
- URL: https://www.cascadepbs.org/show/nova/episode/evolution-on-the-run-elrcak/
- Published: 2026-11-10T21:15:21.000Z
- Updated: 2026-11-11T13:30:16.000Z
- Description: How did running machines like the horse evolve from creatures that couldn't move on their own?
- Author: Cascade PBS Staff
- Tags: NOVA, Season 53, Episode 17, #ZZZ_Episode_34a84454-64b1-4752-a392-7fb9437f130d, #episode, #ZZZ_Show_8f1ff589-6222-4260-acbf-0523a6424abf, #geo-us, #v1.16

Billions of years ago, the twitch of the first muscle cells ignited a revolution of purposeful movement. Take a wild evolutionary ride from these early aquatic ancestors to highly-optimized runners like the horse, whose story is linked to our own.