View full lesson: http://ed.ted.com/lessons/how-does-your-body-know-what-time-it-is-marco-a-sotomayor

Being able to sense time helps us do everything from waking and sleeping to knowing precisely when to catch a ball that’s hurtling towards us. And we owe all these abilities to an interconnected system of timekeepers in our brains. But how do they work? Marco A. Sotomayor details how human bodies naturally tell time.

Lesson by Marco A. Sotomayor, animation by TOGETHER.