View full lesson: http://ed.ted.com/lessons/how-plants-tell-time-dasha-savage

Morning glories unfurl their petals like clockwork in the early morning. A closing white waterlily signals that it’s late afternoon. And moon flowers, as their name suggests, only bloom under the night sky. What gives plants this innate sense of time? Dasha Savage investigates how circadian rhythms act as an internal timekeeper for flora and fauna alike.

Lesson by Dasha Savage, animation by Avi Ofer.