A high definition time-lapse of Oxalis triangularis (also known as the love plant or purple shamrock) going to "sleep". The leaves are light sensitive and fold away as the light levels drop towards the end of a day.
One image captured every 30 seconds for about 1.5 hours, played back at 25 frames per second; ~750x actual speed! The exposure time was progressively increased through the video so the drop in ambient light levels can't be seen.
![](https://i.ytimg.com/vi/VrZI5pDSifI/maxresdefault.jpg)